,illustration3 ,,first-,,class #e-;,,in4 ,,centre ,,lathe1 ,,with ,,traversing ,,mandrel ,,and ,,overhead ,,apparatus1 ,,by ,,james ,,munro1 ,,lambeth4 ,,the ,,lathe ,,its ,,uses2 ,,or1 ,,instruction ,,in ,,the ,,art ,,of ,,turning ,,wood ,,and ,,metal4 ,,including ,a ,,description ,,of ,,the ,,most ,,modern ,,appliances ,,for ,,the ,,ornamentation ,,of ,,plane ,,and ,,curved ,,surfaces4 ,with an ,appendix1 ,,in ,,which ,,is ,,described ,,an ,,entirely ,,novel ,,form ,,of ,,lathe ,,for ,,eccentric ,,and ,,rose ,,engine ,,turning2 ,a ,,lathe ,,and ,,planing ,,machine ,,combined2 ,and other ,valuable ,matter relating to the ,art4 ,,copiously ,,illustrated4 ,,new ,,york3 ,,john ,,wiley ,,son1 ,,publishers1 ,,no4 #b1 ,,clinton ,,place4 #ahfh4 ,,preface ,although the title of this work is sufficient to declare its contents1 a few prefatory remarks may not be superfluous as to its design and the manner in which that design has been carried out4 ,it has ever been to the writer a matter of surprise and regret1 that although the art of turning has been so long and so successfully pursued in this country1 both by artisans and amateurs1 no work has appeared in the ,english language treating upon the subject1 except one or two sketches and imperfect treatises4 ,some years since ,mr4 ,holtzapffel advertised a forthcoming series of seven volumes1 intended to supply this manifest deficiency in our scientific and mechanical literature1 and the subject would have been handled by him in a thoroughly exhaustive and masterly manner4 ,the untimely death of that gentleman occurred after the publication of the first three volumes1 which are indeed complete in themselves1 and of immeasurable value to the mechanic and amateur2 but which are unfortunately only introductory1 simple turning by hand-tools being the special subject of the proposed fourth volume4 ,the present proprietors of the firm of ,holtzapffel ,co4 having1 in their catalogue even up to the time of the most recent edition1 continued to advertise the seven volumes1 amateurs especially have anxiously hoped for the publication of some part at least of the remainder of the series4 ,that expectation is1 it is to be feared1 little likely to be rewarded2 and1 not until that fact had been ascertained with something bordering upon certainty1 did the author of the present work venture to take up the pen and endeavour to set forth the principles and practice of an art which1 like so many others1 he has found so absorbing and attractive1 and withal so delightful a source of recreation to mind and body4 ,several things1 however1 contributed to make the writer hesitate to undertake such a work4 ,in the first place he was aware that a number of possible readers would probably be more competent than himself for such a task1 especially those whose means might have enabled them to procure a large amount of the most modern and approved apparatus connected with the ,lathe1 and whose occupations might allow of more leisure for their extensive use than falls to the lot of the writer4 ,in the next place the risk of publication was such as he felt himself hardly justified in encountering4 ,just at this time1 however1 chance placed in his hand two or three numbers of the ,english ,mechanic1 in which some one else had begun1 but speedily resigned1 a series of papers ,on the ,lathe and its ,uses1 compiled from ,american journals4 ,the author of the present work at once put himself in communication with the editor and proprietor of the above periodical with a result now well known to the readers4 ,the following pages are not1 strictly speaking1 a mere reprint from the ,english ,mechanic4 ,the papers have been carefully revised and re-arranged2 some statements1 the correctness of which appeared doubtful1 modified or wholly withdrawn2 while1 in one or two instances1 whole chapters have been re-written1 and the suggestions and inventions relating to the ,lathe1 furnished by other correspondents1 embodied 7when they appeared of real value7 in the work4 ,but1 in addition1 a valuable ,appendix is now published1 containing matter of great importance1 contributed by one or two gentlemen1 who most kindly placed their papers at the service of the author4 ,foremost among them stands a paper on the angles of tools1 by ,dodsworth ,haydon1 ,esq41 of ,guildford4 ,a clever arrangement of ,lathe for ,rose ,engine ,work1 by the aid of the ,eccentric ,chuck without ,rosettes1 is also added from the pen of ,mr4 ,elias ,taylor1 of ,brighton2 and one or two matters1 which did not appear so fully treated as they deserved in the body of the work1 have been resumed and more fully discussed in the ,appendix4 ,the author gratefully acknowledges the suggestions of various correspondents1 amateurs and working men1 from whom1 as a rule1 he has not failed to obtain any required assistance4 ,that the work1 in its present form1 is entirely satisfactory or complete1 the writer cannot pretend2 that many errors have crept in is highly probable2 but1 if it is acknowledged to be the best work yet produced on the ,lathe1 and should prove in any degree serviceable to amateur or artisan in the pursuit of this most delightful art--aye1 if it should stir up some abler pen to write a better and more complete series1 it will afford real pleasure and lasting gratification to ,,the ,,author4 ,,contents ,,preface4 ,introduction4 ,chucks4 ,hand ,turning of ,wood4 ,hollowed ,work4 ,cutting ,screws4 ,hollowing ,out ,soft ,wood4 ,american ,scroll ,chuck4 ,metal ,turning by ,hand ,tools4 ,overhead ,apparatus4 ,self-acting and ,screw-cutting ,lathes4 ,wheel ,cutting in the ,lathe4 ,fret ,saws to ,mount upon the ,lathe ,bed4 ,turning ,spheres4 ,hoblyn's ,compound ,slide-,rest4 ,chucks with ,slides and ,compound ,movements4 ,turning ,ovals1 etc41 by ,means of a ,template4 ,eccentric ,chuck4 ,curiosities4 ,grooving and ,mortising ,small ,work4 ,ornamental ,turning4 ,the ,eccentric ,cutter ,frame4 ,segment ,engine4 ,holtzapffel's ,rose ,cutter ,frame4 ,universal ,cutter ,frame4 ,rose ,engine4 ,rectilineal ,chuck4 ,epicycloidal ,chuck4 ,the ,spiral ,chuck4 ,,appendix4 ,professor ,willis's ,tool ,holder for the ,slide ,rest4 ,munro's ,planing ,machine to be attached to the ,lathe1 and worked with the foot4 ,hicks' ,expanding ,mandrel4 ,turning ,spheres by means of ,templates4 ,plant's ,geometric ,chuck4 ,a ,paper on the ,principles which ,govern the ,formation and ,application of ,acute ,edges1 with special reference to ,fixed ,turning-tools1 contributed by ,mr4 ,dodsworth ,haydon4 ,detached-cutter ,holders4 ,new form of ,rose ,engine by ,e4 ,taylor4 ,oval ,turning and ,rose ,cutting with ,templates with my ,apparatus4 ,,the ,,lathe ,,and ,,its ,,uses4 ,the ,lathe has now for many years been steadily making its way from the workshops of our leading artisans to those of the amateur and lesser stars of the mechanical world4 ,this is but the natural result of the various additions and improvements which have been introduced into its construction from time to time4 ,the unworkmanlike and clumsy tool of olden days has long since been superseded by one of admirable finish and perfect aptitude for its designed uses2 and now that its construction is no longer dependent upon the skill of the workman alone1 but upon machinery moving with the precision of clockwork1 the fitting of the various parts is accomplished with the greatest ease and certainty4 ,the sale being thus extended1 the price has considerably diminished--the monopoly enjoyed by one or two makers no longer exists2 and there are few of a mechanical turn of mind who cannot now provide themselves with a lathe suited to their requirements4 ,nevertheless1 the adepts in the art of turning are by no means so numerous as might be expected1 and1 among amateurs especially1 it is rare to find work executed in first-rate style by simple hand tools requiring skill and practice in their use1 so that it not unfrequently happens that a workman who can turn out exquisite specimens of ivory carving and ornamental lathe work1 is but a fourth-rate hand with the gouge and chisel4 ,but however beautifully executed such ornamental work may be1 the credit is rather due to the tool than the workman1 and a well turned box with accurately fitting cover may bespeak more skill in handiwork than the above elaborately designed specimen4 ,moreover the one requires lathe fittings1 which are not always to be had unless the purse is well filled1 whereas the general mechanic 7amateur or professional7 can provide the tools needed for the other2 hence we propose first of all to give some practical hints on plain hand turning of wood and metal4 ,the ordinary form of foot lathe is well known and requires no special description1 it is represented in the frontispiece of this volume4 ,there are1 however1 certain points of detail in its construction1 to which it is necessary to direct the reader's attention4 ,first and foremost comes the mandrel1 of which there are several patterns1 according to the special purpose for which the lathe may be intended4 ,now of whatever form it may be made this is the essential part of the lathe1 and must run with the utmost truth in its bearings4 ,imperfection here will be imparted to all work executed upon it1 and accuracy in this part alone will make up for any slight defects that may occur in less important parts of the machine4 ,for ordinary work in wood alone or in brass the best form is represented in ,fig4 #a4 ,illustration3 ,,fig4 #a4 ,illustration3 ,,fig4 #c4 ,illustration3 ,,fig4 #b4 ,the part a1 b1 should be cylindrical1 with a feather let in to fit a slot in the pulley shown in ,fig4 #b4 ,this pulley1 whether of hard wood or metal1 is thus slipped on the mandrel as far as the collar d1 d1 and a nut e1 screwed up tightly at the back of it1 fixes it securely in its place1 from which it may be moved if requisite and replaced without fear of being out of truth4 ,this cannot be done if the mandrel is squared at a1 b1 and the pulley driven on with a hammer1 as commonly done by inferior workmen4 ,the part c1 is made conical1 to fit a hardened steel collar of similar shape4 ,the angle of this conical part is of some importance1 as if it is too small the mandrel is apt to jam and stick tight in its bearings4 #ce will be found to work well4 ,with regard to the length of this conical part1 opinions differ considerably1 but it must be remembered that friction is independent of the extent of the bearing surfaces and depends on the force with which they are pressed together 7in the present case it depends on the tension of the lathe cord and the weight of the material to be turned71 so that a tolerably wide margin may be allowed in this matter4 ,practically the question is decided by the thickness of the casting of the poppet head1 which is regulated by the required strength and size of the lathe4 ,the collar is sometimes of hardened steel1 sometimes of brass4 ,the latter would theoretically cause less friction than the former1 but practically nothing can beat a well finished collar of hard steel4 ,collars of this material made by the original ,holtzapffel two generations back are now as good as ever1 perhaps even better4 ,the centre1 which screws up against the left-hand end of the mandrel1 should be of the form shown in ,fig4 #c--;a plain cylinder with a screw cut at each end to receive clamping nuts4 ,the central part is rather larger than the screwed parts1 and passes truly through the poppet head4 ,this form is much better than a simple screw with points1 as the latter is not likely to keep the line of centres in being screwed up into its place4 ,it will be found of great convenience to have the screw on the nose of the mandrel 7and indeed all screws about the lathe7 of standard ,whit worth pitch1 as taps for the chucks are thus readily obtained1 and nuts and screws of the various sizes may be also procured to remedy breakages and losses4 ,upon this subject1 however1 we shall have occasion to treat more fully when we pass from the description of the lathe itself to the work that is to be accomplished by its aid4 ,the only form of back poppet that need be particularised is that made with cylinder and leading screw4 ,the simple pointed screw passing through the lathe head tapped to receive it1 not only requires no special description1 but it is only calculated for lathes of the commonest design1 as it is seldom that the line of centres is accurately maintained by the point at every part of the revolution of the screw4 ,moreover1 the latter soon works loose in the poppet1 and for anything like accurate work becomes speedily useless4 ,the cylinder and pushing screw is indeed far superior to the form just alluded to1 and where cheapness is an object it has its advantages over the first-named and best form4 ,it is represented in ,fig4 #d4 ,the cylindrical part is shown at ,b1 and may have at one end the usual point1 and at the other a small conical hole or hollow centre4 ,it may then be reversed in its bearings at pleasure1 or other cylinders with different shaped ends can be substituted1 as may be found convenient4 ,of course the pushing screw ,a is for the purpose of advancing the cylinder1 which is clamped by the small screw at ,c4 ,the cylinder and leading screw are shown in detail in ,fig4 #e1 which is the poppet head bored throughout to receive the spindle or cylinder ,a4 ,at the right hand this bore is enlarged to form a recess1 ,b1 to receive the head of the leading screw1 ,c4 ,this screw is generally made with a left-handed thread1 so as to withdraw the back centre when turned from right to left4 ,the spindle ,a1 ,a is bored1 and a left-handed female thread is cut from end to end--this however is turned off at the place destined to receive the movable point or centre1 and a hole slightly tapering is cut1 or if preferred a cylindrical hole is made and tapped for the same purpose4 ,the spindle has also a slot cut from end to end1 into which a screw enters from the poppet1 preventing the spindle from turning round while the internal screw is revolving by means of the small wheel and handle fixed to its right hand end4 ,the spindle is now put in its place1 the screw inserted and turned till the head or flange1 ,c1 rests in the recess before mentioned--a flat plate1 ,f1 is then attached to the back of the poppet by three or four screws1 the head of the leading screw passing through its centre2 the small wheel is then attached and the whole is complete4 ,illustration3 ,,fig4 #d4 ,illustration3 ,,fig4 #e4 ,it is evident that by turning the wheel the internal screw is put in revolution1 and as it is prevented by its flange from assuming any motion in the direction of its length1 the movable cylinder will instead be withdrawn or thrust forward4 ,this form of poppet is the best that can be adopted and is of general use in all first-class lathes4 ,in addition to the movable point g1 a flange similar to ,h should be fitted4 ,this will be found of great use when the lathe is used for drilling1 the piece of work resting against it1 while the pressure is regulated by the leading screw4 ,there are1 in addition to the flange and pointed centre1 other pieces of apparatus that can be substituted1 as occasion may require1 and these will be hereafter described in this series4 ,with regard to the common rest for hand turning a lengthened description is unnecessary4 ,the ,t or tee should for wood turning be of the form shown in ,fig4 #f at ,a4 ,it is often made as ,b1 which is a very inconvenient pattern1 as the cross piece on which the tool rests cannot be advanced sufficiently close to the work if the latter exceeds a diameter of two or three inches4 ,for metal turning the top of the rest should be flat1 and about one inch broad1 as the heel of the hook tools used for turning iron must be able to take a firm bearing upon its surface4 ,sometimes a plate of brass is riveted on the flat top1 as the tool takes a firmer hold on this metal1 and when the latter becomes defaced and channelled it can be renewed without the cost of a new casting in iron4 ,the turner should be provided with two or three tees for metal and for wood1--one may be long enough to have two legs and require two sockets1 as shown at ,c4 ,this is convenient in turning long pieces of wood1--a very short tee1 not more than an inch in length1 should also be provided1 and if one tee is specially kept with a very level and smooth edge1 it will be found of great advantage in chasing screws--indeed the latter work can hardly be managed at all if the top of the rest is damaged and uneven4 ,the next part requiring description is the boring collar1 without which even a hand turning lathe can hardly be considered complete4 ,this boring collar is intended so to support one end of the work1 instead of its being held by the back centre1 as to enable the workman to get at the end of it for the purpose of drilling it4 ,suppose for instance the work in hand is a tool handle1 and that it is so far finished as only to require the hole for the reception of the tang of the tool4 ,if this is bored by hand with a gimlet1 it is seldom that the hole will be truly in the axis of the piece1 but when this is done in the lathe by the help of the boring collar the bore will be truly central1 and the tool when in place will fall in the same line with the handle4 ,this will conduce to the correctness of the work in hand more than the amateur or other workman might suppose1 and a row of tools thus truly handled and in good condition generally bespeaks an efficient and careful artisan4 ,there are several plans for boring collar of nearly equal efficiency1 and we shall describe one or two of the most common1 and also one invented by the author1 and which1 if carefully made1 is of great service4 ,fig4 #g represents a poppet head1 ,b1 which is but half the height of the other poppets of the lathe--a side view of this is shown at ,b1 ,fig4 #h4 ,near the top of this poppet is a hole through which passes a bolt ,c1 by which and its nut the circular plate ,a can be securely clamped in any desired position1 as it revolves freely on the bolt as a centre pin4 ,this plate is bored with a series of conical holes1 which are so arranged that their respective centres will be in a line with the centres of the mandrel when any one of them is brought into a position corresponding with the line c1 c4 ,the hole thus brought into position for use 7having been selected according to the size of the work to be bored71 takes the place of the back centre2 the end of the work rests in the cone1 which is greased or soaped to reduce friction1 and the rest being fixed at the other side of the boring collar1 the drill can be readily used1 and the bore afterwards enlarged if necessary with any convenient tool4 ,this boring collar is generally made of iron1 but a substitute of hard wood will frequently serve the purpose1 and can be made by the amateur1 who may be unable to obtain one of more durable material4 ,if made of wood the best unguent will be soap or black lead1 such as is used for grates1 or a mixture of the two4 ,this black lead or plumbago 7it has no lead in its composition7 will always be found serviceable where wood works upon wood1 and also to give a smooth surface to wooden patterns for casting4 ,illustration3 ,,fig4 #f4 ,illustration3 ,,fig4 #g4 ,illustration3 ,,fig4 #h4 ,where cost is an object1 a simple substitute for the boring collar is frequently made by the ordinary workman by a piece of board one inch thick1 shaped like ,fig4 #i1 with a single hole of the size most generally required2 and the work is then fitted to the boring collar1 instead of the latter to the work4 ,in turning tool handles1 for instance1 where a few dozen are required all of the same size1 or nearly so1 a device of this kind1 which can be made in a few minutes1 is sufficiently effective4 ,this form has been modified in two ways1 and either will be found convenient4 ,in the first1 the conical hole is made of the largest size likely to be required1 a set of boxwood plugs are then turned to fit this hole and are themselves bored in a similar way to suit various sizes of work4 ,the form of these plugs is shown in ,fig4 #aj1 which is a side sectional view1 and at ,b1 where the same is shown in perspective4 ,two small screws or pins b1 c1 ,fig4 #aj1 fitting into the holes a1 a1 ,fig4 #i1 prevent these flange-shaped plugs from turning round in the board as the work revolves4 ,the pattern of ,a1 ,fig4 #i1 may be varied1 and is better made of hard wood1 and of a form which will afford a good bearing upon the lathe bed4 ,illustration3 ,,fig4 #i4 ,illustration3 ,,fig4 #aj4 ,the second modification is more difficult to make1 but equally effective4 ,it is shown complete in ,fig4 #aa4 ,this form1 arranged by the writer1 has many advantages over the two last-named1 and is very serviceable4 ,a is the poppet1 of the full height of the ordinary lathe heads1 or a couple of inches higher4 ,b1 the slide forming the support of the piece to be bored4 ,the form of the poppet without this attachment is shown in ,fig4 #ab4 ,if for nice work it should be made of metal and the face of it planed1 but for general purposes hard wood will suffice4 b1 b1 ,fig4 #aa1 are two pieces of brass forming a groove or guide in which a slide ,b1 with dovetailed edges is fitted to work4 ,this slide is bored1 like the ordinary collar1 with conical holes of different sizes1 and should be made of metal and planed on back and edges4 ,over each hole is a mark1 and this is to be brought to a similar mark on the face of the poppet4 ,the plate is then clamped in position by a screw at the back of the poppet4 ,one or more of such slides may be fitted at pleasure1 and in case of wear or damage these are the only parts requiring to be renewed4 ,illustration3 ,,fig4 #aa4 ,illustration3 ,,fig4 #ab4 ,it is a good plan to arrange a socket and tee of a rest as b1 c1 ,fig4 #ac1 at the back of this boring collar1 especially as the position of the tool will be always the same1 so that the rest may be a permanent part of the poppet4 ,there is sometimes a difficulty with the ordinary form of boring collar in advancing the rest ,t sufficiently near the work 7the foot of the poppet1 and that of the rest preventing it1 by coming in contact47 ,there is another modification of boring collar1 forming at the same time a guide for the drill1 which in slender work1 where the tool is long and fine1 becomes almost a matter of necessity4 ,illustration3 ,,fig4 #ac4 ,this consists in making such a guide cone as mentioned and shown in ,fig4 #aj1 ,b1 but with a continuation containing a smaller hole for the drill1 as ,fig4 #ad4 ,both this and the other shorter cones above-mentioned may be made to screw into the poppet ,a1 ,fig4 #i1 instead of being kept in place by the pins at a1 a1 of that figure4 ,in that case however the hole in the poppet must be cylindrical and only used as a support for the cones themselves4 ,in addition to the use of these boring collars already alluded to1 they serve for the purpose of turning up the points of screws like those of lathe centres4 ,these are first formed between centres with carrier chuck1 the back poppet is then removed and the extreme point fitted through one of the holes of the boring collar and the marks of the centre turned off4 ,illustration3 ,,fig4 #ad4 ,another useful adjunct to the lathe is the back rest for supporting long and slender articles1 which would otherwise bend under the pressure of the tool4 ,the ordinary and simplest form is shown in ,fig4 #ae1 and this is of general use with brush handle makers and others whose work is confined to a few sizes and shapes only4 ,a better form is shown in ,fig4 #af4 ,a support of wood or metal shaped like ,a is clamped to the lathe bed4 ,through the upper part the slide ,b passes and is wedged up so as to support the work--or the socket of a lathe rest may be arranged to take the upright part ,a1 which must then be rounded1 as shown at ,c4 ,illustration3 ,,fig4 #ae4 ,illustration3 ,,fig4 #af4 ,a modification of the latter1 communicated to the ,english ,mechanic1 is shown in ,fig4 #af;,a4 ,its construction and mode of application is sufficiently evident without a detailed description4 ,fig4 #af;,b is another form made in metal4 ,it consists of two similar plates with a triangular opening ,a1 through which the work is passed1 and which has an oval slot ,d1 by which the apparatus is secured to the short poppet of the boring collar4 ,between the two plates slides a third1 partly visible at ,c1 which can be clamped by a screw at ,b1 this screw also serving as a stud by which the plate may be moved4 ,the work is allowed to take up its own bearing in the triangular opening as it revolves in the lathe4 ,the clamping screw of the poppet is then secured1 and the centering thus made certain4 ,the plate ,c is then made to descend so as to touch the work1 and clamped in that position4 ,this is a very good central support for long slender articles4 ,illustration3 ,,fig4 #af;,a4 ,illustration3 ,,fig4 #af;,b4 ,there is a plan practised by ,german turners by which the back rest is in a measure superseded1 and which may be mentioned here4 ,it is simply the peculiar method of using the left hand4 ,this is placed on the piece to be turned so that the fingers partly encircle the work while the thumb rests in the hollow of the gouge1 or upon the end of the tool4 ,the fingers thus form a back rest and keep the work pressed against the cutting edge1 which is further steadied by the thumb4 ,as the tool traverses the work the left-hand accompanies it1 and with a little practice a ramrod or similar long and slender article may be readily and accurately turned4 ,this position is shown in ,fig4 #ag1 and though the novice will find it difficult to work thus1 it is well worth the trouble of mastering1 as the method once acquired will be found of very great service4 ,illustration3 ,,fig4 #ag4 ,we have now described more or less in detail the principal parts of the lathe as adapted for hand turning4 ,before we dismiss this part of the subject1 however1 it will be necessary to say a few words respecting the bed and lower fittings1 the flywheel1 treadle1 and their adjuncts4 ,beyond question the iron bed1 planed as it now is at a moderate price1 by machinery1 is the best that can be adopted1 especially if it is intended eventually to fit up the simple tool with slide rest and superior apparatus4 ,nevertheless1 the pocket must in this case also frequently decide the question of material4 ,if wood is preferred by necessity or otherwise1 it should be hard wood1 beech1 or ,spanish mahogany1 unless it is proposed to plate the surface with iron4 ,this latter plan costs little and1 besides stiffening the bed1 it prevents the wear and tear caused by the constant shifting of the back poppet and rest4 ,a flat strip of iron one inch or an inch and a half wide can be picked out from the stores of any village blacksmith straight and level as it came from the rolls of the manufacturer4 ,selecting a piece of the required length and breadth1 the eighth of an inch thick or rather more1 the purchaser will have holes drilled and countersunk at intervals of nine or ten inches1 to receive #c_/d-;inch screws4 ,these strips will have to be laid upon the top of the bed1 at its inner edges2 they need not be let in flush with the surface unless appearance is studied4 ,they must then be screwed down firmly1 and by means of a file worked by both hands up and down their length 7not across them7 a good surface may be readily obtained4 ,if the iron is let into the bed this filing will abrade the wood work1 which is the reason why we prefer screwing it on the surface4 ,this method produces a very excellent and durable lathe bed1 and it will be free from much of the tremor which is so disagreeable while working upon a lathe entirely of cast iron unless the bed of the latter and the standards are more substantial than is usual with small lathes4 ,the standards supporting the axle of the fly wheel and bed may in like manner be of wood or iron4 ,even when the bed is of iron these may be of hard wood1 although it is customary to make them of the same material as the bed4 ,if of beech1 oak1 or mahogany1 as in some of ,holtzapffel's best lathes with iron beds1 the tremor before alluded to will be considerably lessened4 ,iron is nevertheless very neat1 and is quite the fashion with the majority of makers1 but is too often faulty in respect of solidity4 ,the standards as a rule are too slight1 an elegant pattern being studied to the sacrifice of substance and weight1 ,the bed and stand of a lathe cannot be too strong and stiff4 ,respecting this matter of stiffness and solidity we seldom find it sufficiently considered1 and1 even with practical workmen1 a defect in this particular is more frequently acknowledged and put up with than remedied1 although the comfort of a steady lathe is beyond question1 to say nothing of its superiority when good workmanship is studied 7as it always should be74 ,the old ,french lathes made in the form of a thick table with four stout legs1 forming the bed and back-board1 are by no means to be despised as patterns2 and instead of the usual method of making but one standard at end of the bed1 there can be no question that two additional ones add considerably to the stability of the machine4 ,the fly wheel should be sufficiently heavy and have three speed grooves on the rim and two additional ones to produce a slow motion1 which is required for turning metal4 ,the latter may be worked with ease in this way when the article to be turned is small1 but if heavy work is likely to be encountered the back geared lathe1 to be hereafter described1 must be substituted1 and the slide rest will then also replace the hand tools4 ,the crank axle is generally supported by two centre screws1 the points being hardened1 and also the ends of the axles1 which are accordingly made of steel1 and the holes for the centre screws neatly drilled and countersunk4 ,this is however not the most perfect method1 and as we are speaking of better class lathes1 as well as those of more common and cheaper make1 we must by no means omit to speak of a very superior way of fitting the crank axle4 ,the latter must be turned at both ends1 the wheel bored and slipped on1 and keyed in its place4 ,two wheels of brass about two inches diameter1 must then take the place of the centre screws4 ,these are called friction wheels1 and they must be placed sufficiently near each other to support the end of the axle between them1 as shown in ,fig4 #ag;,b1 a and b4 ,a pair of these must be thus fitted to each standard1 and after the axle is placed in position a third may be placed above it to prevent the lathe cord from lifting the axle out of place by its tension4 ,the axle and friction wheels will thus work together with an exquisitely smooth rolling motion--there will be no tendency to thrust the lathe standards apart as must result from tightening the ordinary centre screws1 and the friction of the axle on its bearings will be reduced to a minimum4 ,any person acquainted with the use of the lathe may readily fit up these friction wheels1 and the time and trouble so expended will be amply repaid by the superior ease with which the lathe can be used4 ,we may say the same of the chain and eccentric1 which can replace with similar advantage the crank and hook in ordinary use4 ,illustration3 ,,fig4 #ag;,b4 ,illustration3 ,,fig4 #ah4 ,for the latter the following arrangements are necessary4 ,a is the eccentric keyed to the crank axle1 and may be either in the middle of the same or1 as in ,muir's patent lathes1 at one end outside the standard4 ,around it passes the endless flat chain ,b 7known as crank chain74 ,this also passes round a roller in the treadle shown at ,c4 ,this chain does not act as a mere link1 but when the lathe is in action it moves round and over the eccentric and treadle roller4 ,the motion of the whole is smooth and regular1 and1 what is almost as important1 noiseless4 ,in ,muir's and other lathes the crank chain is used without the eccentric1 being applied to the crank instead4 ,perhaps there is not much to choose between the two1 but no one who has studied the eccentric and observed its exquisitely gentle and smooth motion in an ordinary engine can have failed to be struck by these valuable qualities4 ,it must however be remembered that its throw is half that of a crank of the same eccentricity and the latter will have the advantage in power size for size4 ,in whatever position the lathe may be set up let the rise of the treadle be moderate4 ,it is exceedingly disagreeable to work at a lathe where the rise of the foot board is so great as to bring the knee into contact with the lathe bed1 a consummation not infrequent in country made ones4 ,this is only to be escaped by giving up a certain portion of power4 ,let ,a1 ,b1 ,fig4 #ai1 be the line of the treadle when at rest2 c1 the crank4 ,to gain power we should let part ,a1 ,e1 be longer than ,e1 ,b1 as in the sketch4 ,but let this arrangement be made1 and when the crank is at its highest point1 the line ,g1 ,b1 will show the position of the treadle and foot board4 ,hence this kind of leverage is not practicably available to any extent1 and the length taken from foot board to link may with advantage be even less than that from link to the axle on which the treadle works4 ,in lathes1 of all machine tools1 it is essential that the workman should be able to stand easily1 that the movements of the leg and body should not be communicated to the tool1 the play of the treadle and such items of detail being of more consequence than might at first sight appear1 and any method tending to diminish friction1 vibration1 and noise is well worth consideration in planning this machine4 ,illustration3 ,,fig4 #ai4 ,we may now suppose the reader the happy possessor of a well made foot lathe1 long or short in bed1 high or low in poppet1 according to his need1 but1 of whatever size1 carefully made and firmly fixed in a well-lighted place1 and if possible on the basement floor--an upstairs workshop is objectionable owing to the certain vibration of a boarded floor4 ,he will now require certain chucks and tools1 many of the former of which he will have to make for himself4 ,,chucks4 ,no lathe can be considered well fitted until it is supplied with a large number of chucks1 by which strange term are signified the various appliances for fixing to the mandrel the article to be turned4 ,when it is considered how varied are the forms which present themselves to the turner1 it may readily be conceived that much ingenuity has to be exercised in contriving methods for mounting his work in the lathe2 and when in addition to variety of form1 variety of size has to be taken into consideration1 it is plain that a large assortment of chucks is a necessary item in the workshop of the turner4 ,a vast number of these chucks are of necessity made of wood1 as required1 and such wooden ones are altered from time to time to suit different-sized work1 till they eventually become so completely used up as to be only fit for the fire4 ,in addition1 however1 to these1 there are certain chucks of metal 7chiefly brass or gun metal7 which should always be ordered with a lathe1 or fitted to it before any work 7even the making of wooden chucks7 can be satisfactorily accomplished4 ,the first of these1 is represented in ,fig4 #bj1 the part ,a1 screws to the mandrel2 while the work is attached to the taper screw ,b4 ,the use of this chuck is to hold short pieces or flat discs1 which allow of a hole in the centre and require to be turned on the face4 ,it is only used for wood-work4 ,this is the chuck to be selected when it is desired to make a wooden chuck4 ,a piece of sound wood being chosen of the requisite size1 and roughly rounded by the axe or chisel1 a hole is made in one face by a gimlet rather smaller than the tapering screw4 ,the piece is then firmly screwed to the latter1 the opposite end dressed with gouge and chisel1 and the rest being placed across the end1 a hand-drill for wood is brought to bear upon the piece4 ,the hole thus made in the centre is then enlarged by any convenient tool until its diameter is only a little less than that of the screw cut on the lathe mandrel4 ,an inside screw tool is then made use of to cut a thread of the same pitch as that of the mandrel1 or a tap of similar size and pitch screwed into it 7the former is the best but most difficult method to a novice71 the piece detached from the taper screw chuck1 which is removed1 and the wood attached to the nose of the mandrel on which it may now be accurately fitted and finished to the requisite form and hollowed out or otherwise1 as may be necessary4 ,numberless articles may be in a similar manner turned upon the above chuck such as the bottoms of candlesticks1 ring or other stands1 bread-platters1 small wheels1 and so forth2 it may therefore stand as number one of these adjuncts to the lathe4 ,illustration3 ,,fig #bj4 ,fig4 #ba is the face plate1 another most serviceable chuck of almost universal application in such work as surface-turning and boring1 and where a hole in the centre is inadmissible4 ,to this belong various dogs or cramps1 a few forms of which are shown at a1 b1 c1 d4 ,these hold the work firmly down to the surface of the plate1 being tightened from behind by screw nuts4 ,it will be seen that there are four slots and numbers of holes in the face plate1 some of the latter being tapped for screws4 ,these slots and holes may be increased in number1 and some of the latter may be square instead of round1 and the cramps may be of all shapes and sizes1 because sometimes it may be required to hold down a flat piece of brass the eighth of an inch thick only1 and the next job may be to hollow an irregular block of wood of three or four inches in thickness1 or it may be necessary to bore out the boss of a wheel1 or to turn the rim--all of which1 and a hundred others1 are cases in which the aid of the face plate will be in requisition4 ,illustration3 ,,fig4 #ba4 ,fig4 #bb is the chuck specially used for turning rods of metal4 ,it consists of two parts1 the body ,a1 which screws to the mandrel1 and the piece ,b1 which passes through a slot and is clamped by a small screw at one side c4 ,to these must be added the carrier which is of such forms as ,a#a1 ,b#a1 ,c#a4 ,above is shown a rod of metal to be turned with this chuck in position for use4 ,of this we shall have to speak again when we arrive at the subject of metal-turning4 ,there should be several sizes of carriers kept in stock1 from #a_/d;in4 in the largest part of the ring to #b;in4 or #c;in41 or even much larger for heavy work4 ,the amateur will1 however1 scarcely need these larger ones4 ,the usual method of making the wood-holding chuck for work that is to be also supported by the back centre1 is to have a socket cast like ,fig4 #bc1 ,c1 with a central hole to take the fork ,a1 which is held in place by a set screw4 ,this socket is useful for other purposes as it will hold short pieces of iron to be turned1 but the fork is far inferior for general work to the piece b2 this is made of iron1 and the end of the cross 7against which the wood to be turned comes7 is sharpened but must not be too sharp4 ,the end of the piece of wood has then two saw-cuts made at right angles to each other into which the sharpened edges of the cross fall1 ,fig4 #bc ,d1 and the whole will turn together without any chance of slipping4 ,it often happens1 when the ordinary fork is used1 that if the tool chances to hitch in the work1 the latter is either thrown quite out of the lathe1 or the centre of the fork retains its place1 while the other two points slip and score the work4 ,this can never happen with the form ,b1 which is the most reliable pattern that can be devised for work of this nature4 ,illustration3 ,,fig4 #bb4 ,illustration ,illustration3 ,,fig4 #bc4 ,fig4 #bd is to some extent self-centering4 ,a piece of wood hollowed out conically has three nails1 or three-square saw-files so placed within the cone as to present three sharp edges inwards4 ,any piece of wood1 if not too hard1 will1 if placed with one end in the chuck1 while the back centre is screwed against the other1 centre itself in some part of this cone1 and1 being at the same time held by the three sharp edges1 will necessarily revolve in the chuck4 ,there are many cases in which even in this rough form such a chuck will prove useful2 but if it were cast in metal and the three edges formed by slips of steel1 and the whole accurately turned1 it would be a very efficient and good self-centering chuck4 ,in its more common form it is largely used by the turners of mop and broom handles1 who work rapidly and cannot afford to waste time in chucking their work4 ,with the above1 the lathe1 if worked by steam or water power1 is not even stopped1--the screw of the back centre has a quick thread1 so that a single turn to or fro fixes or releases the work2 and thus1 one handle being finished1 another piece takes its place in the chuck1 is fixed by a half-turn of the back screw1 and being set in rapid motion is turned and completed by a practised hand in a couple of minutes or less4 ,illustration3 ,,fig4 #bd4 ,fig4 #be represents another useful chuck1 generally of boxwood1 called the barrel stave chuck4 ,it is turned conical1 the largest part being towards the mandrel2 it is then wholly or partially drilled through1 after which saw-cuts are made longitudinally1 as in the drawing4 ,these allow a certain degree of expansion when a piece of work is fitted into it1 and it is tightened round the latter by driving on a ring of iron or brass4 ,this ring is sometimes cut with a coarse thread inside1 and a similar thread being chased on the outside of the chuck1 it is screwed upon the cone instead of requiring to be driven by blows of a hammer4 ,one important use of this chuck is to re-mount in the lathe1 for ornamentation by the eccentric cutter or other apparatus1 any finished work that could not be readily chucked in any other manner1 or to hold rings requiring 7like curtain rings7 to be turned on the inside4 ,such articles will1 from the nature of this chuck1 be truly centred at once2 and their exterior parts will not be liable to injury1 as they would be by being driven into an ordinary chuck hollowed out to receive them4 ,illustration3 ,,fig4 #be4 ,another useful chuck for turning short pieces of metal such as bolts and binding screws1 and which is in a great measure self centering is made of cast iron1 and is usually called the dog-nose chuck1 represented in ,fig4 #bf4 ,this is made with movable jaw hinged1 as more plainly seen in ,b4 ,the screw clamps these jaws firmly together1 and any small piece of work is thus securely held4 ,the centering1 however1 is not accurate1 though sufficiently so for many purposes4 ,the die chuck 7,fig4 #bg7 is accurately self-centering1 and although somewhat expensive1 is a valuable addition to the lathe4 ,this chuck consists1 first of all1 of a socket for screw to fit the mandrel1 and round flat plate of brass cast in one piece1 as in ,fig4 #bh4 ,this must be carefully turned and faced in the lathe4 ,two pieces of iron or brass are then screwed to the face1 as ,b1 ,b1 #bh;,a1 leaving a space between1 the sides of which are to be truly parallel4 ,these pieces may either be chamfered to form ,v-pieces1 or may be rectangular on their inner edges2 at ,c1 ,c1 a part of each is cut away1 and the outer or back plate is also filed down to receive the small plates ,d1 ,d4 ,e shows a groove in which a screw lies1 half of which has a right and half a left handed thread2 this is shown in ,fig4 #bi4 ,it will be evident that if this screw is placed in the groove of the bottom plate1 and its ends pass through the pieces ,d1 ,d1 which are screwed to the plates1 it can revolve in its bearings1 but will have no endwise motion2 the collar ,f resting in a recess under the top plate ,d4 ,this screw passes through a projection in the back of the pair of dies1 which projection also goes into the same slot in the back plate in which the screw works when turned by the key 7,fig4 #bg1 ,b74 ,the above being nicely fitted1 the dies moving evenly but stiffly in their places1 the plain top is screwed on1 keeping all firmly together4 ,this plate has a long opening or slot 7,fig4 #bg71 through which the jaws of the dies and part of the screw are visible4 ,the ends of the screw should not project1 as any such projection is calculated to bring to grief the knuckles of the turner--a consideration worth attention in every form of chuck--the squared ends of the screw lie in a recess in the small plates1 as shown in the section of one of these plates 7,fig4 #bh,x74 ,into this recess the key fits over the screw end2 and by turning this the dies are simultaneously moved asunder1 or closer together so as to grasp centrally as in the jaws of a vice1 any small article1 such as a screw or short rod of metal placed between them1 ,a similarly contrived chuck is often used under the name of a universal chuck1 for holding pieces of large diameter1 and is very useful for taking pieces of ivory which have to be hollowed or otherwise worked1 as will hereafter be detailed4 ,in this case the jaws may be semicircular in form1 as ,fig4 #cj4 ,illustration3 ,,fig4 #bf4 ,illustration3 ,,fig4 #bg4 ,illustration3 ,,fig4 #bh4 ,illustration3 ,,fig4 #bh;,a4 ,illustration3 ,,fig4 #bi4 ,illustration3 ,,fig4 #cj4 ,it is however1 evident that these two chucks have a rather limited range4 ,the first can only be used for small work1 and the only case in which the latter can take firm hold all round the work is when the jaws are just so far apart as that they form portions of the circumference of one and the same circle4 ,practically they will hold the work tightly under an extended range of sizes1 and they are thus of great use to the turner4 ,the following is however more perfect in operation1 from the fact that it has four jaws instead of two which meet concentrically4 ,this may be made either with two long screws at right angles to each other1 with right and left-handed threads to each1 as in the die chucks1 or more simply and1 in some respects more satisfactorily1 with four distinct screws1 all of the same pitch1 and all with squared ends of equal size1 to allow of the same key being used to turn them4 ,it is possible to use such a chuck as an eccentric chuck if desired1 which is certainly a recommendation in its favour over those which work always concentrically4 ,the face of this chuck is shown in ,fig4 #ca4 ,the ends of the four screws have a bearing in the small centre plate b1 whilst the collars or flanges rest in a recess under the several plates c1 c4 ,the face of this chuck is graduated by each die1 so that it is easy to set the jaws concentrically or to place one or more eccentrically to take in work of other shape than round or square4 ,the jaws of this form of chuck are used for two purposes1 either to hold work inside them like a vice1 or externally4 ,a ring1 for instance1 requiring to be chased on the outside is slipped over the jaws1 which are then caused to recede from the centre so as to hold the work securely4 ,if the latter does not run truly1 one or more of the screws can be slackened1 and the opposite ones tightened1 or if the eccentricity appears to be in an intermediate part1 two adjacent screws will have to be thus slackened and the others tightened4 ,on the whole this is a most useful pattern of chuck4 ,illustration3 ,,fig4 #ca4 ,the following is a very excellent self-centering chuck now coming into extensive use4 ,it has been noticed in more than one periodical4 ,the description annexed is extracted from the pages of the ,english ,mechanic4 ,the chuck hereby illustrated seems to be a very convenient form1 easily adjusted and holding the drill securely4 ,it is also well adapted for holding wire to be threaded4 ,every piece of which it is composed is of cast steel well hardened4 ,it can be furnished with a shank to fit the hole for the centre1 screwed on the spindle1 or slipped on the centre4 ,no wrench is necessary1 the gripe of the fingers being sufficient to secure the shank of any drill4 ,the inventor claims that he has used a one-inch drill1 in tenacious wrought iron in one of them1 receiving a shank of only three-eighths of an inch diameter without using a wrench4 ,fig4 #ca;,a represents the shell of the chuck with milled bosses for the fingers4 ,the core1 ,b1 is threaded and receives a steel wire spring which is inserted into the rear of each jaw1 so that when relieved from pressure1 the jaws open automatically4 ,illustration3 ,,fig4 #ca;,a4 ,with this brief explanation1 the operation of the chuck can be easily comprehended4 ,these chucks are made of two sizes1 one with an opening of three-eighths of an inch1 and the other of three-sixteenths of an inch1 and they can be made of larger sizes4 ,patented by ,l4 ,h4 ,olmsted1 ,stamford1 ,connecticut1 ,united ,states ,america4 ,another chuck of self centering design1 has likewise appeared in the periodical above named1 into which it appears to have been copied from an ,american paper4 ,the accompanying engravings illustrate some improvements in the arrangement of chucks which have been recently patented in this country1 the inventors being ,messrs4 ,smith and ,haight1 both of ,new ,york1 ,u4,s4 ,the first part of the invention refers to an arrangement of adjustable chuck1 by means of which tools and other articles of different diameters may be held firmly in the jaws of the chuck4 ,fig4 #ca;,b is a longitudinal view of the chuck1 partly in section4 ,the spindle1 a1 is fitted so that it may be inserted tightly in the mandrel of the lathe4 ,on the front end of the spindle is a conical screw on which is fitted the cap1 b2 this part is formed with an opening at the front end1 having three longitudinal slots in it4 ,in each of these slots an adjustable jaw1 c1 is fitted1 the inner part of which is threaded with a female screw1 to fit the conical screw on the spindle1 a4 ,an outer casing d1 encloses the front part of the chuck1 and behind this is fitted a loose collar1 which is screwed into the casing d1 so as to connect the parts firmly together4 ,by turning the cap1 b1 with the casing1 d1 and collar1 in one direction1 the jaws1 c1 are moved forward and project out through the openings1 and they may thus be adjusted to grip a tool or other article of small diameter4 ,the opposite motion of the cap causes the jaws to recede1 and in this way they may be adjusted to grasp articles of different diameters4 ,illustration3 ,,fig4 #ca;,b4 ,another arrangement of the adjustable chuck is shown in ,fig4 #ca;,c1 which is a front view1 and ,fig4 #ca;,d1 a longitudinal section of the same4 ,a1 is the body of the chuck1 the front part of which is formed with a rim or flange1 in which are three radial recesses having fitted therein the sliding jaws1 ,b4 ,in the rear of each jaw is a bearing1 in which is fitted a pin carrying a small lever1 ,c1 the front end of which is rounded1 as shown in the section1 and enters a slot made in the jaw1 ,b2 so that when the levers are moved outwards they cause the jaws to contract or move towards the centre4 ,the back part of the body1 ,a1 of the chuck is threaded1 and on this part is fitted a collar1 ,d1 and in front of this is a sliding collar1 ,e1 which is connected to the collar1 ,d1 by means of a pin which enters a groove formed in the latter4 ,the sliding collar is prevented from turning round on the body1 ,a1 by means of a feather1 which works in a longitudinal groove formed in the inner circumference of the collar4 ,three inclined planes1 ,f1 are formed on the periphery of the collar1 ,e1 which extend to the backward ends of the levers1 ,c1 so that by moving the collar to and fro1 the jaws1 ,b1 are caused to contract or expand1 according to the size of the article to be grasped4 ,a short cylindrical block1 ,g1 made of a conical figure internally is fitted loosely within the chuck1 ,a1 and serves to centre the end of a drill or other short article1 but may be removed when it is desired to pass a rod or other article through the body of the chuck4 ,to provide for the easy turning of the collar1 ,d1 it is shown as fitted with a hand wheel1 ,h4 ,with this arrangement of the several parts1 the jaws of the chuck readily adapt themselves to drill or bit shanks as well as to articles of parallel form1 or of a tapered or irregular figure4 ,illustration3 ,,fig4 #ca;,c4 ,illustration3 ,,fig4 #ca;,d4 ,the chucks last named belong to the class of compound or mechanical tools2 and though their usefulness is beyond question1 they need not be considered absolutely necessary1 as the work which they are designed to facilitate can be and often is done without their aid4 ,indeed1 success in the art of turning by no means depends absolutely upon the possession of expensive apparatus1 and the amateur or mechanic will find the advantage of ransacking his own brain for the devising of divers makeshifts and off-hand contrivances--especially in this chuck-making department4 ,among the simple expedients the following will be found well worthy of adoption4 ,a1 ,fig4 #cb1 is a simple flange or flat brass plate with a boss behind1 similar to a small face plate1 and is to be turned up1 drilled1 and tapped to fit the mandrel4 ,if the latter has a diameter of #c_/d of an inch1 a few of these brass pieces should be cast from a set of wooden patterns ranging from two to three or four inches across the diameter of the plate1 and1 after having been fitted to the mandrel and turned1 four holes1 countersunk for wood screws1 should be made1 as shown in the sketch4 ,these are intended to do away with the necessity of boring out and tapping each individual wooden chuck4 ,they can be readily attached to any piece of wood by four screws1 and a few minutes will be sufficient to adapt the same to any required purpose4 ,a flat piece of board1 for instance1 itself too thin1 or of too soft substance to permit of its being attached to the mandrel in the ordinary way1 can thus be made into a temporary face plate1 or a ring cut out of it1 or any desired operation performed upon it4 ,indeed1 these socket pieces will be found serviceable on many occasions1 and will do away with the necessity of a large set of cup chucks4 ,illustration3 ,,fig4 #cb4 ,a few of the latter1 however1 are very useful and will cost but little4 ,the castings are sold by weight1 and the turner will experience no difficulty in fitting and finishing them for himself4 ,fig4 #cc is the form of these1 and needs no description4 ,the substance may be from #a_/h to #a_/d of an inch1 and need not be more1 as that thickness will stand any reasonable shock caused by driving a piece of wood into the chuck1 and it is always well not to overweight the mandrel with chucks of undue size or substance4 ,the addition of three to six screws to one or two sizes of the cup chuck extends its usefulness4 ,this form is represented in ,fig4 #cd1 ,a and ,b4 ,in this case1 the casting may be rather more substantial 7#a_/d to 8#c_/h of an inch in thickness74 ,the screws must be strictly radial1 pointing to the centre of the circle1 and their ends must be turned off or filed flat4 ,their heads may be squared to enable a key or pair of pincers to be applied1 or round with a hole through them4 ,it is better to make this kind of chuck with six screws--three in one plane1 and three again between these in another plane behind them4 ,in fitting a piece of work into the chuck1 it will not at first be found an easy matter to make it run truly4 ,the best way is to centre it as nearly as can be guessed1 by means of the three screws nearest to the open end of the chuck1 and then1 placing the latter on the mandrel1 set the lathe in slow motion and correct the eccentricity of the piece by means of the three inner screws4 ,even after this it is probable that a little alternate slackening and tightening of the different screws may be necessary2 but a little practice will quickly enable the turner to set a piece of work in the true axial line of the mandrel without much difficulty1 and the work will then be held very securely4 ,any short piece1 such as the ring of an eccentric to be bored truly inside1 may be held by the outer set of screws alone2 but if such a piece of work as a small cylinder is to be bored1 the six screws must be brought into action4 ,here let the hint given when speaking of projecting screws1 be repeated1 ,beware of the knuckles1 which are peculiarly liable to be damaged in making use of these chucks4 ,the shirt sleeve or coat1 moreover1 does not always enjoy perfect immunity from similar danger1 and both should be kept out of harm's way1 not for their own sake only1 but because the arm may be brought into violent contact with the rest if the sleeve should get entangled 7the momentum of the flywheel being great1 and therefore not to be checked entirely at any given moment74 ,a single rap of the above nature is not a delightful even if salutary lesson to the novice4 ,illustration3 ,,fig4 #cc4 ,illustration3 ,,fig4 #cd4 ,to hold rings and washers a tapering mandrel1 ,fig4 #ce1 is used2 and of these it is necessary to keep a few different sizes to suit different diameters4 ,these may be made of iron or brass if for permanent use1 but box or other hard wood is a ready substitute1 and may be turned down for smaller work when the surface gets spoiled by use4 ,the expanding mandrel1 ,hicks' patent1 which will be treated of hereafter1 is a convenient substitute for the simple conical form here spoken of2 and in manufactories where large numbers of mandrels have to be kept of various sizes1 a great saving of time1 money1 and labour is effected by their use4 ,for amateurs and artisans in a smaller way of business the simpler form is generally sufficient4 ,a slight modification is here appended1 by which the common form may sometimes be made more efficient in the holding a ring tightly while undergoing the operation of turning1 and this can be made applicable to metal mandrels1 though specially intended for wooden ones4 ,fig4 #cf4 ,illustration3 ,,fig4 #ce4 ,illustration3 ,,fig4 #cf4 ,the mandrel having been turned conical 7,n4,b41 the angle of the cone must be small1 so that the size will diminish very gradually from the largest end71 the wood is divided by a fine saw1 just as the chuck already described with the outside rings was sawn into segments1 a conical hole having been first made at the smallest end1 as shown in the section b1 b4 ,into this a short cone of larger angle is to be fitted1 against the end of which the point of the back centre will press1 tending to drive it into the mandrel1 which will thus be made to expand4 ,the ring to be turned will prevent the mandrel from splitting by the wedge-like action of the plug1 unless the said ring is of light substance1 in which case this form must not be used4 ,the work will1 by the above method1 be securely and centrally held and not liable to slip towards the small end of the chuck4 ,in the ,fig4 #cf1 a groove1 c1 c1 is shown at the bottom of the saw-cuts4 ,this should also be made round the boxwood spring chucks with rings1 as it gives more freedom of expansion to the segments4 ,with such a groove and the chuck itself completely hollowed out1 the pressure of a strong india-rubber ring will be sufficient to hold work whilst being polished3 and this will1 when the latter is delicate1 be even superior to the screwed rings1 as the pressure will be more gentle and equable4 ,india-rubber rings for this purpose must not be thin and flat1 like those used for bundles of papers or letters1 but made of round material1 the thickness of a quill or even larger4 ,they may be had of all sizes at an india-rubber warehouse in ,holborn1 at the bottom of the hill on the left hand side going eastward1 and not far from ,negretti and ,zambra's shop4 ,the writer is not acquainted with the name of the proprietor4 ,having had occasion to speak of tapping chucks of metal to fit the mandrel1 it will be as well to speak here of the requisite tools for effecting this4 ,in the case of iron chucks it is not likely1 as a general rule1 that the amateur or workman will obtain access to a screw-cutting lathe1 and to cut an internal thread by hand with the chasing tool is hardly feasible1 though readily accomplished in the case of brass chucks4 ,when1 therefore1 a lathe is purchased1 a set of taps of the diameter and pitch of the screw on the mandrel should be provided4 ,of these there must be three--an entering taper tap1 an intermediate one rather less tapering1 and a plug tap1 which is cylindrical4 ,and here we must enter a caution4 ,do not let the tapering taps be too long4 ,for instance1 let it be required to tap the boss of a face plate in which the hole cannot be drilled through the plate4 ,it is first bored out to the size of the bottom of the mandrel threads1 or rather less4 ,tap number one must then be screwed into it2 but if this is too long1 so that it cannot enter to the end of the threads cut upon it1 the second tap will be too large and will not enter properly1 but will most likely start a new thread for itself and spoil the first4 ,fig4 #cg1 a1 b1 c1 shows the form required2 d1 the form to be avoided1 except in cases where1 as in the cup chucks1 a hole can be made quite through the article1 so that the tapering tap can be worked to the line x1 y1 or nearly so4 ,the long tap1 gradually tapering as it does from end to end1 is of course the easiest to use1 and for nuts and such like is far the best2 the conical tap of larger angle requires more power1 but in the case named it is a matter of necessity to use it2 and1 if preferred1 a set of four taps instead of three will remedy any difficulty4 ,the novice must take great care to place the tap perpendicular to the face of the chuck1 or the shoulder will not fit close to that on the mandrel4 ,if much difficulty is experienced1 such an arrangement as ,fig4 #ch may be of service4 ,a represents the standard of an upright drill-post1 of which ,b is the bench1 ,c the screw by which to depress the drill and keep it to the cut4 ,for the latter1 and brace by which it is worked1 substitute the tap1 and place a spanner or wrench round the head of it4 ,in the centre mark1 which is generally left from the turning1 place screw point c4 ,by means of a plumb line or square1 ,d1 test the perpendicularity of the tap2 and as the latter penetrates1 keep it to its work by the screw ,c2 oil the tap freely1 and the chuck will be easily and accurately cut with the required thread4 ,some kind of clamp will of course be required to secure the chuck to ,b1 while it is being tapped4 ,illustration3 ,,fig4 #cg4 ,illustration3 ,,fig4 #ch4 ,the upright drill should always have a place in the workshop4 ,it is much easier to drill with it than in the lathe1 and the mandrel will thus be saved considerably4 ,the latter should never be used except for light work4 ,a variety of drilling apparatus will hereafter be described in this series1 so that we need not now write more upon this part of our subject4 ,somewhat akin to the chuck described as the cup chuck with six screws1 is a chuck mentioned in an old ,french work1#a the purpose of which is to turn up a cylinder1 with a point at the end1 so as to insure the axial line being kept4 ,in the ordinary course1 the cylinder would be turned up with the point and carrier1 or driver1 chuck already described2 the conical point would be then turned down as far as possible1 and the mark of the back centre afterwards turned off by means of the boring collar4 ,it is by help of a miniature lathe and boring collar in one piece that the pivots of the balance of a watch are finished4 ,in both cases the work may be well done by the same process4 ,the chuck now to be described requires no boring collar1 but at the same time it does not seem to be well suited for any but light work2 in which latter case however it would be advantageous1 and must therefore have a place in our present paper4 ,the body of the chuck is shown in section1 in ,fig4 #ci4 ,a is the socket with screw to fit on the mandrel of the lathe4 ,it will be seen that the chuck itself is hollowed out cylindrically1 and in this cylindrical cavity slides a plug1 c1 bored conically1 which can be fixed by a thumb-screw1 h1 traversing a slot in the body of the chuck4 ,this cone is destined to receive one end of the cylinder to be pointed1 which will1 according to its diameter1 centre itself in some part of the conical hole in the plug4 ,the latter is made movable1 so as to be adapted to the length of the article to be turned4 ,at the outer end of the chuck is a groove dovetailed to receive a slide1 shown clearly in the cross section ,b4 ,the slide must be of sufficient substance to allow a clamping screw1 f1 to be tapped into it at one end1 which screw must be long enough to reach when fully advanced nearly to the apex of the triangular opening seen in the slide4 ,the action of the whole contrivance is as follows3--,the cylinder to be pointed is placed in the conical cavity of the plug--the latter slid to or fro till the point to be turned projects a short distance beyond the mouth of the chuck through the triangular opening in the front slide2 when it is fixed by a turn of the screw1 f1 which forms the third point of resistance1 the sides of the triangular opening forming the other two4 ,as the point or apex of the triangle is always in the diameter of the cylindrical chuck1 it will only be necessary to move the slide itself in order to bring the axis of the cylinder to be turned in a line with that of the mandrel4 ,as soon as this is accomplished so that the piece runs truly1 the screw1 g1 is turned1 and the slide fixed in position4 ,a good deal of ingenuity is displayed by the inventor of this chuck1 a description of which was published twenty years ago1 and there are very many cases in which it will be called into requisition by the mechanic4 ,with a little care1 moreover1 the amateur might make one for himself--the body of brass or gun metal1 the plug and sliding part of iron or steel4 #a ,manuel de ,tourneur par ,h4 ,bergeron4 ,illustration3 ,,fig4 #ci4 ,amongst the various devices connected with the lathe1 many of which1 even as makeshifts1 are valuable to the turner1 is one not generally known for keeping up the tension of the lathe cord in whatever groove of the fly wheel or pulley it may be placed4 ,the plan is not more ingenious than practical1 and the writer is acquainted with one workman1 a gasfitter by trade1 who has had it in constant use for many years4 ,directly over the mandrel pulley is another of larger diameter1 in which are two grooves of equal depth1 fig4 #dj4 ,this upper pulley is suspended on a movable arm1 ,d1 which is pivoted at ,e1 and kept up by an india-rubber spring1 ,f1 or1 as in the original plan 7before these rubber cumulators were known71 by a cord passing over a pulley1 and having a heavy weight attached1 as shown by the dotted lines4 ,in the fig4 ,a represents the fly wheel1 ,b the mandrel1 ,c the upper pulley4 ,the lathe cord is very long1 and passes upwards from ,a1 over the upper pulley in groove #a1 down again and round the mandrel1 a second time over groove #b of the upper pulley and down to the fly wheel4 ,the tension of the cord is thus always the same1 and is regulated by the spring or weight4 ,if the cord is slipped to a smaller part of the lathe pulley1 the slack is instantaneously taken up by the descent of the weight1 and rising of the arm ,d1 which in like manner yields to allow the cord to be slipped to the larger groove of the mandrel pulley4 ,illustration3 ,,fig4 #dj4 ,there are many other useful contrivances for chucking work in the lathe1 a few of which will be noticed on a future page4 ,the main thing to be attended to is the holding securely as well as centrally the object to be turned4 ,if this is attained1 the precise form of chuck is of little importance1 and it matters not whether it be made of metal or wood4 ,the latter has indeed1 in some respects1 an advantage resulting from its elasticity and the ease with which its form is modified4 ,,hand ,,turning ,,of ,,wood4 ,we have now described the simple foot-lathe and chucks adapted for hand turning1 but of the latter a great number may be provided1 and will1 in fact1 accumulate as the turner proceeds to work upon objects of varied form and size4 ,no chuck once made should be thrown away until it has become so reduced1 from repeated alterations1 as to be no longer serviceable4 ,and now1 before we commence actual turning1 it will be well to offer a few concluding remarks upon the selection of a lathe4 ,it will be evident from our previous remarks and illustrations that there is room for great diversity in the size and quality of this machine1 and it is astonishing what excellent work is often turned out by an experienced hand from a lathe of the worst description4 ,the simple pole-lathe1 which is so out of date that we did not deem it worthy of notice in this series1 with its reciprocating motion1 like the little tool of the watchmaker1 has1 before now1 supplied the cabinet maker with first-class work1 and not many years since we ourselves stood before just such a clumsy tool1 taking first lessons in the art4 ,our next step was to a lathe with wooden poppets1 and flywheel of the same material1 a mandrel made by a country blacksmith1 which scarcely did even him credit2 the value of the whole1 with stand and beechen bed complete1 was #b sterling1 and sufficiently dear at that price4 ,now1 we do not recommend such a tool1 and in the present day a much better may be had at that price1 but1 notwithstanding its evident defects1 very tolerable work may be produced from it4 ,we state this to deter the reader from a very common fault--namely1 the purchase of an expensive tool and elaborate fittings when the purse is shallow1 and the skill shallower still4 ,in fact1 any amount may be spent in lathes1 and in fitting up a workshop1 but to gain real pleasure and satisfaction from the pursuit of the mechanical arts1 the outlay should not be more than the probable result in work fairly warrants4 ,a hundred pounds is often expended in the purchase of a lathe1 and a hundred shillings would more than purchase the work done by it4 ,we speak from our own experience in this matter1 and believe our advice proportionately valuable2 and we well know the satisfaction that ensues when good work has been produced in spite of the defects in the appliances at command4 ,if the means do not admit of the purchase of a good lathe necessity must decide the question1 and an inferior one must take its place in the workshop4 ,nevertheless1 we would rather counsel a certain amount of delay1 and economy and hoarding1 that a good foundation may be laid and a lathe purchased of such average excellence that future additions may convert it into a really serviceable tool4 ,it would be invidious and perhaps rather unfair in this little work to send the reader to any particular lathe-maker4 ,there are several good and two or three first-class ones in ,london1 and if prices range high1 the work is at any rate of undeniable excellence4 ,there are also many cheaper firms than those alluded to1 where the work is rather of rough-and-ready style2 all depends on what class of work the would-be purchaser proposes to engage in1 whether he intends to confine himself to plain hand-turning in wood1 to the construction of steam engine1 and other models of machinery in metal1 or to the more beautiful finished work in hard wood and ivory1 which develop the full power of the machine itself1 and the skill of the accomplished turner4 ,in the former cases1 a very plain and inexpensive lathe will suffice4 ,in the latter1 it is absolutely necessary to purchase one of the best construction1 at a tolerably high figure4 ,the best advice to those of slender means1 and who1 therefore1 vastly predominate1 is to sacrifice all else to the mandrel and collar4 ,the latter may be bought at from twenty to thirty shillings1 ready for mounting in detached wooden headstocks1 and will be far superior to any that an ordinary smith can produce4 ,in this case1 the two poppets that carry the mandrel and centre screw should be connected together by a block of wood between them1 which latter may be rounded off and shaped to something near the form of a cast-iron headstock4 ,the only care necessary in mounting such a mandrel1 will be to keep the axial line parallel to the lathe-bed1 and directly over the centre of the latter4 ,whether the mandrel is thus a separate purchase1 as may happen from necessity1 or obtained as part of the lathe1 and fitted in a cast-iron headstock1 it should certainly be hardened1 and also the collar1 if of steel4 ,both will take a higher polish for this process1 and will run easier in consequence4 ,the cost of such a mandrel is rather greater1 because many warp or split in the process1 and have to be thrown aside2 and the labour of grinding mandrel and collar to an exact fit1 is considerably increased4 ,the gain1 however1 is greater than the loss to the purchaser1 and the extra outlay must not1 therefore1 be grudged4 ,it is very annoying to find a conical mandrel worn down by the collar after a twelvemonths' work2 for a collar is thus formed on the conical part1 so that it cannot be tightened up by the back screw4 ,the first tool to be noticed is the gouge1 the form of which is a longitudinal section of a tube1 and is shown in ,fig4 #da4 ,of this tool not less than three sizes should be selected1 of the respective diameters of one inch1 half-inch1 and a quarter or three-eighths4 ,when purchased1 they require grinding1 the bevel being too short4 ,it is essential that this tool and the turning chisel have a long bevel1 so that the cutting edge should be a very acute angle4 7,fig4 #da1 not like #db47 ,it is impossible to do good work with the latter form of tool which is1 nevertheless1 of frequent occurrence in the workshops of amateurs4 ,both gouge and chisel must be sharpened on an oilstone 7,arkansas or ,turkey will be found the best7 to a keen edge1 and no pains must be spared in preserving the tools in this condition4 ,three sizes of chisel to match the gouges should be selected4 ,the latter tool is not made like that intended for carpenter's use1 with the edge at right angles to the sides1 but is sloped like ,fig4 #dc1 so as to present an obtuse angle ,a1 and an acute one ,b1 and the cutting edge is central1 the bevel being alike on both sides1 so that the tool may be turned over1 and used with either of the flat sides upwards4 ,the handles of gouges and chisels should be much longer than those used by carpenters1 and nicely rounded and shaped in the lathe4 ,the most difficult thing to turn being a cylinder of soft wood2 a description of the method of effecting this will be the best means of initiating the novice in the art of turning4 ,in all the most perfect work by practised hands1 there is a sharpness of edges and roundness of mouldings1 that are exceedingly agreeable to the eye1 and bespeak at once keenness in the tool with which the work has been done1 and steadiness in the hand of the operator4 ,the novice must aim at similar perfection1 and to this end he must determine to avoid the use of sand-paper1 and trust to his management of exceedingly keen tools to put a workmanlike finish to his work4 ,to commence with the proposed cylinder4 ,let a piece of sound beech be selected for the first essay1 as being less difficult to manage than deal1 the grain of the latter tearing up in long shreds under the action of the tool4 ,the first thing to be done1 after sawing off the necessary quantity of sufficient diameter for the proposed work1 is to round it off roughly by means of the hatchet and draw-knife1 or spoke-shave4 ,the next thing is to mount it in the lathe4 ,for this purpose the prong chuck1 or1 better still1 that represented as an improvement on the latter1 and shown in ,fig4 #bc;,b1 must be screwed on the mandrel1 and the work made secure by the aid of the back poppet centre4 ,care should be taken that the piece runs truly between the points of support1 and that it revolves steadily without shake4 ,there is no real necessity for using the compasses1 or other contrivance for finding the exact centre at each end1 as sometimes recommended1 neither1 indeed1 is it always possible thus to find the axial line4 ,it is easy to fix it at first lightly in its place1 and ascertain by a turn or two of the mandrel1 how nearly it runs as it ought to do4 ,if it seems tolerably true1 a turn of the back centre fixes it securely1 if not1 it can be shifted in any direction at pleasure4 ,the tyro ought1 however1 to be warned that he is likely to be deceived in the size of the rough piece1 and that he may very probably think it of sufficient diameter for the proposed work when in reality it is too small4 ,practice1 or the use of the callipers1 which are bow-legged compasses for measuring the diameters of work1 will soon settle the question4 ,the piece being properly fixed in the lathe1 the latter is to be set in motion by means of the treadle1 the rest having been first fixed as near as possible without touching the piece1 and the ,t clamped parallel to it4 ,if the tyro wishes to become a proficient1 no pains must be spared to acquire the knack of working the treadle without moving the body to-and-fro4 ,he must learn1 therefore1 to stand firmly on one leg1 and after the wheel has been put in motion1 he must let it and the treadle have its own way4 ,he will thus soon feel when the crank has passed the dead point at the highest point of revolution1 and the proper moment to bear down with the foot4 ,it is not necessary to describe the precise movement1 as a few trials will teach the method much better than any written description4 ,at first it is hard work1 and constant change of leg from the right to the left1 and back again1 will have to be resorted to to diminish the fatigue4 ,practice will1 however1 remove all difficulties1 and allow the whole undivided attention to be given to the management of the tool4 ,illustration3 ,,fig4 #da4 ,illustration3 ,,fig4 #db4 ,illustration3 ,,fig4 #dc4 ,the gouge must be held down firmly on the rest with the hollow side upwards1 and the bevel of the edge forming a tangent to the work1 ,fig4 #dd4 ,in this position it will cut freely and smoothly1 and the edge will be preserved4 ,if held horizontally1 as in ,fig4 #de1 it is evident that the fine edge of the tool will be immediately destroyed by the rapid blows it will receive as the rough wood revolves in contact with it4 ,its tendency in the latter position will be to scrape1 instead of cutting1 and the fibres of the wood will thus be torn out in threads1 and the surface of the work be roughened4 ,the gouge1 then1 being placed in the former tangential position1 the right hand grasping the handle1 the left the blade1 as in ,fig4 #df1 the tool is to be slowly slid along the rest1 and a series of light shavings1 more or less continuous1 will be removed from end to end of the piece4 ,let the workman bear in mind that the tool is to take a firm bearing on the rest1 and that it must not move to-and-fro with the inequalities of the piece to be turned4 ,it is not necessary to remove large chips unless the turner has acquired from practice perfect command over the tools1 and for the adept this chapter is not written4 ,after the most prominent inequalities have been removed1 the side of the gouge will come into use instead of the extreme end1 and with this the work may be rapidly reduced to its intended size1 always allowing1 however1 for the final cut with the chisel4 ,before the latter is taken up1 the piece of work is to be rendered as level and true as can be done by the aid of the gouge alone2 indeed1 if the latter is of tolerable size1 and skilfully used1 a finish can be put upon the work by it almost equal to that which the chisel can produce and if the work in hand were a moulded pattern1 with hollows and raised work1 great part would have to depend on the gouge alone4 ,in the present case the chisel must be used1 and the method is as follows3 ,take a hold with both hands1 as directed for the management of the gouge1 but instead of the flat part lying evenly on the rest1 the tool must be partly raised from it1 so that only the lower edge takes a firm bearing4 ,by this means the upper angle of the cutting edge 7generally the most acute7 is kept clear of the wood1 and the latter is cut away only by means of the middle and lower part of the edge1 as shown in ,fig4 #dg4 ,if placed as in ,fig4 #dh1 the acute angle1 a1 is sure to catch and stick into the work1 spoiling in two seconds all that has been done4 ,the chisel can be used with either of its flat sides upwards1 and moved along the rest from right to left1 or from left to right1 or turned upside down1 as ,fig4 #di1 so that the acute angle is downwards4 ,these positions are shown in the ,figs4 #dg to #ea4 ,the only care necessary is to keep the upper point clear1 allow the chisel to rest as flatly on the wood as the above precaution will permit1 and to take as fine and continuous shavings as possible4 ,the chisel will be found to draw itself along in some degree as the cut proceeds1 and when this action is felt1 it is doing its work properly--still1 it is a difficult thing to use a chisel well1 and the tyro will fail many times and oft before he will succeed4 ,illustration3 ,,fig4 #dd4 ,illustration3 ,,fig4 #de4 ,illustration3 ,,fig4 #df4 ,illustration3 ,,fig4 #dg4 ,illustration3 ,,fig4 #dh4 ,illustration3 ,,fig4 #di4 ,illustration3 ,,fig4 #ej4 ,illustration3 ,,fig4 #ea4 ,the chances are that this initiatory lesson will result in anything but a correct cylinder--the surface will not be true like a ruler1 but if tried by a straight edge it will be seen to be wavy4 ,tested by the callipers1 ,fig4 #eb1 one part will be larger than another1 even if the extreme portions be tolerably true to the proposed gauge4 ,now1 the best turner on earth found just these difficulties1 and nothing but perseverance and resolute determination will overcome them4 ,never mind spoiling the first piece of work1 give up making it of a determined size1 but do not give up making it a true cylinder4 ,keep the callipers at work1 and gently level the prominent parts 7you must work down to the size of the deepest hollow1 for you cannot fill up such valleys like a railway engineer2 you must throw down the adjacent hills instead71 proceed gently1 little by little2 make the tool obey you1 show it 7as ,ruskin speaks of pencil and brush7 that you will not yield to its caprices and henceforward it will be your most obedient servant4 ,having done the best you can with the surface of your cylinder1 proceed to square up the ends1 and mind the angle at this part is a right angle1 square and sharp1 not rounded off4 ,now this again requires care and a knowledge of the proper method4 ,you will work chiefly with the lower corner of the chisel1 and we shall best describe the management of the tool by supposing the cylinder an inch too long1 and that the extra piece is to be removed4 ,now there are three positions in which the chisel can be placed to bring its lower corner in contact with the cylinder4 ,first1 with the blade perpendicular to the work2 secondly1 with the blade inclined to the left1 ,fig4 #ec1 as if to round off the end of the piece2 thirdly1 inclined to the right1 ,fig4 #ed4 ,held perpendicularly it will cut a fine line1 but penetrate slightly2 alternately in the other positions it will remove a ,v-shaped piece1 and thus the cutting off is to be begun4 ,one side of the cutting1 however1 has to be perpendicular1 the other may be as sloping as convenient4 ,now1 it is to be remembered in cutting the upright side1 which is the end of the roller1 the chisel is to incline rather to the right1 for this reason1--if it incline to the left a momentary inattention will cause it to take the path a1 b1 ,fig4 #ee1 the tendency being to cut a spiral track towards the left4 ,the experiment may be made by gently resting the edge thus inclined on any part of the roller1 when it will describe a spiral at once4 ,to the right1 then1 the chisel must slightly incline1 and it will cut off a thin curling shaving like ,fig4 #ef1 leaving the end of the piece quite smooth and shining4 ,when the piece is nearly cut off1 great care and lightness of hand must be used1 as the central portion will have become weak and ready to break off before the work is finished4 ,when it will no longer bear the chisel1 take it out of the lathe1 break it off1 and neatly finish with the sharp chisel the central portion1 and your first lesson is learnt4 ,there is certainly very little of interest in turning an imperfect cylinder1 for it is useless when done1 but the alphabet of the art1 though not amusing1 must be first thoroughly mastered1 and the rest will follow in due course4 ,if1 however1 the work seem unreasonably dull and stupid1 the cylinder may be converted into a tool handle1 which will be at any rate a useful article1 besides affording practice4 ,no special directions are needed in addition to the above1 except in respect to the ferrule4 ,this is to be cut off a piece of brass tubing or an old gun barrel1 or it may be had at the tool shops ready cut to any size4 ,begin by turning down the place for this ferrule1 taking care not to cut it too small or the ferrule will drop off4 ,take the piece out of the lathe1 and with a mallet hammer on the ferrule4 ,return it again1 taking care to centre it in the old marks1 and finish the handle4 ,the brass or iron may be polished with a file for this first attempt4 ,illustration3 ,,fig4 #eb4 ,illustration3 ,,fig4 #ec4 ,illustration3 ,,fig4 #ed4 ,illustration3 ,,fig4 #ee4 ,illustration3 ,,fig4 #ef4 ,,hollowed ,,work4 ,it is now necessary to speak of hollowing out wood for the purpose of making boxes1 cup chucks1 c41 and the latter1 which may be made in any quantity1 and of all sizes1 will afford excellent practice in this part of the turner's art4 ,the majority of work of this kind is done rather by scraping or fretting out than by cutting2 side tools of the forms of ,figs4 #ea and #ef being used for the purpose4 ,these however1 are specially adapted for ivory and hard woods1 the grain of which1 being very compact and close1 is not torn out in shreds by the action of such tools1 as would be the case with softer woods4 ,where the latter material is used in quantity1 as in the manufacture of wooden bowls1 hook tools1 like ,fig4 #eg1 are made use of1 which cut on their upper edges4 ,these are exceedingly difficult to use1 though the practised hands of those brought up to the art1 make them cut with a surprising ease and rapidity--fairly surrounding the lathe with a ceaseless cloud of fine shavings removed in the progress of the work4 ,the difficulty experienced in the use of these tools is not confined to the novice1 for the majority of turners accustomed to hard wood often cut a sorry figure in the manipulation of softer material with the aid of the tools in question4 ,the hard and soft wood turners form1 in point of fact1 two distinct branches of the trade4 ,we have in part anticipated this section1 by speaking of the making a wooden chuck when describing the use of the metal chuck with taper screw4 ,we shall1 therefore1 proceed to describe the best method of turning a plain wooden box with cover1 but not screwed2 the latter being reserved for more extended notice hereafter4 ,the best material to work upon is sound ,turkey boxwood1 and care must be taken that it is quite dry and well seasoned1 or1 after it is worked up with1 it may be1 great care and trouble1 the box will split1 or the cover become so loose as to fall off1 either fatality being sufficiently vexatious4 ,we may mention1 in passing1 that hard woods of all descriptions may be had in large or small quantities of ,messrs4 ,fauntleroy#b and ,co41 #aaj1 ,bunhill-row1 ,finsbury1 or of ,jacques and ,sons1 ,covent-garden4 ,most of the lathe-makers also supply it1 especially ,holtzapffel and ,co41 of ,charing-cross1 but the first-named is a large dealer1 wholesale and retail1 and his charges are moderate4 #b ,now ,messrs4 ,mundy and ,berrie4 ,illustration3 ,,fig4 #ea1 #eb1 #ec1 #ed1 #ee1 #ef1 #eg4 ,supposing a selection made of size proportionate to that of the intended box1 including cover and a tolerable margin for waste and accidents1 proceed as before to rough it down between two centres and thus to reduce it to a cylindrical form--there is1 however1 no occasion to use the chisel at present1 as we only need a rough cylinder4 ,remove this from the lathe1 and if you have no brass cup chuck into which you can fit it1 proceed to make one out of a piece of beech1 ash or1 if you have plenty1 boxwood4 ,do not hurry the work1 but cut the chuck out neatly1 screw and fit it1 as previously directed1 on the nose of the mandrel4 ,we shall suppose it as yet merely a short neat cylindrical block1 quite solid4 ,place the rest with the tee across the end of the piece of wood1 the top edge a little below the centre 7by the thickness of the blade of the tool74 ,for the latter select one of the three following--either will answer well--#eh1 #ei1 #fj4 ,with one or the other drill a hole in the centre1 keeping the tool quite horizontal across the rest4 ,enlarge this hole by a left side tool1 working from the centre of the piece towards the outside1 not taking the whole depth at once1 but a quarter or half an inch at a time4 ,you must hollow it out about one inch1 and see how nicely you can fit the hollow to the size of the piece you are going to turn4 ,you will1 of course1 have squared up one or both ends of the latter1 which must now be driven tightly into the hollow chuck4 ,if you squared the ends of the cylinder correctly and left also the bottom of your chuck level and true1 you will be gratified by seeing the piece run evenly at once4 ,illustration3 ,,fig4 #eh1 #ei1 #fj4 ,fig4 #fa shows a section of the chuck with the piece to be turned fitted inside it4 ,now take the gouge and chisel and reduce the piece to a plain cylinder1 and take special care to square up the outer end4 ,this may be done by the aid of a carpenter's chisel held across the rest1 like the side-tool4 ,if the end is much out of truth you had better use first the round-ended tool1 ,fig4 #fj1 but if you have worked carefully from the commencement this will be unnecessary4 ,to ascertain the correctness of this part1 apply a small steel square like ,fig4 #fb1 the blade of which slides through the brass part and is clamped by a small screw at the side4 ,we show the method of applying this tool to gauge depth1 test right angles1 c41 in ,figs4 #fc and #fd4 ,it is a most convenient and necessary instrument1 and should be at once provided4 ,having thus ascertained that the end of your cylinder is at right angles with the side1 take the point tool1 ,fig4 #eh1 or the acute corner of your chisel1 and1 setting the lathe in motion1 mark off the intended depth of the cover1 as ,d1 ,c1 ,fig4 #fa4 7,observe1 it is the cover and not the box that first demands attention47 ,now proceed to hollow out the cover as you hollowed out the chuck1 but with greater care4 ,you must allow in the thickness of the top rather more material than you will eventually require1 the thickness of the sides1 also1 may be a trifle in excess1 but take the utmost care to make the inside rectangular1 that is1 the line f1 g1 perpendicular to g1 ,d4 ,upon the correctness of this the fit of the cover will depend4 ,this being done and tested as to truth with the square1 as before1 you may cut off the cover with a parting tool1 ,fig4 #fe4 ,this tool is thin1 with a cutting edge at the end1 and is held edgewise upon the rest4 ,the blade is made rather thicker near the end1 so that as the tool penetrates the work it may not bind1 but allow the small chips made by it to escape freely4 ,the rest must be removed from its former position and placed parallel to the side of the piece1 and the tee at such a height that the latter may1 when the tool is held horizontally1 point to the axis of the work4 ,the tool should be occasionally withdrawn1 and the point1 instead of being kept precisely in one position1 may be slightly raised and lowered from time to time1 describing a small arc4 ,it will soon be ascertained in what position it cuts most easily4 ,there are different sizes of parting tool1 some very thin in the blade1 for ivory and precious woods1 some thicker1 for box and less valuable stuff1 some with a notched end1 forming two points1 for soft woods1 the action of all being similar to a saw tooth1 or1 in the last1 to two adjacent saw teeth set out to clear themselves in working4 ,care must be taken that the thin blades do not bend and twist while cutting1 especially after the cut has become deep4 ,to avoid this do not hurry the work1 but take a little at a time1 and be careful to keep the tool with its sides perpendicular to the rest4 ,with these precautions the cover will soon be cut off neatly4 ,if care is not taken to allow for the necessary thickness of the cover1 the turner will be mortified by finding that instead of the latter1 he has merely cut off a ring1 and he will have to expiate his want of judgment by beginning a new cover and making a shallower box4 ,we name this to put him on his guard4 ,supposing the above work satisfactorily accomplished--the top of the cover1 however1 being 7as will probably be the case7 either convex or concave1 requiring a little touching up and finishing1 it will be necessary to turn down on the solid bit of wood left in the chuck the part ,a1 ,b 7,fig4 #ff71 on which the cover will eventually rest4 ,on no account1 however1 must this be now turned small enough1 it must be left so large as not quite to enter the cover1 because if it is now nicely fitted1 and the box subsequently hollowed out1 the cover is sure to be too slack1 the wood shrinking in the process of hollowing out4 ,this shrinking may be accounted for by supposing the rings of woody fibre1 the result of yearly growth1 naturally elastic1 with a tendency to contract1 each one1 like a series of india-rubber bands1 embracing that within it4 ,the central ones being removed by the tool1 permit the outer ones to contract1 their particles approaching nearer to each other and the structure becoming more dense4 ,this tendency causes those radial cracks so often seen in the ends of pieces of wood sawn from the trunk or limbs of the tree4 ,the outer parts becoming drier than the inner1 and prevented by the latter from shrinking1 necessarily split1 hence1 when it can be done1 the centre of such pieces is bored out1 while the wood is yet full of sap1 and the rest is thereby preserved4 ,where this cannot be done the ends may be covered with glue or resin2 or paper may be glued on1 to prevent access of air1 and thus the drying of the outer portion may be so retarded as only to keep pace with that nearer the centre4 ,the concentric rings thus shrink equally1 and no radial splitting takes place4 ,illustration3 ,,fig4 #fa1 #fb1 #fc1 #fd4 ,illustration3 ,,fig4 #fe1 #fh1 #ff4 ,we will now return from this explanatory digression to the work in hand4 ,having cut down the flange for the cover to nearly the required size1 proceed to hollow out the box4 ,work carefully1 so that the sides shall be smooth and perpendicular to the bottom1 and the latter plane and neat4 ,take care1 as with the cover1 to leave the necessary thickness of bottom1 allowing for the cut of the parting tool1 and1 if possible1 half an inch or more beyond it4 ,now finish that part on which the cover is to rest4 ,take great care1 as before1 to secure right angles1 and cut away the wood little by little1 trying on the cover from time to time1 until at last it will just go smoothly and stiffly into its place4 ,it must fit rather tightly1 but take especial care not to force it on1 or you will split and spoil it4 ,we shall here introduce to the notice of the reader another form of callipers useful in such work as the above1 and in many cases absolutely necessary4 ,they are called in-and-out callipers1 and are made as shown in ,fig4 #fg4 ,these are so arranged that whatever interval exists between a and b1 exists also between c and d4 ,if1 therefore1 the inside of a box cover 7or similar article7 is measured by the latter1 the other end of the instrument will show the exact size to be given to the part ,a1 ,b1 ,fig4 #ff4 ,the convenience of such an arrangement for an infinity of cases will be apparent on an inspection of the figure4 ,illustration3 ,,fig4 #fg4 ,illustration3 ,,fig4 #fi1 #gj4 ,the cover of the box must now be put on1 the lathe set in motion1 and the outside1 and also the top of the cover1 carefully turned and finished4 ,if the box is to be cylindrical1 care should be taken that it is truly so1 and that the angle formed by the junction of the top and sides is sharp4 ,if sand-paper is used to finish the work1 the edges will be rounded and the workmanlike appearance spoiled4 ,if1 therefore1 the article is made of box or other hard close-grained wood1 this finishing-off may be done with a carpenter's chisel held so as to act as a scraper4 ,the turning chisel will answer the same purpose1 but it is a pity to spoil the edge1 which should be always preserved keen and fit for use4 ,if the box is made of soft wood1 scraping will not answer2 the turning chisel must then be made use of1 held as previously1 described4 ,if the cylindrical form is not proposed1 the sides of the box must be left thicker1 and after the cover is fitted on the outside may be moulded by the gouge and chisel1 and tools like #fj and #fh to #gj1 to any desired pattern4 ,the only thing remaining to be done is to cut off the box with the parting tool1 the same precautions being observed which we spoke of in separating the cover4 ,if there should be any defect in the bottom after the work is detached1 the box must be placed in a cup chuck turned to receive it1 and the above defects removed4 ,in hollowing out a piece of solid ivory or similar costly material1 it would be exceedingly wasteful if the central part were removed as in a common box1 by being reduced to small chips4 ,it is possible to remove the whole interior in a solid block1 and with exceedingly trifling loss of material4 ,this is effected by means of side parting tools1 #ga1 #gb1 #gc4 ,a common parting tool is first used and a groove cut therewith in the face of the block to be turned4 ,fig4 #gd represents this face #ge2 the section after the groove is cut the depth of the box required4 ,the shaded part in the centre represents the part to be removed4 ,the smallest parting tool1 ,fig4 #gc1 is now introduced1 the back of the tool being laid across the rest1 so that the crook takes a perpendicular position1 ,a1 ,b1 ,fig4 #gd4 ,when at the bottom of the groove the hook is turned to the left1 so that it may cut a groove underneath the block1 until stopped by its shank4 ,it is then withdrawn and ,fig4 #gb1 and subsequently ,fig4 #ga introduced1 and used in a similar way4 ,in ,fig4 #gf the black line shows the tool in position1 with the under cutting done by it4 ,the sizes are thus increased until the last tool removes the block entire4#c #c ,the side parting tools are sometimes inserted in the centre of the work1 a hole being made for their introduction1 they then cut from within outwards4 ,in this case1 however1 instead of a solid piece a thick ring of the material is detached4 ,illustration3 ,,fig4 #ga1 #gb1 #gc4 ,illustration3 ,,fig4 #gd1 #ge1 #gf1 #gg4 ,we now propose to describe the method of turning a round ball or globe1 and1 to make the work more interesting1 it shall contain a small box4 ,the first thing necessary is to decide upon the diameter4 ,in the present case let it be an inch and a half4 ,turn a cylinder of boxwood a little exceeding this1 and cut off from it rather more than an inch and a half in length4 ,the excess is merely to allow for waste4 ,you will thus have a cylinder whose diameter equals its length4 ,before removing it from the lathe1 mark its centre by a groove with a point tool--subdivide the outer spaces with five lines1 and from the latter remove the corners of the piece1 thus reducing it to the form #gg4 ,test the length and breadth by the callipers and take care that the ends of the cylinder are at right angles to the sides4 ,now place the piece in the chuck in the position shown in the figure1 that is1 at right angles to its original position in the lathe4 ,it must be tested as to truth by holding a point tool on the central line ,e1 ,f4 ,if correctly placed this will only make a dot when the lathe is put in motion4 ,if the piece does not lie evenly the point of the tool will make a small circle--it must then be corrected with a light tap or two1 until it runs evenly4 ,if the inside of the chuck is rubbed with chalk the work will be less liable to slip4 ,the following operation1 however1 must be conducted very gently and with exceeding care1 or a satisfactory result will not be produced4 ,it will be observed that the central line having been marked or cut upon the side of the cylinder is necessarily a circle1 and its revolution on its axis forms a sphere4 ,we have therefore only to cut away the piece truly down to this line to finish what ought to be a perfect globe4 ,bergeron1 however1 justly remarks that although the theory is correct it is next to impossible to manage the tools with sufficient skill to complete in this way a true sphere4 ,one great cause of this difficulty1 is that as the work revolves in its new position the central line is not visible as a line1 but simply becomes the boundary of the sphere4 ,this may be in part done away by making a red line or black one 7red is the best7 instead of a mark with the tool4 ,the work will then appear red as it revolves1 and the gouge and chisel must be used to cut away this red part1 great care being taken only just to remove what appears coloured4 ,thus you will in the end have cut the work away so as barely to remove the line4 ,work from the central part outwards1 and always with exceeding care1 and you will eventually succeed to your satisfaction4 ,it is1 nevertheless1 a very difficult bit of work to finish even fairly well--mainly on account of the great obscurity of your landmark1 the red line4 ,for the more perfect finishing of the above a template of steel may be made like ,fig4 #gh1 with which to test the work--its diameter is equal to that of the sphere1 and it will serve as a gauge or scraper4 ,it should be made of saw plate if intended for the latter purpose1 otherwise sheet brass will answer as well4 ,after the semi-globe has been turned in the first chuck1 it will be necessary to turn another to receive the finished part1 and for the more perfect formation of the same a semicircular template of the same gauge as the concave one first made may be provided1 as the more nicely the ball fits the chuck1 the less chance there will be of the work shifting during the turning of the latter half of the sphere4 ,illustration3 ,,fig4 #gh4 ,in order to obviate the difficulty of following the diametrical line with the cutting tool1 the following contrivance has been suggested to the author by one who has followed lathe work as a profession for many years1 and is an adept at the art4 ,the lathe band is to be slightly slackened by partial untwisting 7a turn or two will suffice71 if of catgut1 so that it will carry round the pulley1 if desired1 but will slip if the hand is placed on the latter4 ,thus1 the tool may be applied1 and a light cut taken1 and the work instantly stopped for examination without stopping the lathe1 as the flywheel continues to revolve all the time4 ,this examination can be repeated1 if necessary1 every few seconds1 by merely placing the hand on the pulley1 and in this way the work being carried on little by little1 a good result is attainable with comparatively little difficulty4 ,the best position for the rest during the above operations will be across the face of the work1 as in hollowing out boxes1 working carefully1 little by little1 from centre to circumference4 ,towards the finish a scraper should be used1 the common carpenter's chisel being as good a tool as any4 ,now to proceed with the box4 ,before removing the finished ball from the chuck1 bore it through with tool ,fig4 #ei1 enlarge with ,fig4 #ea1 and make the hole conical1 unscrew the chuck1 with the ball remaining in it1 and put on another with a piece of boxwood large enough to make a plug to fit this hole4 ,this plug1 when fitted1 is to be hollowed out1 and converted into a box1 like ,fig4 #gi4 ,the latter1 when put in place1 must fit so neatly that only a light circle shows its position4 ,to conceal it still more completely1 a series of circles are to be set at each of the six sides of the ball1 as shown at ,fig4 #hj4 ,to remove the box1 the thumb is placed at the small end1 and pressure made4 ,this forms a neat pocket needle-case1 and may be made of ivory as a present to your lady-love4 ,illustration3 ,,fig4 #gi4 ,illustration3 ,,fig4 #hj4 ,there is no practical difficulty likely to be met with in the above after the round ball is itself made1 unless it may arise in respect of the conical hole4 ,let this be turned out as directed1 until at the furthest 7smallest7 end it will just allow a gauge1 like the annexed figure1 #hj;,a1 to pass through it4 ,illustration3 ,fig4 #hj;,a4 ,having also gauged the large end of the hole to the desired size1 take care to finish the side evenly from one to the other4 ,the gauge may be a disc of tin on a wire1 or1 still better1 a short cylinder of box wood1 on a similar handle1 as there will be a little difficulty in feeling whether the disc is placed at right angles to the axis of the hole4 ,unless1 however1 you desire to work to a pre-arranged exact measurement1 the above precautions will scarcely be necessary1 inasmuch as the hole is first bored1 and the conical plug afterwards fitted to it4 ,the ball may1 therefore1 be taken from the chuck1 each end of the bore measured1 and the plug gauged at each end by the callipers1 and turned to an exact fit4 ,in the above account the unmathematical phrase of six sides of the ball is used for want of a better2 the meaning of the author will1 however1 be evident4 ,,cutting ,,screws4 ,the ambition of amateurs1 especially1 is very commonly centered in a desire to cut screws in the lathe1 and there is good reason for this1 because in the first place there is a difficulty presented which it is pleasant to overcome1 and in the next place1 a screw is of absolute necessity in the greater number of turned works4 ,there is an apparatus of simple but ingenious construction called a screw box1 which is commonly used by carpenters and others who have not attained the skill necessary for chasing screws in the lathe1 and which is very convenient even for those who have obtained this power4 ,a sketch of this is given in ,fig4 #ha4 ,a1 shows the tool complete1 ,b is a view after the top plate has been removed1 showing the knife or cutting tool1 the latter being delineated alone at ,d on a large scale1 ,c is a section4 ,to make this tool1 which is within the power of any person of average skill1 a block of hard wood is first selected1 and drilled with a hole corresponding to the proposed size of the screw to be cut4 ,if no tap is at hand of the desired diameter and pitch1 this block must be mounted in the lathe1 and the thread chased as we shall presently describe4 ,it is absolutely necessary that the block be nicely squared up and level on the face4 ,a small place must then be cut to receive the knife1 the edge of which is so constructed as to form part of the thread cut away to make room for it4 ,it is ,v shaped like ,fig4 ,d1 and very keenly sharpened4 ,the method used to clamp the knife in position1 which is shown in ,fig4 ,d1 permits the cutter to be advanced or withdrawn until its position is accurately determined as above4 ,the top plate of wood is now fitted1 and adjusted--the central hole1 which is not tapped1 but as large as the outside of the screw-thread to be cut1 forming a continuation of that which is tapped in the lower block4 ,a slot b1 ,fig4 ,a1 forms a passage from the knife1 to allow of the escape of the chips4 ,the piece to be cut into a screw should be shaped like ,fig4 #hb4 ,the part a1 will be left plain1 b1 is that on which the thread is to be cut1 and must be truly cylindrical1 and of such size as to just enter the hole in the top plate of the screw box4 ,the part c must pass through the threaded part of the screw box1 not loosely1 but just so as not to damage the threads in the least4 ,the lower part of the central division is sloped off as seen in the sketch4 ,to cut the thread the screw blank is fixed in the vice by its head1 which1 after being turned1 should be planed off at each side4 ,the screw box being then placed upon it the lowest and smallest part of the blank should just project1 as in ,fig4 #hc4 ,this part is intended to insure the perpendicular position of the blank in respect of the screw box4 ,the latter is then turned from left to right until the screw is cut1 which ought to come from the tool clean and smooth4 ,box wood is especially suitable for this purpose4 ,this method is1 of course1 wholly inapplicable to anything but wooden screw bolts1 and for practice the tyro may set to work and make three or four of the following screw clamps1 which are useful to hold pieces of wood that have been glued together4 ,the tap for screwing nuts and the jaws of these clamps1 is similar to that used for metal1 but1 the teeth1 or cutting threads1 are deeper and more pointed4 ,the jaws of the clamps shown in ,figs4 #hd1 #he1 are usually made of beech1 which will take a very fair thread2 or of birch1 which is still better2 and the screws may be made of the same material1 box being too costly and scarce for such purposes4 ,in making these clamps1 there is to be no thread cut on that part at which the handle of the screws project1 nor is there any thread on this part of the bolts1 which pass through a smooth hole in one jaw and lay hold of the other only4 ,other forms will suggest themselves1 but the two given will be found serviceable patterns4 ,illustration3 ,,fig4 #ha4 ,illustration3 ,,fig4 #hc4 ,illustration3 ,,fig4 #hb4 ,illustration3 ,,fig4 #hd4 ,illustration3 ,,fig4 #he4 ,the above method of cutting screws is not of anything like universal application1 nor specially the work of the turner2 we shall now1 therefore1 speak of cutting them by the chasing tool in the lathe4 ,to effect this with certainty requires much care and long practice1 and at first the attempt should never be made on a box or ornamental piece of work1 otherwise finished1 but on a plain cylindrical bolt1 such as those of the clamps just described4 ,for the inside1 or female screw1 the making of chucks will afford endless practice1 and a failure in either of these will be of little importance4 ,the screw tool for male and female threads is represented in ,figs4 #hf and #hg4 ,it is of steel1 and as each tooth inclines in the direction and with the pitch of the screw1 it cannot be made with a file1 but is cut by being held against a revolving tap 7or screw hob1 which is of similar form47 ,there is certainly a defect in the above common form of screw chaser1 and a slight modification1 to be presently described1 will be found easier to use1 and1 in many respects1 easier to make4 ,to cut a thread with the chasing tool1 the top of the rest must be quite level and smooth1 so that the tool may readily slip along it4 ,suppose an outside thread to be required on a cylinder of box or other close grained wood4 ,the rest being firmly fixed so that the upper edge is level with the axis of the piece1 and about half an inch from it1 as ,fig4 #hh1 the tool is advanced to touch the work1 not in a line with the axis1 but so as to bring the part1 a1 in contact with it first1 and the moment the tool is felt to run along1 which it will do as soon as this part of it indents the wood1 the handle is raised a little so that the points of the teeth come into work4 ,the tool in fact must describe the segment of a circle1 as shown by the dotted line4 ,if this is done cleverly the tool will not hitch1 nor produce a drunken thread1 but the latter will come out clean and sharp4 ,it is1 nevertheless1 necessary to practise till the knack of thus chasing a thread is attained1 and1 considering that once acquired1 the necessity of traversing mandrel or other expensive 7and yet more or less defective7 apparatus1 no longer exists1 it is evident that the young aspirant should spare neither time nor patience in becoming an adept in this useful art4 ,illustration3 ,,fig4 #hf4 ,illustration3 ,,fig4 #hg4 ,illustration3 ,,fig4 #hh4 ,one great difficulty in cutting the screw-threads to the top of a box1 or the inside of its cover1 arises from the necessity for stopping short1 and removing the tool instantly as soon as it touches the shoulder1 or the top of the cover4 ,the latter should be made rather deeper than is necessary1 so that there may be a turn or two of screw to spare4 ,this will give more room for the play and removal of the inside chasing tool4 ,the ordinary form of the latter is as shown in ,fig4 #hg1 the part under the plane upper surface 7a7 being either slightly hollowed or flat1 generally the former1 from having been cut by a revolving cylindrical hub4 ,now1 although this form may be suitable for outside screw tools1 which have to work on cylindrical pieces1 it does not appear equally suitable for inside tools1 which are to act on concave work4 ,the writer of this article has experimented upon many patterns of chasing tool1 and has found it perfectly easy to chase an inside thread with an ordinary grooved tap1 which seldom makes a false cut1 or crosses the threads4 ,from this the idea naturally arose of a convex edged tool for inside chasing1 and a concave one for outside work1 as ,fig4 #hi4 ,illustration3 ,,fig4 #hi4 ,illustration3 ,,fig4 #ij4 ,practically1 however1 the convex edge1 ,fig4 #ij1 will answer satisfactorily for an outside cylinder4 ,in order to obtain an efficient cutting edge from this form1 the rounding must be very slight4 ,the out or inside tool is used with a rolling movement on the rest as it advances4 ,if for hard wood1 a notch cut across in the line e1 f1 ,fig4 #ij1 with a saw-file1 will1 by making a partially cutting edge on the convex part1 cause the tool to enter more readily at starting4 ,tools like the above must be necessarily the work of the amateur himself4 ,the regular makers have a great objection to make any tool or machine out of the ordinary routine4 ,hence the same patterns are constantly reproduced year after year1 until some one connected with the manufacture invents an improved form1 or some one else of mechanical genius1 and possessed of means1 registers a new design4 ,amateurs are apt to cavil at this system1 and in some cases it no doubt interferes with1 and checks improvement in tools and machines1 but the evil is almost a matter of necessity4 ,tools are made not singly1 one of each pattern1 but so many score or hundreds of one form are forged out1 and handed over to the grinding and finishing department1 and it would sadly interfere with the system and order of the manufacturer to make a single tool or two for individual purchasers of different pattern to those ordinarily used4 ,if a design is sent in by a retail dealer who can order a hundred or so at his own risk1 the above objection is obviated1 and the new pattern of tool or machine is at once introduced4 ,if1 however1 any new design by an amateur1 being submitted to such men as ,holtzapffel1 ,buck1 ,fenn1 or ,whitworth1 appears to them good and saleable1 they will not only not object to introduce it1 but may possibly give a premium to the inventor4 ,we have thought it necessary to make these remarks to obviate the possible disappointment of amateurs in this respect4 ,it is but natural to suppose that some ingenious device must have long since arisen to obviate the difficulty of thus cutting screws by hand4 ,every turner finds the difficulty1 and few perhaps have failed to try some plan or other to counteract it4 ,there are two methods whereby this can be done3 one by causing the tool to traverse at a given rate according to the proposed pitch of the screw1 the other by giving similar movement to the mandrel1 while the tool remains still4 ,for such work as screwing the lids of boxes1 the traversing mandrel is commonly used1 but for cutting long screws in metal1 the tool is fixed in a slide rest1 and the latter is made to traverse1 if necessary1 the whole length of the lathe bed1 by means of a guide screw driven by suitable gearing put in motion by the mandrel itself1 the speed being adjusted by a series of cog wheels which can be interchanged to cause various rates of motion4 ,the latter method belongs to machine lathes1 and will be treated of hereafter in this series4 ,the author has great pleasure in here introducing a device1 not exactly for cutting1 but for starting the threads of a single1 or double screw1 or1 indeed1 a quadruple one4 ,it is the invention of a gentleman whose nom de plume is ,east ,norfolk ,amateur1 and was by him kindly communicated to the ,english ,mechanic1 of ,june #ba1 #ahfg4 ,the description is here given in his own words3-- ,i think the plan to be described will produce to a certainty any required number of screws and turns to the inch4 ,the screws are entirely cut with a common comb tool1 but started by a revolving cutter set to the required angle1 and applied firmly to the work1 on the ,t-rest4 ,i call it 'the universal screw guide tool1' contrived and made by myself1 and ,i believe will prove as useful to others as it has to me3 the drawing will almost explain the tool4 ,the cutter1 ,a1 is #i_/afths of an inch in diameter1 turned to a cutting edge1 and finely tempered4 ,the stem1 ,b1 in which it revolves1 is round1 and fits into the shoe1 ,c1 having a graduated collar1 ,d1 in front of ,c1 to set the cutter to the required pitch or angle1 the set screw1 ,e1 makes it fast2 having turned a piece of rod1 of brass1 iron1 or steel1 a little above the size necessary1 and supposing a quadruple screw is to be cut having ten turns to the inch1 there would1 of course1 be forty threads when complete2 if one of these four can be truly traced1 the comb tool will easily follow by inserting the outside tooth1 either right or left hand1 as found convenient1 in the line traced1 when the other three will soon appear with perfect accuracy1 provided the first one exactly corresponded to five points of the comb1 which is easily accomplished after a few trials1 and if not successful at first1#d can be removed by a dead flat file several times1 without reducing the rod too much4 ,when found to exactly fit the five points1 the cutter may be applied with more force to leave a good chase for the comb4 ,the ,t-rest requires a smooth surface for the shoe1 ,c1 to slide freely on1 and to be set parallel with the work1 and the tool held at a right angle as it proceeds along the rest1 or the lines formed would be of unequal distance4 ,after a little experience it will be found to work with beautiful accuracy1 and for those who have not screw-guide mandrels1 and are not practised hands at flying common screws1 it will be found a great assistance1 as it sets to anything4 ,i described only the quadruple1 but the same rule applies to all quick screws2 for a double the chase must correspond to three points1 and so on for any number1 that is1 one more point of the comb than the number of screws to be cut1 and for a common one the chase must fit the comb altogether4 #d ,this doubt seems to mar the invention4 ,it is1 however1 on the whole a good design4 ,illustration ,,fig4 #ij and #ia4 ,the above simple apparatus will1 it is believed1 be of great service to those who find difficulty in hand chasing of screws2 it is1 however1 necessary to speak of other methods1 and especially of that so universally used by the turners of ,tunbridge ware--viz41 the traversing mandrel4 ,this is represented in ,fig4 #ia4 ,a is the poppet2 ,b1 the mandrel1 no longer conical at the place where it traverses the collar1 but cylindrical1 and passing through two cylindrical collars4 ,it is prevented from advancing towards the left in its bearings by the shoulder1 ,k1 and in the other direction by a plain cylindrical collar1 or ferrule1 ,c1 which slips over the end1 and is secured by a nut1 ,d4 ,the whole is thus ready for use1 as an ordinary mandrel4 ,to cause it to traverse from left to right1 as it revolves1 the nut and collar1 ,c1 ,d1 are removed1 and a ferrule1 or guide1 ,f1 which has a screw of the desired pitch cut on its edge1 is slipped on the mandrel over a short feather against a shoulder1 where it is retained by a nut or pin4 ,there are several such guide-ferrules supplied with the mandrel of different pitches of screws4 ,the nut ,g is then removed and the piece ,e1 which is of brass or gun metal #c_/h or #a_/b inch in thickness1 with similar screw threads in each of the hollows is attached4 ,this guide is slipped on at ,h1 and secured by replacing the nut4 ,the pin1 which carries the guide1 is frequently made to slide up and down the face of the poppet1 by the action of a screw1 ,m1 working through a brass piece attached to that which carries the pin4 ,it is thus readily lowered out of gear or drawn up again to touch the screw ferule4 ,this is better than a pin screwed to the head of the poppet1 and is always adopted in the best lathes4 ,in the frontispiece is a photograph of this arrangement4 ,this guidepiece acts like a half nut1 and as the mandrel revolves it gears into the ferule and causes the required traverse4 ,a single point tool1 therefore1 held against the work will trace a screw of the same pitch as that of the guides1 and of a length equal to that of the ferule4 ,the above is not intended for cutting long screws1 which would have to be done in successive short lengths1 but for screws of box lids1 chucks1 and similar work it is a most excellent contrivance1 and peculiarly adapted for the use of the amateur4 ,the guide threads in the commoner patterns of these lathes are cut on the mandrel itself1 which is made of greater length than usual1 and these several guides are cut upon the part within the poppet heads1 as ,fig4 #ib1 which represents such a lathe as is sometimes used by gasfitters and brass workers in general4#e ,in the latter it will be noticed that there is added a sustaining screw at the back of the mandrel4 ,this is a good addition1 and indeed almost a necessary one if the lathe is to be used for ordinary rough work1 especially drilling1 as it takes off the pressure which must otherwise come against the shoulder1 ,k1 ,fig4 #ia1 and it must be remembered that these lathes are expensive1 and1 therefore1 ought to be taken care of4 ,the amateur may also be warned against bad work2 none but the first-class makers can turn out a reliable lathe of this description4 ,the collars and mandrel require perfect fitting1 and they must be quite hard1 because there is no possibility of tightening them when worn4 ,they must be kept well oiled1 therefore1 when in use1 and the oil holes in the top of the poppet should be fitted with brass covers1 to prevent any particles of metal1 and especially emery dust1 from working in between collars and mandrel4 ,be sure to have one guide screw of the same pitch as that on the nose of the mandrel1 for the purpose of tapping chucks to fit thereon4 ,in using the traversing mandrel1 either the cord should be slackened so that the pressure of the hand on the pulley may stop the revolution of the work in a moment1 or the flywheel should not be brought into use1 the cord being instead grasped by the left hand1 because it is generally necessary to cut to a shoulder or given point4 ,it is1 however1 possible sometimes so to arrange the guides by insertion of a washer or other expedient as to cause the action to cease of itself at the required point4 ,in a future chapter1 the cutting of long metal screws will be treated in detail1 but before concluding the present chapter1 it may be useful to say a few words concerning the nature of the screw itself as a mechanical expedient4 ,a screw may be defined as a continuous inclined plane--or an inclined plane wound round a cylinder--the pitch being the inclination of the plane1 that is1 the ratio of its height to the length of its base4 ,from the mechanical principle of the inclined plane it follows that the greater number of threads in a given space the greater is the power of the screw when used as in a press1 or to draw along its nut1 as in the slide rest1 in which endlong motion in the screw itself is prevented4 ,it seems1 at first sight1 easy to devise a method for cutting screws of any desired pitch1 but this is far from being the case1 and when it becomes necessary to increase the number of threads to fifty1 sixty1 eighty1 or even more to the inch1 with such accuracy that one turn of the screw shall always produce an equal longitudinal movement of the nut1 the most delicate machinery scarcely suffices for the purpose4 ,the microscope detects and shows errors even in the best work1 and it is questionable whether a perfect screw of any length can be cut by machinery1 as every imperfection in the latter is communicated to the work done by it4 ,if the amateur1 therefore1 requires a screw for a slide rest1 eccentric chuck1 microscope1 or other delicate piece of machinery1 or philosophical instrument1 he had better get it cut by some practical mechanician1 in the possession of the necessary apparatus4 #e ,there should be a collar or shoulder to this mandrel1 the same as at ,k in the other figure4 ,illustration3 ,,fig4 #ia4 ,illustration3 ,,fig4 #ib4 ,in the ,manual ,bergeron is an ingenious contrivance1 by an amateur1 which is worth notice1 although unsuited for any work where extreme accuracy of pitch is required in the screw4 ,the following1 ,fig4 #ic1 is a description3--,the mandrel is made to traverse in its bearings1 as before detailed in this series1 but instead of its motion being governed by guide hubs1 it is dependent on the action of a pair of differential pulleys1 ,b4 ,a bent lever1 ,c1 is pivoted at ,e to the face of the poppet1 having a bit of hardened steel fitted to work in a semicircular groove in the mandrel itself1 and so arranged that on raising the tail or long arm of the lever the mandrel is thrust forward from left to right1 while a reverse action of this lever causes a similar movement in the opposite direction4 ,the movement of the lever is thus regulated3--,at the extreme end of the long arm is a pulley and hook1 as shown in the drawing2 the double1 or differential pulley1 is fixed to the end of the mandrel1 and from the smaller part depends a cord which passes thence through the pulley on the lever1 and is wound round the larger one on the mandrel when its end is secured4 ,on the hook is hung a weight4 ,it will be evident1 on an inspection of the drawing1 that on putting the lathe in motion the cord on the differential pulley will coil itself round the largest part of the same1 and will draw up the end of the lever with a speed proportionate to the difference of diameter between the larger and smaller parts of the double pulley4 ,the short end of the lever will at the same time with similar proportionate motion move the mandrel and work1 and cause the fixed tool to cut a spiral or screw thread on the latter--a good deal of ingenuity is displayed in the above1 and it has the advantage of being easily fitted up1 but it is evident that some alterations and additions would be required to adapt it to any other use but that specified4 ,a contrivance similar to ,fig4 #id1 may in some cases be a sufficient makeshift1 when a more perfect one is not at hand4 ,a screw is here cut on the outside of the chuck1 and a kind of double tool is used1 the tracer which is in contact with the guide thread being adjustable as to its length1 and the cutting tool having a sidelong adjustment as well4 ,the rest being placed between the connecting bar of the tool and the work1 the former will be held with sufficient steadiness to enable the workman to traverse the whole easily by hand4 ,the use of this tool is of course limited1 but the plan is simple and fairly effective4 ,the only really serviceable plan is the slide rest1 to be hereafter described4 ,but one other plan is here added1 which is called ,healey's chuck4 ,the description and sketch are from ,holtzapffel's work1 in which it was however copied from an older treatise4 ,the author1 it must be understood1 has never seen the contrivance himself1 and there is a fault in its principle of construction which must militate against its use except in a very limited degree4 ,since1 however1 ,holtzapffel has considered it worthy of a place in his work1 it is at any rate well to introduce it to the reader1 especially as its defects will not be of great importance in tracing screws of half a dozen threads or so4 ,the apparatus is represented in ,fig4 #ie4 in plan4 ,c is the chuck which carries the work to be screwed1 and ,t is the tool which lies upon ,r1 ,r1 the lathe rest1 that is placed at right angles to the bearers and is always free to move in its socket ,s1 as on a centre1 because the binding screw is either loosened or removed4 ,on the outside of the chuck ,c is cut a coarse guide screw which we will suppose to be right handed4 ,the nut ,n1 ,n1 which fits the screw of the chuck is extended into a long arm1 and the latter communicates with the lathe rest by the connecting rod ,c1 ,c4 ,as the lathe revolves backwards and forwards1 the arm1 ,n 7which is retained horizontally by a guide pin1 ,g71 traverses to and fro1 as regards the chuck and work1 and causes the lathe rest ,r1 ,r1 to oscillate in its socket ,s4 ,the distance ,s1 ,t being half ,s1 ,r1 a right hand screw of half the coarseness of the guide will be cut1 or the tool being nearer to and on the other side of the centre1 ,s1 as in the dotted position ,t1 a finer and left hand screw will be cut4 ,the rod ,c1 ,c1 may be attached indifferently to any part of ,n1 ,n1 but the smallest change of the relation of ,s1 ,t to ,s1 ,r would mar the correspondence of screws cut at different periods1 and therefore ,t and ,r should be united by a swiveljoint capable of being fixed at any part of the lathe rest ,r1 ,r1 which is omitted in ,mr4 ,healey's perspective drawing of the apparatus4 ,illustration3 ,,fig4 #ic4 ,illustration3 ,,fig4 #id4 ,illustration3 ,,fig4 #ie4 ,this is one of the least perfect modes of originating screws1 it should1 therefore1 be only applied to such as are very short1 as1 owing to the variation in the angular relation of the parts the motion given to the tool is not strictly constant nor equable4 ,when in the midway position the several parts should lie exactly at right angles to each other in order as far as possible to avoid the error4 ,the inequality of the threads is imperceptible in a short screw4 ,a little modification of the screw-chuck of ,healey would result in a more correct and serviceable arrangement4 ,the disadvantage1 for instance1 of being obliged to set the ,t of the rest across the face of the work is apparent at once1 and it is difficult to understand how such an arrangement could be made to answer when the work might be of a length to require the support of the back poppet4 ,the following plan1 ,fig4 #if1 would obviate this and the other disadvantages1 and make a more efficient apparatus4 ,b is the chuck with screw chased on the outside1 ,a the nut travelling upon the same4 ,to this is attached a bar ,h1 which passes through the bar ,k1 to which it is clamped by the binding screw visible at ,h4 ,two short pillars1 ,f1 ,f1 are screwed into the bed of the lathe1 in which there might be more than one hole for each to permit the pillars to be fixed at different distances from the line of centre4 ,through slots in these passes the square bar of polished iron or steel ,e1 supporting the traversing rest socket1 ,d1 of which two other views are given at ,figs4 #ig and #ih4 ,it will be evident on inspecting the drawing that as the nut ,a travels to and fro1 it carries with it in a line parallel to the lathe bed the rest socket and ,t4 ,to enable the workman to steady the tool1 the latter should rest against two short pins fixed in the top surface of the rest in holes made for the purpose2 with the aid of these the tool will be made to traverse the work with great ease and regularity4 ,in chasing a right-handed screw1 the tool would have to lie on the left side of the pins1 and the latter would insure its traversing with the rest4 ,a longer ,t 7or half ,t7 being turned in its socket to stand across the face of the work will enable an inside thread to be cut with the ordinary tool either of one or more points4 ,of course1 in this modification of ,healey's chuck1 the screw cut will be of the same pitch as that of the chuck itself2 but as the latter may be of boxwood1 there would be no difficulty in having from three to six with the most generally useful pitches of screws1 as the arm may be screwed into the near side of the nut1 and1 therefore1 it1 and all the other parts of the apparatus1 would answer for the whole set of chucks4 ,if the work to be screwed is merely a box cover1 or some such work where great length of screw is not required1 it is evident that to rig up this kind of contrivance1 or ,healey's1 or indeed anything of similar elaboration1 would appear like summoning a gang of navvies to remove a mole-hill4 ,hence1 if a traversing mandrel cannot be obtained1 by far the simplest plan is the chasing tool used by hand2 it is therefore well worth while to get into the knack of using this tool4 ,to give confidence 7which is essential to success1 the least nervousness generally proving fatal to such work7 the part on which the screw is to be cut may be left larger than will finally be necessary4 ,the screw is then commenced1 and if a failure takes place it is again levelled1 but if1 as is more probable1 the attempt is successful1 the chisel and chase are alternately used1 the cuts of the latter not being obliterated by the former but always left sufficiently deep to form a guide until the desired object is satisfactorily accomplished4 ,illustration3 ,,fig4 #if4 ,illustration3 ,,fig4 #ig4 ,illustration3 ,,fig4 #ih4 ,having treated of screw cutting so far as we are able without trespassing on that section of the present series which is to be devoted to machine work with slide rest and change wheels1 we shall enter on the matter of spirals1 or ,elizabethan twists1 the method of making which was long kept a secret by the trade4 ,these twists are essentially screws of very extended pitch1 and generally rounded threads4 ,the latter sometimes embrace the central cylinder or core1 and sometimes are detached so as to assume a more open form like a corkscrew1 and in the latter case two1 three1 or more threads can be cut1 so that the spirals appear to intertwine4 ,these spirals1 too1 are frequently ornamented with the aid of the eccentric chuck1 and thus the work becomes fit for the adornment of the drawing-rooms of the highest in the land4 ,no turned work can in short exceed in beauty these delicate and elaborate specimens of the turner's art4 ,to commence with a single twist of one thread4 ,a cylinder of the requisite length must first be turned4 ,the number of turns the thread or cord of the spiral is to make in a given space must next be determined4 ,we will suppose the cylinder one foot long1 exclusive of any mouldings or tenons at the ends1 and that the spiral is to make three turns round it1 that is1 one turn in four inches of its length4 ,divide the cylinder into three equal parts by the lines ,b1 ,c1 ,fig4 #ii4 ,next rule equidistant lines ,d1 ,e1 ,f1 along the cylinder in the direction of its length2 in the present case let there be four such lines4 ,the three divisions first made must be subdivided each into four 7always the number of the longitudinal lines74 ,the angles of the parallelograms thus formed must then be connected diagonally as shown in the figure1 which diagonals being continued1 will be found to describe a spiral line4 ,a second similarly constructed spiral determines the thickness of the thread or cord of the twist4 ,these spirals may now be cut with a tenon saw1 and all the material outside the cord carefully removed with the gouge1 so as to form a semicircular hollow between the threads4 ,this cannot be done by putting the treadle and flywheel in motion1 but the work itself must be grasped with the left hand1 while the right holds the gouge upon the rest and guides its edge4 ,after the work has thus been roughed out1 it must be finished by rasps and files1 or by a kind of plane with a semicircular cutting edge4 ,while the latter is being used1 the flywheel must be brought into action1 so that the work may be made to revolve with sufficient rapidity to ensure a clean and smooth cut4 ,a hollow plane may be used to round the cord of the twist1 and the whole finished with glass paper and polished4 ,illustration ,,fig4 #ii4 ,the kind of plane named was designed by a regular workman for his own use1 and was made thus and grasped in the fist1 or rather hollow of the hand4 ,the iron was like c1 sharp at one edge1 the block of wood being slightly bevelled off in front of the cutting edge4 ,the workman1 who made scores of these twisted works for the trade1 of all dimensions1 would run this along the hollows1 while the lathe was in motion1 with great speed and accuracy4 ,he marked the spirals as described1 and then grasping the work in the left hand1 and the gouge in the right1 turning the work round with the former 7the cord thrown off the wheel71 he cut out the wood boldly in large pieces with little apparent care1 and perfect ease4 ,then came the plane described above4 ,fig4 #ajj shows a simple spiral thus made4 ,if the piece to be turned is dark it is not easy thus to mark out the divisions4 ,in that case the following method will answer equally well4 ,it is the plan used and contrived by the writer1#f and specially handy when a number of similar twists are to be cut1 as in ornamented pieces of furniture4 ,a1 ,fig4 #aja1 is a straight edge of hard wood1 through which1 at any given angle 7regulated by the number of turns the cord is desired to make in a given length of cylinder71 a knife edge is fixed4 ,if this is held as in the figure1 and the blade is pressed down upon the cylinder to be cut1 the lathe being put in motion1 a very correct spiral will be traced1 which can be at once deepened by a tenon saw as before4 ,the thickness of the cord being determined it only remains to place this tool again upon the work so that the second line shall be traced at the required distance from the first4 ,a second1 or any number of cords1 may be thus traced in succession parallel to each other by this simple method4 ,by a slight modification of this instrument1 which allows the knife to be clamped at any desired angle with the straight edge1 the inclination of the cords1 and1 consequently1 the pitch of the spiral can be varied at pleasure1 and a second blade can be added to trace the second line1 determining the thickness of the cord with one movement of the tool along the cylinder4 ,the edge of the knife may be across the rest1 the piece of wood just overlapping the ,t on the side next the workman1 if the blade is long enough to reach across the work when thus held4 ,the tool will be steadier and perhaps more easy of management in this position4 ,one hand should then lightly press the back of the knife1 while the other retains the wood against the rest as a straight edge4 ,east ,norfolk ,amateur's design of a screw guide is on the same principle1 the only difference being the substitution of a revolving instead of a fixed knife edge4 ,in using either it requires some care to allow the tool free traverse1 as the least check would spoil the thread4 #f ,a similar plan is noticed in ,holtzapffel's mechanical manipulation1 which the writer had not seen4 ,it is satisfactory to him to find the method thus authorised4 ,illustration3 ,,fig4 #ajj4 ,illustration3 ,,fig4 #aja4 ,the next class of spirals is that in which no central core exists1 but the coils stand separate and distinct1 two or more rising from the same base4 ,the coils are sometimes flat1 sometimes rounded1 and still more frequently1 in the best work1 exquisitely1 and 7as a casual spectator would say7 impossibly carved4 ,the process is as follows3--,turn a cylinder of ivory or hard wood1 forming at the end any required mouldings as a base and capital4 ,determine the number of coils and the pitch1 and by one of the previous methods mark out the same4 ,the cylinder is now to be bored out from end to end1 leaving sufficient for the thickness of the required cords4 ,this bore may with advantage be slightly larger at one end than at the other1 so that a mandrel of wood may be fitted into it1 to be afterwards easily withdrawn4 ,this will certainly be necessary if the ivory cords are to be of light substance1 as they require support to enable them to bear the action of the tool4 ,after the cylinder has been bored as above directed1 let a mandrel of common wood be inserted1 and the lines1 marked as shown1 be cut quite through4 ,the intermediate parts between the intended threads must then be removed carefully 7with a round rasp1 if of ivory7 with any convenient tool if of wood4 ,the cords must then in a similar way be rounded or otherwise moulded1 and afterwards the common and now damaged mandrel removed4 ,in the case of ivory the piece of work will not only be strengthened by the insertion of a polished mandrel of ebony1 but its appearance will be improved4 ,sometimes1 however1 it may be preferable to line it with red velvet or silk1 or it may be left entirely open4 ,the further ornamentation of the cords1 depending on the eccentric chuck or eccentric cutters1 will not be described in the present paper4 ,these open spirals are worth a vast amount of patience and trouble1 which their elegant appearance when finished will amply repay4 ,the reader is not to suppose that this method of cutting spirals by rasp and file is the only or best method1 especially when ivory is the substance operated upon4 ,further on will be described various modes of accomplishing the same ends by self-acting machinery1 and by the spiral apparatus designed for use with the ordinary lathe1 but all these need the slide rest1 whereas it is quite possible in the foregoing manner to make spirals by hand tools alone1 which for correctness and finish may vie with those which may have been worked with more elaborate and costly apparatus4 ,before quitting the subject of plain hand turning in wood1 a few more words may be necessary in respect of certain details of lathe manipulation1 foremost among which comes ,chucking work4 ,this is often carelessly done1 especially by amateurs1 who1 in consequence1 are frequently annoyed by the shifting of the material under the influence of the cutting tool4 ,if this is hard and valuable--as are many of the best woods for ornamental turning--the fork or prong chuck will not enter sufficiently to sustain the piece1 and at the same time the stuff is too valuable to allow of the waste incurred in screwing it direct to the mandrel1 or inserting it sufficiently far into a brass cup chuck4 ,in such cases the best plan is to screw a piece of common wood upon the mandrel1 face it truly1 and cut a few shallow concentric circles upon the end thus levelled1 both for the purpose of a guide to centrality1 and also to give a hold to the glue by which the more precious material is to be attached to it4 ,for this purpose1 both chuck and work are to be well warmed1 and the glue--boiling hot--brushed upon the parts to be united4 ,the latter are then to be rubbed together a few seconds1 and when the piece to be turned runs truly1 the back poppet with boring flange attached--if the right hand end of the piece is level1 otherwise1 the point allowed to remain--is to be brought up and screwed as a clamp against it till dry4 ,this process requires time1 but is well worth the trouble1 as the material will be securely held1 and can be safely operated on4 ,none but those who have had to contend personally with a tyro's difficulties1 and have1 in consequence1 seen the work shift in the chuck when nearly completed1 can truly appreciate the advantages of efficient chucking4 ,in the case detailed1 there is absolutely no waste of material1 no possibility of the work becoming loose or out of truth2 and the ornamentation by eccentric cutters1 drills1 and so forth1 can be proceeded with1 and carried out with that confidence which never fails to promote good workmanship4 ,even with the above arrangement the back poppet should be used while the excrescences are turned down1 and retained as long as the gouge has to be used in bringing the design into an approximation to its intended form4 ,this should be removed1 however1 before taking the final cut1 as the work will generally seem to drop a little when the support is taken away1 in consequence of the mandrel1 which has been forced against the back centre1 returning to its place in the collar4 ,pieces of six or seven inches in length1 and of one or two inches diameter1 requiring to be hollowed out1 may frequently be turned by reversing the usual method and boring out the interior1 previous to shaping the outside4 ,a case for pencils1 for instance1 or a bodkin case1 may be thus worked3--,mount in the square hole chuck1 an ,american screw auger1 sets of which are now to be had beautifully finished and polished4 ,the kind meant has a scooping kind of edge above the screw1 ,fig4 #ajb1 and cuts cleanly and rapidly4 ,the piece of wood--soft wood alone is meant--is brought against the tool1 being grasped by the left hand1 while the back centre1 with flange1 is steadily advanced with the right hand against the opposite end4 ,this auger will run straight through several inches without requiring to be withdrawn1 as the borings pass freely along the polished threads of the instrument and escape4 ,if necessary1 however1 it can be readily withdrawn by reversing the action of the lathe1 and replaced without difficulty4 ,the piece thus bored may then be mounted in the lathe and finished on the outside4 ,to do this satisfactorily1 an arrangement is requisite by which the centrality of bore is insured1 else in the process of cutting the external surface1 the material will1 in all probability1 be cut through in one part1 while in another it will remain of considerable thickness4 ,if the piece is bored quite through1 so as to become a tube1 ,fig4 #ajc will be satisfactory1 as the cones preserve centrality1 whilst the use of the carrier will prevent the necessity of screwing the cones up so tightly as to endanger splitting the wood4 ,this is the best way to chuck small cylinders and brass tubes4 ,the more obtuse the angle of the cones the better4 ,illustration3 ,,fig4 #ajb4 ,illustration3 ,,fig4 #ajc4 ,illustration3 ,,fig4 #ajd4 ,in this method the bottom of the case must be turned as a plug and glued into its place4 ,if the bottom of the case is left solid1 an arrangement like ,fig4 #ajd will answer well4 ,the plug chuck1 ,a1 must not be at all conical1 and the part that enters the work must be at least an inch long4 ,if this is attended to1 and the face of the work and of the chuck is square1 the tube will be truly centred1 only requiring the back poppet to take off the strain upon ,a1 when the tool is applied4 ,if ,a is chalked1 there will be no slipping1 provided it has been accurately fitted4 ,observe1 nevertheless1 that as a general rule1 hollow work should be placed inside and not upon a chuck1 unless you have to work upon the whole exterior surface4 ,by this plan1 there will be no likelihood of splitting the object1 an undesirable consummation which not unfrequently takes place when the contrary method is pursued4 ,thin discs of wood or brass are most conveniently turned upon a face-plate1 to which they can be attached by turners' cement1 already described4 ,if1 however1 one surface only has to be worked1 and the plate is not of less thickness than #a_/hth of an inch1 it may be mounted on a flat chuck with small projecting points1 the back poppet being used to keep it firmly against the face of the chuck4 ,even a plate of brass may be thus turned if placed first of all against the chuck and gently tapped so as to mark the position of the points1 and then drilled to suit them4 ,bread-platters are thus easily chucked1 first of all face downwards1 and then reversed with the bottom against the points1 so that in the latter position1 the chisel or broad may be applied to the face and the marks removed4 ,the larger designs on these platters are carved by hand after their removal from the lathe1 and the small figures forming the ground1 which often appear round the main design1 are made by figured punches4 ,chucking ,egg ,shells3--,the method of doing this so as to enable the turner to cut the shell evenly in two parts1 is given by ,holtzapffel1 in his ,mechanical ,manipulation1 and has been copied elsewhere4 ,it is ingenious and effective4 ,the object is simply to obtain a pair of delicate vases1 to be edged with ivory1 and mounted on a pedestal1 as a curiosity4 ,the following account is from the pen of the inventor1 ,mr4 ,g4 ,d4 ,kittoe1 as communicated to ,mr4 ,holtzapffel3--,in the accompanying figure--,fig4 #aje--;is represented the nose of a lathe1 with an egg chucked ready for cutting4 ,fig4 #ajf is the chuck used first to prepare the egg1 to be mounted in the above way4 ,the latter is generally termed a spring chuck1 and is made by rolling stout paper with glue upon a metal or hardwood cylinder1 the surface of which has been greased to prevent the paper sticking to it1 and upon which it must remain until perfectly dry1 when it may be removed and cut or turned in the lathe as occasion may require4 ,n4,b4 ,nothing is said in the above account of the evident necessity of fixing the paper cylinder to a wooden block1 in which a screw must be cut to mount it on the nose of the lathe4 ,this sort of chuck is very light--easily made and well adapted for the brittle material it is intended to hold4 ,before fixing the egg in it1 the inner surface should be rubbed with some adhesive substance 7common diachylon answers exceedingly well72 when this is done the egg should be carefully placed in the chuck1 the lathe being slowly kept in motion by one hand whilst with the other the operator must adjust its position until he observes that it runs perfectly true1 then1 with a sharp pointed tool he must mark the centre and drill a hole sufficiently large for the wire in the chuck1 ,fig4 #aje1 to pass freely through4 ,when this is done the egg must be reversed1 and the same operation repeated on the opposite end1 its contents must then be removed by blowing carefully through it4 ,it is now ready for cutting1 for which purpose it must be fixed in the chuck1 ,fig4 #aje4 ,a is a chuck of box or hard wood having a recess turned in it at a1 b1 into which is fitted a piece of cork as a soft substance for the egg to rest against4 ,b is a small cup of wood with a piece of cork fitted into it serving the same purpose as that in ,a4 ,a piece of brass1 d1 is to be firmly screwed into the chuck ,a1 and into this a steel wire screwed on the outer end1 on which a small brass nut e is fitted to work freely in a recess in the piece ,b4 ,when the egg is threaded on the wire through the holes previously made in it1 this nut is to be gradually tightened up until it presses the cup ,b against the egg sufficiently to hold it steady and firm enough to resist the action of a finely-pointed graver used to cut it4 ,the tool requires to be held very lightly1 as a little undue violence would crush the shell4 ,neither should the latter be pinched unduly tight in the chuck1 as otherwise when the point of the tool divides the shell the two parts might spring together1 and be destroyed by the pressure4 ,it requires some delicacy of hand to attach the rings to the edges of the shell to constitute the fitting4 ,the foot and top ornaments are fixed by very fine ivory screws1 the heads of which are inserted within the shell4 ,illustration3 ,,fig4 #aje4 ,illustration3 ,,fig4 #ajf4 ,box wood is decidedly the best material for ordinary chucks1 as it takes a screw almost as well as brass1 is pleasant to work1 holds the material firmly1 and is of good appearance1 which last is not unimportant to those who possess good lathes1 and like to see everything in decent order about the workshop1 and it is certain that a disorderly workman will commonly produce slovenly work4 ,this wood1 however1 though tolerably plentiful1 is sufficiently costly to be worth preserving1 and by a little management chucks may be made to answer for a longer period than might be at first supposed4 ,a chuck1 for instance1 too large to hold the work1 may be plugged with a worn-out chuck of smaller bore1 or with wood of inferior character1 to save the necessity for hollowing out a new piece of box wood4 ,the latter material1 moreover1 excellent as it is1 may be replaced by other kinds of wood1 provided the latter will bear a good screw4 ,beech1 if dry1 will answer very well for the purpose4 ,pear is tough and screws well4 ,apple is little inferior4 ,ilex or evergreen oak is sufficiently hard and tough and will be found quite satisfactory4 ,elder of large size is good1 and screws well4 ,sycamore screws well1 but is not always equally tough4 ,all hollow or cup chucks should be furnished with rings of iron or brass to prevent splitting4 ,about six sizes of rings will suffice for a great number of chucks4 ,bergeron1 speaking of the barrel stave chucks already alluded to1 prefers the encircling rings plain and not screwed4 ,he gives the following reason3--,if a piece of work entered in such a chuck does not run quite truly1 a tap on the ring in the proper place will1 by closing the sawgates more in that part1 rectify the error1 whereas with a screwed ring this is impossible4 ,there is reason in this1 but at the same time it would be easy to unscrew the ring a turn or so1 give a light tap to the work1 test its position by putting the lathe in motion1 and when true fix it securely by screwing up the ring4 ,there is1 however1 one precaution to be taken in making these useful chucks--namely1 to cut the staves of equal width1 else they will not yield equally to pressure1 and the work will not be so readily centred truly4 ,a grip chuck of inexpensive make 7one additional pattern of which is introduced from a design by contributors to the ,english ,mechanic7 should always be provided4 ,a rough block of ivory for instance may be seized in its jaws1 and the exterior useless part cut off by a parting tool as a ring1 leaving the nicely rounded material ready for chucking4 ,ivory nuts or corosos which are peculiarly awkwardly shaped for mounting in the lathe1 may also be thus seized1 and one portion faced up and rounded so as to allow of being fixed on a face chuck by glue or cement1 or fitted into a cup chuck4 ,rough pieces1 too1 thus mounted may be faced up1 bored and tapped to fit the mandrel as chucks1 and a thousand similar works may thus be handled4 ,the simple grip chuck in question is important as having the very useful addition of a centre point which the writer would1 if he did not abominate and eschew puns1 direct attention to1 as the chief point of interest--,i call it1 says the inventor1 a ,universal ,self-,centering ,grip ,chuck4 ,the drawings #a1 #b1 and #c1 almost speak for themselves1 to practical turners4 ,illustration3 ,,fig47drawing7 #b4 ,illustration3 ,,fig47drawing7 #a4 ,illustration3 ,,fig47drawing7 #c4 #a1 is an elevation of one of the grips4 #b1 a section through centre of chuck4 #c1 a side section of ditto4 ,the body of the chuck is made of cast iron1 to screw on to the mandrel2 and the grips1 #a1 are moved simultaneously by a right and left-handed screw acting in a circular groove4 ,the jaws of the grip are serrated and tempered1 the same as in ordinary vices4 ,in the centre of the grips1 when closed1 a three-sixteenth hole is bored true to the centre of the lathe4 ,behind this there is a true centre point screwed into the body of the chuck1 as marked at a4 ,the above hole and this centre point are to be particularly attended to1 as on their truism depends the correctness of your work4 ,if ,i want to turn a solid cylinder ,i make the usual centre at each end2 put one on the above centre point and the other on the back centre of lathe1 and then screw up the grips tight2 but if the work is short you need not apply the above centre point or the back centre1 as the grips are alone sufficient4 ,the hole in the jaws of the grips admit of any kind of drill or other tool being put into them without using any centres1 and the grips will admit anything up to two inches4 ,in fact1 ,i do almost every sort of thing with this chuck1 and ,i think amateurs1 if not others1 will find it a most valuable and handy contrivance4 ,fig4 #ajh1 ,a and ,b1 represents a modified form--a chuck already spoken of and recommended for ordinary plain turning1 in which the work is supported at both ends4 ,the present form is to a great extent self-centering and will hold the work also without the saw-cuts otherwise needed1 the sharp edges of the double fork entering the work with the pressure caused by the back centre4 ,the chuck is useful not only for ordinary work1 but for re-mounting pieces centrally1 which it may have been necessary to remove when partly finished1 and to return to the lathe for completion4 ,a still further addition to this chuck of a steel point sliding through the centre1 as in the section1 ,fig4 #aji1 makes it a very complete and serviceable apparatus1 as by this means it is easy to reverse the work without destroying its centrality4 ,the point is intended1 as in the chuck of ,wilcox1 to slide back stiffly 7being if necessary kept up by a spiral spring as shown71 as it is only intended as a guide to assist in mounting the piece4 ,if the mandrel is not bored the chuck must be long enough to receive the pointed wire within its substance4 ,this will be found in every way a most serviceable chuck4 ,it may be of iron or brass1 or even of wood1 if a round plate of brass is mounted on its face1 to which the holding pieces can be soldered or brazed4 ,illustration3 ,,fig4 #ajh4 ,illustration3 ,,fig4 #aji4 ,,hollowing ,,out ,,soft ,,wood4 ,this is done1 as already described1 by the regular soft wood turners in ,tunbridge and elsewhere1 by means of hook tools4 ,a great number of workmen1 however1 use only the gouge1 and for boring out chucks1 hollowing boxes1 small bowls1 and similar work1 the latter tool will be found effectual if rightly held and carefully managed4 ,it must not1 however1 be applied to the inner surface of the work at the point usual with scraping tools1 but beyond the centre1 ,fig4 #aji;,a4 ,the rest1 ,b1 does not require to be turned across the face of the work1 but remains parallel to the bed of the lathe4 ,the blade of the gouge is to press against the near side of the hollow as the work proceeds1 which considerably aids in securing the position of the tool4 ,the back of the gouge is to face the bottom of the hollow 7next the mandrel71 but the tool is generally rolled on the rest a little1 so that its hollow side is often more or less below1 towards the lathe bed1 and the point is also lightly raised as it approaches the finish of the cut4 ,begin with the tool almost horizontal1 and at the centre of the piece1 the back against the wood1 and1 depressing the handle as the shaving is removed1 finish at the top outer edge of the hollow1 rolling over the tool1 so that it shall leave the work with its back upwards and hollow downwards4 ,thus used it will not stick in its course1 and1 after a few trials1 will be found to cut out the wood cleanly and rapidly4 ,illustration3 ,,fig4 #aji;,a4 ,another grip chuck1 or self-centering scroll chuck may here be introduced1 from the source of information previously alluded to4 ,the writer thus describes it-- ,,american ,,scroll ,,chuck4 ,this chuck is made upon the same principle as the ,warwick ,drill ,chuck--namely1 a flat spiral so acting on three jaws sliding in radial grooves as to make them recede from the centre to admit any object between certain sizes1 and then to be tightened upon it4 ,fig4 #a is a plan of a #d-;inch chuck4 ,fig4 #b is a vertical section of the same4 ,fig4 #c is a view of the outside of the chuck1 and ,fig4 #d is a separate section of the principal part a1 a1 taken through the line z1 z 7,fig4 #a74 ,in ,fig4 #b1 a1 a is this piece1 b1 b1 has the spiral cut on it which actuates the jaws #a1 #b1 #c 7,fig4 #a71 c1 c screws on the piece a1 a to keep b1 b in its place and d1 d is the plate which screws on the mandrel1 and which is fixed to c1 c1 by three countersunk screws1 one of which is shown in section4 ,illustration3 ,,fig4 #a4 ,illustration3 ,,fig4 #b4 ,illustration3 ,,fig4 #c4 ,illustration3 ,,fig4 #d4 ,if the foregoing observations are carefully studied the further practice of plain hand-turning in wood will not be difficult1 and we shall proceed to speak of metal turning1 before passing to a description of the ,slide ,rest and other apparatus usually added to the lathe4 ,we may1 however1 observe here1 that1 for ivory and hard wood--especially the former1 the first roughing down cannot be done with the gouge4 ,a point or small round-ended tool must in these cases take its place1 to be succeeded by one or more of those tools which rather scrape than cut1 as described in detailing the process of hollowing out boxes and similar work4 ,,metal ,,turning ,,by ,,hand ,,tools4 ,the first requisite for the above work is a well made and sharp tool1 for1 strange as it may appear1 a keen edge is as necessary for making good work in metal as in turning wood4 ,the principle of this cutting edge must be well understood1 and this has been well explained by ,nasmyth and others4 ,the remarks of the above eminent mechanic upon this subject1 as also those of ,professor ,willis and ,mr4 ,babbage have been embodied in a very excellent paper by ,dodsworth ,haydon1 ,esq41 an amateur1 and will be found in the ,appendix to this work4 ,the whole principle of the formation and application of cutting tools is explained in that paper1 so that it only remains to treat briefly of a few special forms of tools which are required for metal-turning in the lathe1 whether by hand or by the aid of the slide-rest4 ,in the first place1 however1 a word or two may be necessary as to the kind or quality of steel required for such tools4 ,what is called ,blister steel may be at once passed over as unfit for the formation of tools--it is1 however1 the raw material 7so to speak7 from which1 by the process of reheating and welding1 the next quality1 called ,shear steel1 is made4 ,when bars of this are similarly heated and again welded into a homogeneous mass under the tilt-hammer or between rollers1 double shear-steel is made1 which is of extensive use for cutting tools1 and must1 moreover1 of necessity be used in almost every case where there is to be an iron shank1 for economy's sake1 the steel being then welded to the iron1 and forming that part of the tool intended for the edge4 ,the third and best kind of all is ,cast-steel1 formed of blister steel1 melted at an intense heat and run into iron moulds4 ,this1 however1 can be welded only with great difficulty1 and hence the whole tool1 whatever its length1 must be of the same material4 ,this can be purchased in bars of a convenient size of round1 triangular1 square1 or other section1 and needs only the careful use of the hammer1 file1 and grindstone to become a tool of any required pattern4 ,it would be very advantageous to an amateur to master the art of forging in a small way to enable him to make his own tools1 for he may sometimes require them of unusual form1 and if he lives far from a manufacturing town he will find it very difficult to get them fashioned to his liking4 ,cast-steel will not allow of the welding heat applied to iron--it will burn1 and cannot then be made to recover its proper consistency1 and is for ever useless for the purpose in question4 ,double shear will take a moderate white heat1 while cast-steel must not be brought to a higher temperature than that indicated by bright red--a point never to be forgotten when shaping a tool at the forge4 ,there are in every workshop a number of files laid aside as worn out4 ,these being made of the best cast-steel1 are invaluable to the turner in metal1 as they supply the best material for his tools at no cost whatever4 ,to begin with the saw files 7called1 by a horrible perversion of mathematical definition1 three square74 ,here you possess a tool at once for the mere trouble of grinding off the teeth and reducing the sides to a smooth surface4 ,each angle is equally useful--each #fj1 which1 as the paper above alluded to demonstrates1 is the best angle for cutting iron4 ,on brass1 however1 its use is by no means to be recommended1 being1 as ,holtzapffel remarks1 too penetrative and disposed to dig into the work4 ,it is to be used upon iron in the position shown in ,fig4 #aaj1 where ,a is the rest1 ,b the cross section of the tool1 ,c the diametrical line4 ,the side1 of which ,d is a continuation1 is to form very nearly a tangent to the circumference of the work1 being1 as explained in the ,appendix1 only #c from that position4 ,worn out square files being of rectangular section1 are exactly suited for brass turning1 for which metal a cutting edge is required of #hj to #ij1 the former for the first or roughing down cut1 the latter for finishing4 ,the position of such tool is shown in ,fig4 #aaa4 ,illustration3 ,,fig4 #aaj4 ,illustration3 ,,fig4 #aaa4 ,the flat files are not altogether so useful for making turning tools as those alluded to2 they are too thin in proportion to their breadth4 ,their sides1 moreover1 generally speaking1 are not rectilineal1 but curved1 so that they are more fit for grinding off at the ends to form brass-turning tools with rectangular edges4 ,they may1 however1 by careful forging1 be made to assume a square section1 and thence be formed as desired2 but a rectangular bar of steel1 ready-made1 is then to be preferred4 ,a round or rat's tail file is of far greater service than the last-named--not1 indeed1 in its own shape1 for the reasons stated by ,mr4 ,haydon1 but as being capable1 with very little labour at the forge1 of being converted into a bar of square section4 ,the first tool to be made from such a bar is the graver1 the tool of the watchmaker1 and not less useful to the general mechanician4 ,this is formed by grinding the end of a square bar diagonally1 so as to produce a lozenge-shaped face4 ,the angle to be preferred in this operation is #de1 which will give two cutting edges of #fj4 ,the latter may be varied at pleasure by varying the angle at which this face is ground1 as explained in the chapter which treats upon this question4 ,the graver will do all kinds of outside work1 light or heavy1 as it may be made of any size4 ,it is represented in ,fig4 #aab4 ,fig4 #aac is the heel-tool shown in position for work2 #aad and #aae1 two forms of nail-head tool very commonly used1 but both requiring great attention to the angles of the cutting edge to become effective4 ,all the above are for outside work1 and are to be so held that the side next to the work--the sole of the tool in ,fig4 #aac--;forms very nearly a tangent to the work--a position1 as ,holtzapffel remarks1 strangely similar to that required by the soft wood chisel and similar tools4 ,the heel-tool1 indeed1 if more keenly sharpened1 will cut soft wood 7on the face7 with great rapidity1 and is in principle similar to the broads used for that purpose4 ,it is1 however1 an unsafe tool1 owing to its great tendency to dig into the work4 ,it is a good plan to make extensive use of various shapes of hand-tool before passing to the slide-rest1 because the hand feels exactly the resistance which the tool meets with1 and the best form and position is thus practically tested1 and will be found to bear out to the utmost the theory advanced in this work1 and founded on mathematical truths worked out and applied by ,willis1 ,babbage1 and others4 ,illustration3 ,,fig4 #aab4 ,illustration3 ,,fig4 #aac4 ,illustration3 ,,fig4 #aad4 ,illustration3 ,,fig4 #aae4 ,inside tools must of course be made upon the same principles as the last1 the particular form alone being modified to enable the cutting edges to penetrate into the various nooks and corners that may occur in such work4 ,the inside tool for iron 7,fig4 #aaf71 with cutting angles of #fj1 is of a general and useful pattern4 ,it must be so curved and so placed that both cutting edges come into action1 one on the face and one on the side of the cut1 a condition explained in the ,appendix as essential to all good work4 ,it being quite impossible to cut metal like wood1 and necessary to allow sufficient time for such work1 a pointed tool is in most cases preferable to one of a semicircular or rectangular form of edge1 and the greater part of the heavy work done in large factories is thus executed4 ,inasmuch1 however1 as such a tool1 well formed on correct principles1 may be made to take a tolerably deep cut1 the shaving detached will be of sufficient thickness1 and consequently sufficient width to reduce work a satisfactory quantity at each cut4 ,the cut1 too1 must be continuous wherever possible1 the tool being slowly and steadily advanced the whole of the acquired distance without being removed1 and then re-entered for a second cut4 ,the result should be a smooth1 even surface1 and that great exertion is not required when thus working with hand-tools is sufficiently evidenced by a remark of ,mr4 ,haydon to the writer1 ,i have often detached1 with a graver alone1 a tolerably thick shaving of iron1 two feet and more in length4 ,from what has been said1 it will be understood that in hollowing out a piece of metal such as a chuck1 the tool should not be made with a long cutting edge1 such as would be used if it were intended to scrape the whole depth of the side4 ,a broad shaving is not to be thus aimed at1 nor is the inside only to be thus attacked1 but the tool advanced gradually inwards from the face of the work till it reaches the bottom1 thus 7to repeat the important point again7 cutting at the same time the front and side of the shaving4 ,the half-round or cylinder-boring bit already described is1 of course1 an inside turning tool1 but is used with the aid of the back centre4 ,in principle it follows other inside tools1 the end being bevelled or sloped off #c1 and the side being #ij4 ,the latter is to be regarded as a blunt cutting tool1 being the largest angle that can be used2 but1 nevertheless1 this bit must be regarded as cutting in the two required directions--forward and sideways4 ,if a regular ,goniometer for measuring angles is not to be obtained1 nor any apparatus for grinding a tool to the required bevel1 an addition to ,nasmyth's tool-gauge1 described in the ,appendix1 may be made by constructing in tin a set of templates1 with the angles marked upon them4 ,the easiest way is to mount on the lathe a few round sheets of tin1 and mark the degrees by the division-plate1 the outer circle of which contains #cfj4 ,the tin may then have pieces cut out1 as shown in ,fig4 #aag1 to be applied as gauges over the ends of the tool1 or solid pieces of the required sections 7those which are removed in forming the above7 may be retained4 ,it will1 perhaps1 be as well to finish up both neatly1 taking care to mark the angles on each4 ,the degrees most required are1 as explained1 #ij1 #fj1 #hj1 and #c2 but intermediate numbers may be prepared1 and will often be found convenient4 ,an inside tool for brass must retain the angles #hj to #ij1 the latter acting as a scraping tool to put a finish to the interior of work roughed out by a tool of the lesser angle4 ,there are not many forms in general vogue1 for brass work1 whether internal or external4 ,the round1 the flat1 and the point tools 7,figs4 #aah to #aba7 are more or less capable of hollowing out work1 as well as surfacing4 ,with the first ground to an angle of #hj1 brass chucks can be hollowed1 and1 with the second at #ij1 finished2 and if there chance to be any internal angles out of reach by the point-tool1 it is only necessary to use a similar one bent round at the end towards the left4 ,much of the turner's success in brass work depends upon the quality of the metal1 which is often very hard and unequal in texture and perhaps blown and honey-combed4 ,it is always the best plan to send patterns of any work of importance to some well-known firm1 instead of trusting to a country foundry1 whose business1 if worthy the name1 is generally iron work1 and who only run brass once in a way1 and make a terrible mess of it1 too4 ,the same may be said respecting iron castings4 ,it is worth while1 as an experiment1 to test with turning tools the quality of a country casting1 pulley1 or what not1 by the side of a similar work really made of malleable iron1 such as is now so extensively used by the sewing-machine makers4 ,tools that will stand the first and make good work deserve a place in the ,british ,museum1 with a portrait of the turner6 ,illustration3 ,,fig4 #aaf4 ,illustration3 ,,fig4 #aag4 ,illustration3 ,,fig4 #aah1 #aai1 #abj1 #aba4 ,for light brass work1 such as small model engines now so generally sold1 a description of lathe may be used of which no mention has yet been made--namely1 a bar lathe ,fig4 #abb4 ,such a tool may be made for #c or #d1 and will be found sufficient for such work as specified4 ,illustration3 ,,fig4 #abb4 ,in place of the double bed a triangular bar of cast iron is used1 on which the poppets slide1 and are clamped4 ,d shows one of two sockets with feet which hold the ends of the bar1 and by which the lathe can be mounted on any stout plank or on the window sill4 ,the pulley ,a is made for a strap1 because this allows of a plain flywheel1 which is much cheaper than those which are bevelled and turned4 ,the rest is shown at ,e and ,f4 ,the part ,e slides upon the bar like the poppet--at the top is a dovetailed groove to receive the slide ,f1 which carries the socket for the tee1 and is fixed by a turn of the screw seen on the top of it4 ,there is much to be said in favour of triangle bar lathes1 they are very stiff1 and can be fixed anywhere4 ,the flywheel can be supported on a separate frame1 which is an excellent plan1 for the jerk of the treadle and crank is not communicated to the poppets and mandrel4 ,in ,maudslay's triangle bar lathe1 which was made for amateurs1 a slide rest was attached1 and the whole work was first class--of late they have gone out of fashion1 but are nevertheless good tools4 ,fig4 #abc represents another very simple form of lathe for turning small articles of brass4 ,it may be said to be one remove from the watchmaker's bow lathe1 as it has no true mandrel or treadle2 the small flywheel being attached to an arm at the back and worked by hand4 ,the left hand is used for the latter purpose while the tool is held in the right4 ,through a tapped hole in the left hand poppet passes a steel pin shown at ,e1 on a larger scale2 this screws into the poppet after passing through a brass pulley ,b2 this bolt ends in a point1 and an arm fixed into the pulley becomes a dog to act against a carrier screwed on to the work as in turning iron4 ,thus the mandrel and point are fixtures1 and the pulley only turns when motion is communicated to it by a catgut from the flywheel behind it4 ,the back poppet and rest1 which last is shown separately1 slide on the rectangular bar2 the latter is about two inches wide1 and three eighths thick1 and is made with feet to screw to any convenient support4 ,this lathe is especially adapted for work of small size which can be centred at both ends1 and on which a carrier can be fixed to bear against the pin1 ,e1 of the pulley2 nevertheless it is even possible to use chucks1 if cast in metal with a pulley to each like ,g4 ,a spindle must in this case be made like ,h1 on which the chuck must be slipped1 and fixed by the nut in the hollow of the chuck4 ,although however this form of lathe is sometimes met with1 and may be used as a makeshift1 a small triangle bar or #c;in4 lathe of the usual form is far preferable4 ,illustration3 ,,fig4 #abc4 ,in centering a bar of iron in the lathe too much care cannot be exercised in causing it to run evenly4 ,the ends should be drilled1 first with a small1 and afterwards with a larger drill1 so that a countersunk hole may be obtained in order to keep the point of the lathe-centre from touching the bottom of the hole4 ,if this is not done the friction of the work upon its bearing will soon spoil the lathe-centre1 and the work itself will speedily get out of truth1 and it will not be possible to screw up the spindle of the back poppet so as to correct this4 ,of course in turning up very small work this drilling cannot be done4 ,a simple hole must then be made1 sufficient for the safe support of the work while being turned1 but even in this case the angle of the drill point should be less than that of the conical centre of the lathe1 the point of which will then run free4 ,to mark the true centres of a round bar of metal a punch has been devised like ,fig4 #abd4 ,this is figured in ,bergeron's work1 and is very serviceable4 ,to insure its working truly be careful that the bar of metal is filed flat on the ends1 and that the surface of the latter is at right angles to the length of the bar4 ,it is then only necessary to place the end of the piece in the conical part of the cup 7which will be best effected by fixing the bar in a vice7 and by raising the spring and letting it go sudden by a sufficient mark will be made to guide the point of the drill4 ,illustration3 ,,fig4 #abd ,the proper place at which to commence turning an iron bar is at one end1 the rest being placed so as to bring the tool just upon the line of centres2 if applied lower the tool would take too deep a hold1 and would either be broken or lift the bar out of the lathe1 damaging the centre points4 ,the ends of the bar should be squared up before the circumference is turned1 and on no account must a file be used after the turning tool has done its work4 ,it is only at the commencement before a cutting tool has been applied1 that an old file may be made use of to take off the scale and roughness left from the forging or casting4 ,brass may be attacked upon or just below the line of centres1 because the form of tool is such as cannot penetrate deeply4 ,this metal is perhaps easier in some respects to turn1 but the tool is apt to form undulations on its surface 7is apt to chatter74 ,this is due1 partly to the impossibility of obtaining continuous shavings1 and partly to the vibration of the tool1 and when once this has taken place there is a tendency to deepen these channels1 which makes it difficult to produce a plane and even surface4 ,if a rectangular tool is used in the position already shown and described under the head of tools for metal turning1 this chattering will be avoided4 ,if it takes place1 the undulations should be worked off by gentle usage of the angle of the tool1 the rest being placed close to the work1 and only a light cut taken4 ,with regard to the method of mounting a piece of brass in the lathe1 any convenient chuck may be used1 but sometimes the piece is short or irregular and requires to be bored out4 ,in this case use solder and firmly attach the piece to a face plate of brass4 ,the easiest way is to smear the two faces to be joined with sal-ammoniac made into a paste with water1 and laying a piece of tin-foil between the surfaces1 which must be quite clean and bright1 apply heat4 ,the tin will melt and a perfect union will be effected4 ,when the piece is finished it is re-heated and detached4 ,this may be considered a wrinkle worth knowing4 ,the flat flanges of brass spoken of under the head of chucks are just suited for this method of working1 and they are not damaged by the process1 as the solder can be wiped off quite clean when the chuck is made hot4 ,this is a good way to mount small cylinders of brass for model engines1 as they can be bored and turned on the outside at one operation with great ease and certainty4 ,if a piece is to be drilled or bored in the lathe1 the following is the arrangement to be adopted4 ,fig4 #abe1 ,a is the face plate1 ,b1 the piece to be drilled1 ,c the drill1 which is advanced by screwing up the point1 ,e1 of the back centre2 ,d is a hand vice or similar article to prevent the drill from revolving with the work4 ,if it is more convenient to fix the drill itself in a chuck1 the point of the back centre is to be removed1 and a flange of brass or iron substituted1 as ,a1 ,fig4 #abf4 ,if the drill is to penetrate quite through the work a piece of wood must be interposed between the latter and the flange to receive the point of the drill and protect it from injury4 ,the pressure should be so regulated as to be constant and equal without being excessive1 or the drill will be bent or broken4 ,boring is simply drilling on a larger scale1 and is of such general use as to require detailed notice4 ,in the first place there are several tools used for the purpose1 according to the size of the work4 ,the first is the cylinder bit1 ,fig4 #abg4 ,this is a most excellent tool1 as it will work very truly1 and can hardly get out of place if properly directed at starting4 ,the cutting part ,a is half a cylinder1 the centre being just left visible1 the end is not quite at right angles with the length of the tool1 but is sloped off a little and bevelled also slightly below4#g ,this forms the cutting edge4 ,the other end of the tool has a central hole1 drilled to receive the point of the back centre by which it is kept to its work4 ,to use this tool1 let the piece to be drilled be placed in a chuck1 and a recess turned in it of the same diameter as the cylinder bit1 the latter is then placed in this recess ,b1 and when screwed up it cannot possibly rise or shift its position2 a hand-vice or spanner is then fixed as shown in ,fig4 #abe1 and the lathe put in slow motion1 oil or soap and water being freely used to lubricate the tool4 ,either a solid piece of metal1 or a hollow casting can be thus bored4 #g ,to an angle of #c4 ,see ,appendix4 ,illustration3 ,,fig4 #abe4 ,illustration3 ,,fig4 #abf4 ,illustration3 ,,fig4 #abg4 ,these cylinder bits can be had of all sizes1 from one-eighth of an inch upwards4 ,pipe stems are bored with the smallest of these tools4 ,for this purpose they are made of round steel wire1 which is sometimes merely flattened with a hammer at one end to spread and enlarge it1 this part being afterwards rounded on the underside with a file1 and with the same tool finished on the upper flat face4 ,these slender drills require to be delicately used1 and are conveniently held in a pin vice or pair of pin pliers1 the handle of which being hollow1 allows the greater part of the drill shank to lie within it1 a small part only being drawn out at a time for use2 thus the drill will be kept from bending1 and will work quickly and well4 ,of recent inventions in the matter of drills1 the most important is the ,morse ,american twist drills sold1 in sets1 at #cjs4 on a neat stand with a self-centering chuck1 complete4 ,the form is that of a cylinder with spiral grooves cut round it of extended pitch4 ,the cutting edge is as difficult to draw as it is to describe1 and must be seen to be understood4 ,it is chiefly formed by the meeting of the spiral grooves and the solid end1 the latter forming a blunt angular point rendered cutting by the edge of the grooves4 ,they should have a place in every workshop4 ,the next tool to be described is also much used1 especially in agricultural implement manufactories1 for boring out the brasses1 or bearings4 ,it is called a rose bit1 or grinder1 and is shown in ,fig4 #abh ,a and ,b4 ,in this case also a recess is cut in the work as a guide1 and as the tool fills up the whole interior as it proceeds1 no change of position can occur4 ,the rose bit is used as shown in #abe4 ,a bit of this pattern is very useful for brass work of all kinds1 such as the cylinders of small engines1 bosses of wheels1 bearings and collars1 and one of these tools of the exact size for hollowing out the sockets of brass chucks1 previously to their being tapped1 will be found serviceable4 ,the third kind of boring tool is made with movable cutters1 which can be removed at pleasure1 to be sharpened or replaced by more convenient ones4 ,the simplest consists of a cutter bar1 ,a1 ,fig4 #abi1 with a slot in it to hold the tool1 which is fixed by driving a wedge at the back of it4 ,the tool here shown has two cutting edges1 b and c which should be shaped according to the principles already enunciated respecting hand tools for iron and brass4 ,the cutter bar is usually fixed between the lathe centres1 and turned by a driver chuck and carrier1 while the cylinder to be bored is clamped to the slide rest1 and thereby advanced against the cutting edge4 ,this form is chiefly used upon work that has been cast hollow1 or drilled4 ,illustration3 ,,fig4 #abh4 ,illustration3 ,,fig4 #abi4 ,fig4 #acj is another form of boring tool for large and heavy work4 ,a boss1 ,a1 is fixed to the cutter bar1 having a series of dovetailed grooves1 or slots1 on its surface1 in which cutters are fixed by wedges4 ,in this and every similar form1 it is expedient always to complete the circle1 or1 at any rate1 two-thirds or three-quarters of it1 by driving in blocks of wood in the slots not occupied by the cutters4 ,this preserves the concentricity of the tool4 ,one edge of these movable cutters should be radial to the centre of the bar1 or boss1 the other rather less than a right angle1 which will ensure a good cutting edge4 ,the best lubricant is oil for the first cut1 and soap and water1 or pure water1 for the finishing cut4 ,the surface will thus be left bright4 ,it is not well to finish with emery any collar in which an axle is to work 7as the collar in which the mandrel of the lathe runs74 ,this substance imbeds itself in the pores of the metal1 and by forming a grinding surface1 considerably increases the friction and wear and tear of the parts4#h ,although boring and drilling are capable of being done in the lathe1 a far superior plan is to employ an upright boring apparatus1 as is now generally used in making steam cylinders4 ,the work is not then suspended between two points1 or carried on the slide rest1 but takes up a firm bearing on a fixed support1 and the boring tool descends by a pressure screw1 or self-adjusting contrivance1 as the work proceeds4 #h ,oilstone powder may be substituted1 especially for the best brass work4 ,illustration3 ,,fig4 #acj4 ,we have spoken of the slow motion as necessary for turning metal work4 ,this is represented in ,fig4 #aca ,a ,b ,c ,d4 ,the first is a plan seen from above4 ,the poppet is cast double like ,f1 so as to afford a bearing for the mandrel1 and a second for the back spindle seen at ,a4 ,this back spindle1 it will be observed1 passes through its two collars or bearings1 and can slide freely in them from side to side4 ,this can1 however1 be prevented by dropping a pin through a hole in the top of the poppet1 which falls into a semicircular groove in the spindle4 ,the pulley is securely attached to a small cog wheel1 and can be firmly united to a larger one1 as seen at ,a#b1 and separately at ,c and ,d4 ,this pulley and small cog wheel run loosely on the mandrel1 and do not revolve with it until clamped to the wheel1 ,c1 which is itself keyed to the mandrel4 ,suppose them to be thus free to revolve1 and the wheels in position shown in the plan1 ,a4 ,on putting the fly wheel in motion1 the pulley will revolve on the mandrel1 carrying with it the small cog wheel1 which in turn will act on the large wheel on the back spindle4 ,the small cog wheel on the latter will thus put in motion the large one geared with it1 the which being keyed to the mandrel1 will put the latter in motion4 ,there are many ways of clamping the pulley to the large cog wheel1 perhaps the following is as good as any4 ,it must be so clamped for wood turning when the back spindle is to be slipped on one side out of gear4 ,illustration3 ,,fig4 #aca4 ,in the face of the pulley1 which is concave1 is a piece of brass flush with the rim1 and which forms a dovetailed groove1 into which the head of a clamping screw1 ,e1 fits4 ,this screw projects through a slot in the wheel ,d4 ,when it is required to fix the pulley1 this screw is slid up towards the rim till the head rests in the dovetailed projection1 and it is clamped in that position by a nut4 ,when it is desired to put the back action into gear1 this nut is loosened1 the screw-bolt dropped towards the axle 7thus freeing the head from the dovetail71 and again fixed by the nut4 ,the wheel and pulley are thus independent of each other1 the back spindle is slipped sideways into gear1 and held by the pin1 and the slow motion will be obtained4 ,there is one fault in the arrangement of the back geared lathe that with amateurs in a private house is especially disagreeable1 and it is questionable whether in large machinery establishments it might not with great advantage be corrected4 ,in the action of toothed wheels1 nuts and screws1 and similar gearing1 there occurs what is called back lash4 ,if1 for instance1 the tool holder of a slide rest is advanced1 and then the action is to be reversed1 the movement of the nut and tool holder does not commence simultaneously with the movement of the screw4 ,this is due to the play1 or necessary looseness of the working parts1 the pressure coming on one side of the thread when the screw is turned in one direction1 and on the contrary side when the motion is reversed4 ,in toothed wheels a similar defect exists1 and gives rise to that disagreeable and ceaseless noise which assails the ear on entering a building where machinery is in motion4 ,this may be avoided by the use of frictional gearing1 a simple but excellent mechanical contrivance which deserves far more extensive notice than it has yet received4 ,it is the invention of a ,mr4 ,robertson1 and is patented4 ,a lathe fitted with it would be almost noiseless1 and would work with a delicious smoothness1 very conducive to the comfort of the workman4 ,this gearing1 represented in ,fig4 #acb1 is merely the substitution of ,v shaped or semicircular grooves for cogs1 the former running round the periphery of the wheel like the grooves in an ordinary lathe pulley4 ,in this method of gearing1 it would be necessary to move the back spindle to-and-fro1 the usual horizontal movement not being possible4 ,this is easily effected by a screw or a cam1 either of which might be made to act on the frame which carries the back spindle1 and which may then work on a centre1 as ,fig4 #acc1 where ,a is the poppet1 ,b1 the support of the spindle1 ,d1 a cam2 when the handle of the latter is raised1 the standard1 ,b1 is allowed to fall back out of gear into the position shown by the dotted line1 ,c4 ,a screw movement would have the advantage of enabling the workman to regulate with greater precision the pressure of the friction pulleys against each other4 ,the drawing shows the grooves of these pulleys larger and deeper than usually made4 ,they are generally rather shallow and numerous1 and it is astonishing with what firm hold they grip each other without that violent pressure which it might be imagined would be necessary to prevent slipping when in use4 ,illustration3 ,,fig4 #acb4 ,illustration3 ,,fig4 #acc4 ,the ordinary slide rest for hand lathes is made as follows3--,that for ornamental turning will have a separate notice4 ,fig4 #acd1 shows the slide rest viewed from above1 and it is evident if the tool is clamped to the holder ,f on the top plate1 it can be advanced from end to end of the top slide ,b1 and also 7with the upper frame itself7 along the lower frame ,a1 ,a1 these movements being at right angles the one to the other4 ,for parallel work this is sufficient4 ,in this compound rest a third motion is arranged for turning cones or taper plugs like those of stop cocks1 taps for screw plates and such like articles4 ,for this purpose the upper frame is cast like ,fig4 #ace1 with a flat surface1 but with two ribs underneath1 uniting the frame to a circular plate with two concentric slots in it4 ,this plate revolves on the plate ,g ,g1 turning on a central pin1 and it can be clamped by the two screws which pass through the slots into the plate in any desired position2 once clamped at the required angle a piece of metal can be bored with a conical hole and a plug turned to fit it without possibility of failure4 ,the details of construction allow of considerable variety1 and different makers keep to their respective patterns2 the main desideratum is strength and solidity1 combined with accurate adjustment of the moving parts4 ,the ,v's1 underneath the frames1 and the edges of the latter1 must fit1 so as not to be tighter in one place than another1 and the upper and lower frames must cross each other accurately at right angles4 ,it is likewise essential that the tool traverse the work in a perfectly horizontal line4 ,every part must1 therefore1 be accurately made by means of the lathe and planing machine1 and the whole carefully put together4 ,notwithstanding the above desiderata1 a slide rest is not necessarily beyond the skill of the amateur4 ,we have1 indeed1 seen one thus made quite equal to the work of a professed mechanic1 though the file and scraper had to take the place of the planing machine4 ,the rough castings can be bought for about half-a-crown1 suitable for a five-inch centre lathe1 and it would be much better to try and fit up a set of these castings than to attempt such a substitute as a wooden slide rest4 ,the latter has nevertheless been made1 and we remember seeing one of mahogany edged with brass1 the work of a cabinet maker1 which did good service in turning and ornamenting wood4#i ,this1 however1 was upwards of twenty years ago1 since which time the facilities for obtaining slide rests of metal1 properly constructed1 have materially increased4 ,as the dovetailed edges of the slides wear away by use1 it is necessary to provide means for tightening up the ,v-pieces4 ,this is shown in ,fig4 #acf4 ,the holes in the ,v-pieces through which the top screws pass are not round1 but oval1 so as to admit of lateral movement4 #i ,in the ,paris ,exhibition of this year 7#ahfg7 are some slide-rests made of hardwood and metal4 ,illustration3 ,,fig4 #acd4 ,illustration3 ,,fig4 #ace4 ,illustration3 ,,fig4 #acf ,two large headed screws1 ,e ,e1 are tapped into the place on which the ,v-pieces rest1 and when these are screwed up1 their heads 7which are sunk for the purpose in two recesses in the lower plate7 press against the ,v-pieces1 driving them closer to the dovetailed slide4 ,when thus adjusted the top screws are made use of to fix the strips c1 c4 ,by this method the slides can be adjusted to work with the utmost ease and accuracy1 without shake or side play4 ,the edge of the circular plate and the heads of the leading screws are very frequently marked in graduated divisions1 so that the advance of the tool or the angle to be made with the work by the tool can be accurately measured and preserved4 ,there should at any rate be a mark on the circular plate to show when the rest is set for parallel work4 ,there are several patterns of tool holder1 of which the forms shewn are convenient for light work4 ,the one shown in #ach #aci on the rest is somewhat different4 ,the plate ,f1 ,fig4 #acd1 is cast with a boss and socket1 like that of an ordinary rest4 ,in this socket the tool holder fits1 and can be not only turned round so as to set the tool at any angle1 but also slightly adjusted in height1 which is a great advantage4 ,the tool is clamped by a single screw as shown in the sketch4 ,the drawback to this form1 and that on the rest1 is this single screw1 which will indeed hold the tool when the work is easy1 but will not always retain it with sufficient firmness when the work is rough1 or of tolerable size4 ,in large workshops one usually meets with the holder represented in ,fig4 #adj4 ,a plate1 ,a1 with central block ,b1 and slide ,c1 are in one casting4 ,through ,a pass eight screws4 ,the tool lies on either side of the central square block and is clamped with three screws1 it has thus a fair bearing on two sides1 and the screws form a third above1 so that accidental shifting of the tool during the progress of the work is hardly possible4 ,the tool holder of ,professor ,willis1 which is described in the ,appendix1 is perhaps the best of all at present in use4 ,it holds the tool firmly at any desired angle4 ,illustration3 ,,fig4 #adj4 ,illustration3 ,,fig4 #ach4 ,illustration3 ,,fig4 #aci4 ,it is quite possible that the novice who has seen mere boys working with slide rests at manufactories will be disappointed at his own first attempts to use this piece of machinery4 ,all the difficulty lies in the shape and set of the tool4 ,when turning metal with hand-tools it is easy to feel one's way4 ,if the cut is not satisfactory1 the hand at once modifies the angle of the tool1 and regulates its direction to a nicety1 but the slide rest cannot thus adapt itself to its work4 ,it must be set with its slides in position1 and the tool once fixed must pursue its own course4 ,hence it requires a very accurate knowledge of the nature of cutting tools1 such as we have given in the ,appendix to this work4 ,if the tool is well placed upon the axis of the work for iron1 a little below it for brass--it will cut cleanly and easily1 without rubbing or jarring1 both of which are proofs of either a wrong angle of edge1 or a wrong form of tool4 ,the work should proceed with as much apparent ease as if the metal were an apple1 and the shaving should curl off like its peel4 ,moreover1 this case is not merely apparent1 it is perfectly easy to cut iron1 and the strain on the tool1 whether held by the hand or by slide rest1 is comparatively slight1 if the tool is properly made and held4 ,fig4 #ada is quite the best form of tool for surfacing cylinders with the slide rest4 ,it is to be so placed that both edges are made to cut near the point2 hence the crank should slightly curve away to the left4 ,it is not possible to cut metal quickly1 be content with fine clean shavings curling off freely4 ,you will soon see whether you can take a deeper cut with safety4 ,the tool here sketched is not at all likely to dig in and hitch in the work2 if it is not properly placed it will spring and jump1 or its side will rub against it1 and no cut will be made4 ,to describe the exact position is very difficult1 but the principle once grasped1 little difficulty should be experienced in making and setting to work any tool1 whether for inside or outside work4 ,the rule of thumb was all well enough in olden days and in the infancy of the art of metal working1 but it is time to discard it2 to master and man it is equally advantageous to do so4 ,indeed1 in some of our leading firms1 the old system of follow-my-leader1 when the leader was as ignorant of his work as the follower1 is waning1 and the how is now1 as it ought to be1 coupled with the reason why4 ,one of the best papers ever written on this subject is to be found in ,weale's series1 ,mechanism and ,construction of ,machines1 by ,t4 ,baker1 and ,tools and ,machines1 by ,j4 ,nasmyth1 #bs4 #f;d4 ,the latter part is that specially referred to1 and is well worth the whole price of the work4 ,the remarks1 however1 of that eminent mechanic are embodied in the paper in the ,appendix1 and therefore1 after the reader has studied the latter1 he should make trial for himself of the principles laid down4 ,expend a quarter or a half an hour experimenting thus1 with keen and obtuse tools1 held at divers angles1 and you will see and understand what is meant by setting a slide rest1 or hand tool to cut metal as it ought to do4 ,illustration3 ,fig4 #ada is too much cranked2 half the length of the hanging part would amply suffice4 ,supposing the tool fixed in the tool holder in the position indicated1 and just overlapping the circumference at one end 7the right74 ,take hold of the handles1 one in each hand1 and with that which advances the tool from end to end of the bar try very carefully whether the tool will cut cleanly by making a turn or two while the lathe is in slow motion4 ,if the tool bites too deeply1 turn the other handle and ease it4 ,if you still find the tool sticking into or scraping the work1 instead of bringing off a fine shaving1 look well to its position1 and observe whether the edge is well placed on the axis of the piece4 ,if it has been hitching in the work it is probably too low1 if rubbing it1 too high1 and touches at some point below its edge4 ,it is presupposed1 of course1 that the tool is made correctly as to angle of cutting edge4 ,do not lower the point by packing the end of the shank2 pack the whole length or none4 ,it is astonishing what a great difference is made to the cutting power of a tool by slight adjustments of this kind1 and how smoothly a tool will work with proper attention to these details1 which would otherwise be probably cast aside as unfit for the work4 ,hence the greater ease in managing a hand-tool4 ,the hand feels the error1 and at once1 if experienced1 corrects it by an almost imperceptible movement--slightly raising or depressing the handle or gently varying the angle sideways on the rest4 ,when once the tool is found to cut as it ought to do1 nothing remains but to turn the handle in the right hand1 and thus cause the tool to progress steadily along the work from end to end4 ,then free it by a half turn of the other handle1 reverse the movement until the tool has arrived at its old place1 and having slightly advanced it to take a fresh bite1 repeat the process until the whole bar is reduced to the required size4 ,if the piece is slender and bends away from the tool1 add to the slide rest a support2 let it be fixed opposite to the tool1 and it will keep the work steadily up against the cutting edge4 ,it can be fixed 7if a hole is made for the purpose7 anywhere about the slide which traverses in the direction of the length of the work4 ,it is well to drill and tap a few holes about the slide rest1 and some along the side of the bed of the lathe4 ,these will be found very useful at various times for fixing apparatus4 ,for1 be it observed1 7and we shall recur to this with some practical hints by and by7 the lathe may and ought to do many kinds of work beyond ordinary turning4 ,it may become a machine for planing1 slotting1 drilling1 wheel cutting1 c41 and is to be pressed into the service of the jack-of-all-trades1 without compunction4 ,when ordering a slide rest let steel screws and nuts be specified1 and gun metal ,v-pieces1 and let the parts be strongly made 7too strong for the supposed work72 for the latter may unexpectedly turn out to be sometimes rather heavy4 ,we have found the top plate of a #c;in4 slide-rest so weak that when the tool was clamped on the top of it1 by the screw of the tool holder1 the slide itself became jammed2 a defect quite beyond remedy1 except by the substitution of a new and stiffer plate4 ,the same advice may be given respecting the tools4 ,let these also be strong2 neat and pretty tools are all very well1 but you seldom see them in a workshop2 you don't require pretty tools1 but good and serviceable ones4 ,nevertheless1 let the material be of the best quality possible2 and that you may not be ever at a loss1 you should learn to make tools yourself4 ,procure some small square and round steel bars2 save up as directed your old files1 and you need but heat them red hot 7not on any account white hot71 and with hammer and file shape them to your mind4 ,then temper to a deep straw colour1 and after being accurately ground and finished on the stone1 they will be fit to use upon any metal4 ,the form of tool given as the best for slide rest work may be exchanged1 when the bar is nearly turned1 to the required size1 for a fresh one1 keen1 sharp1 and of an almost flat edge instead of point4 ,a tool1 of which the edge is a segment of a very large circle1 will serve the best as a finishing tool1 just to take off the lines left by the pointed tool4 ,with regard to lubricating the work1 we may observe that the chief object is to prevent the point or edge of the tool from heating and losing temper2 oil1 water1 or soap and water will therefore answer1 but it is a curious fact that oil will not produce so polished a surface as water will4 ,we should advise in all cases soap and water4 ,soft soap is best1 boiled in water1 and allowed to cool4 ,the drills with which the huge armour plates of ships six inches thick are drilled are thus lubricated1 and instead of throwing out dust in a wet state as usual1 these large drills fairly turn out curled shavings similar to those produced by the planing tool4 ,it is by no means a bad plan to lay the shank of the tool which falls upon the top plate of the rest1 upon a piece of leather1 wood1 or sheet lead4 ,the surface of the iron1 when planed and finished1 is often too smooth1 and the tool will sometimes slip from this cause1 unless screwed unduly tight1 to the detriment of the rest4 ,by the above plan this annoyance will cease at once4 ,we will now say a word about hollowed work4 ,finishing a chuck will serve our purpose1 and here be it advised not to go to much expense about chucks--get those which must be of brass in the rough1 and practice metal turning by finishing them yourself4 ,if no slide rest is available do it by hand4 ,however1 we are supposing the slide rest to have been procured1 and may therefore proceed to use it4 ,first you must drill the back part of your chuck as directed in a previous chapter4 ,the drill is to be the size of the diameter of the hollows in the mandrel screw1 that is1 smaller by the depth of a thread1 than the full size of the nose4 ,having drilled it1 proceed with the most tapering of your taps1 which we suppose to be provided to form the internal thread 7external if your mandrel has female screw1 in which case1 instead of a drilled hole1 the chuck will have a projection to be turned truly cylindrical1 and a screw cut outside with stock and dies or chasing tool74 ,follow up with the intermediate and finish with the plug tap4 ,if you were careful to square up the shoulder1 the drill having been likewise placed perpendicularly to the face of the chuck1 the latter will fit truly up to the collar or shoulder on the mandrel4 ,if not1 you must go to work again1 and square up the back of the chuck till a good fit is produced4 ,now1 if you have a compound slide rest--that is1 one in which the slides turn on a centre pin--you can loosen the screws and turn it a quarter of a circle4 ,if not1 you simply put the tool into the holder1 at right angles to its former position1 so that the movement of that slide which is parallel to the lathe bed will become that requisite to advance the tool into the hollow of the chuck4 ,whichever way you set to work put in a side tool1 like ,fig4 #adb1 and1 as it is a brass chuck1 remember that the bevel underneath is to be very slight4 ,introduce the tool so as to take a light cut at first1 until the roughness is taken off1 after which you may cause it to bite more freely4 ,repeat this until the chuck is sufficiently hollowed out1 when you may substitute a similar shaped tool1 but with a flat or slightly rounded edge1 to take off the marks left by the point tool4 ,to finish the bottom of the inside you will require a tool which cuts on the end1 but it should not have a perfectly flat end--at any rate1 not until1 by means of a pointed or small round-ended tool1 you have cut away the roughness left from the process of casting4 ,this has always in its interstices a number of grains of sand fused1 and very hard and detrimental to cutting edges of all kinds4 ,the point tools dig these out very effectually1 and should always precede those of other forms4 ,illustration3 ,,fig4 #adb4 ,the outside must be turned in a similar manner1 and a hole drilled to receive a pointed bar or wrench1 for the purpose of unscrewing it when screwed up tightly4 ,to turn up a face plate of iron or brass proceed in a similar way1 but commence from the centre with a point tool4 ,this tool is the best for taking off the rough outside of hard wood1 instead of the gouge1 as well as for removing the roughness of a fresh casting4 ,it is absolutely necessary that the faces of these flat chucks1 or surface chucks1 be truly at right angles with the mandrel2 hence it is very difficult to turn and finish them by hand4 ,we may here also state the necessity of knowing when the slides of the rest are at right angles to each other1 without which no work can be turned correctly4 ,it is necessary to ascertain this by help of a small steel square4 ,once fixed truly1 it is only necessary to make a mark on the quadrant 7which should be marked in true degrees71 by which the same position can be found again at any time4 ,we have spoken here of the quadrant--we mean the arc1 or arcs with slot--allowing the circular movement of the compound slide rest4 ,the chief use of these is to enable the workman to turn true cones instead of cylinders1 which latter will only be produced when one slide is parallel to the lathe bed4 ,such is the common use of the slide rest2 and it will be evident from these few remarks that there is an infinity of work1 not only produced with ease by its aid1 but which cannot1 even with expenditure of time and labour1 be produced without it2 hence we advise this to be the chief ambition of the tyro after he has mastered the difficulties of ordinary hand turning 7and not before74 ,the cost of a fair one for #e-;in4 lathe will be #e1 or thereabout4 ,at ,munro's1 #g or #h2 at ,holtzapffel's1 #aj or #ab4 ,both the latter are of course perfect4 ,we have directed to tap the chuck where it is to be screwed to the mandrel with a set of three taps1 or to cut it with stock and dies if an outside thread is required4 ,in both cases more true and satisfactory work may be produced by the chasing tool4 ,we speak of the latter as used by hand2 an account of cutting the threads by help of the slide rest we reserve for the present4 ,mount the work in any convenient way1 either driving it into a wooden chuck1 or by clamping it to the face plate if you have one4 ,now in this way you have advantages4 ,in the first place you need not have a drill the exact size1 though it is convenient to have such a one1 and also a cylinder bit4 ,you can drill and enlarge the hole by the slide rest tools1 and you can also with the slide rest ensure the perpendicular position of the hole with respect to the end4 ,thus it is sure to fit up close and snug to the shoulder of the mandrel4 ,when bored thus it will be in position for chasing4 ,it is not difficult to chase a thread in brass1 as it does not chip away like wood1 but cuts clean and sharp4 ,follow the directions already given and you will succeed in a few turns in getting the tool to run4 ,then let it have its own way2 hold it lightly1 but steadily1 and do not force it either to cut too deeply1 or to advance too quickly2 it will run along of itself after the faintest thread is cut or scratched1 and the lathe can be worked by means of the treadle all the time as soon as you have attained the knack of dropping the chaser into its place at the commencement of its cut1 and suddenly withdrawing it when it has reached the bottom of the hole4 ,a chuck thus turned and screwed entirely in the lathe is sure to prove a good fit1 and there can be no better practice than to cut screws in all your brass and boxwood chucks in this way4 ,a very good chuck to hold flat plates of brass was invented by a ,mr4 ,wilcox1 of ,bishop's ,stortford1 some years ago--an amateur of rare ingenuity and mechanical knowledge1 and who made all his own apparatus for plain and eccentric turning4 ,the chuck1 ,fig4 #adc1 as described by him in some unpublished manuscript1 is made of boxwood1 or may be of metal4 ,it is a plain disc or surface chuck with three slots ,a ,b ,c4 and a steel centre4 ,this last must penetrate rather deeply into the wood of the chuck1 but is only kept up so as to project from the surface by a spiral spring below it4 ,hence1 when pressure is made upon its point by the application of the object to be turned1 the pin recedes into the body of the chuck1 suffering the work to lie flat on its surface4 ,in the three slots are three screws1 with nuts at the back of the chuck the screws pass through two pieces of brass1 forming a pair of jaws1 one of which is shown separately4 ,illustration3 ,,fig3 #adc4 ,fig4 #adc shows the chuck complete4 ,suppose we have to face up a round disc in its central part1 or to perform any surface work in which the jaws will not be in the way of the tool1 the centre of the plate is marked at the back of it1 and this mark laid on the central pin4 ,the work can be clamped down by the three jaws1 and the necessary work may be done4 ,now so far the chuck is but a simple affair1 and the receding pin does not show itself to such great advantage2 we will therefore suppose a plate is to be drilled at several spots2 let these be marked at the back by a centre punch4 ,it is now only necessary to bring these marks in turn upon the central point1 and clamp the plate in position4 ,bring the point of the drill against the work and keep it up to cut by the back poppet screw4 ,in the same way eccentric work or any operation may be done to such a plate1 with the certainty that the point to be thus worked upon is precisely central with the axis of the pulley1 or mandrel4 ,many similar applications of this chuck will present themselves to the reader upon due consideration4 ,we present the chuck in this place because we have had occasion to speak of drilling as connected with the slide rest1 and there are many pieces of work that could not otherwise be conveniently held in the desired position4#aj #aj ,the ,,ms4 book containing the above was kindly lent to the author of the present work by ,mr4 ,hoblyn1 of ,bishop's ,stortford1 who is the inventor of a new form of slide rest1 which will be introduced in a later page4 ,the chuck in question is1 however1 commonly attached to the watchmakers' lathes of the present day1 and therefore may not1 as the writer supposed1 be actually the invention of the late ,mr4 ,wilcox4 ,,overhead ,,apparatus4 ,it now becomes necessary to speak of another addition to the lathe1 by means of which the use of the slide rest is considerably extended4 ,we mean the overhead motion4 ,of this there are several patterns1 and we have sketched three of these4 ,as to their respective merits we can hardly venture to speak4 ,they all answer equally well the purpose for which they have been designed1 and the turner must select according to his fancy1 or1 if he please1 design a better for himself4 ,a1 ,fig4 #add1 represents the lathe bed4 ,from the left-hand standard rises a round iron rod1 not less than one inch in diameter4 ,this is not generally fixed1 but is attached to the standard by two staples1 a1 b1 which hold it securely in an upright position1 but allow it to turn with its projecting bar ,f1 ,f1 after the manner of a crane4 ,it may thus be turned back1 out of the way1 or brought into any desired position4 ,the part ,f1 ,f is made to slide up and down on the part ,b1 and is fixed by a clamping screw ,d4 ,thus1 if the cord should break and require to be shortened1 the arm can be brought nearer to the bed of the lathe4 ,upon ,f1 ,f slide two rings1 or rather short pieces of tube1 from which depend two ,india rubber springs 7door springs71 ,e1 ,e1 now procurable at any ironmonger's at one shilling each4 ,from these hang double pulleys1 or better still two single ones4 ,these pulleys1 with their attachments1 are adjustable at any position on the arm ,f1 ,f1 which may be round or square4 ,if considered desirable1 a second standard can be added1 so as to uphold both ends of this bar2 but it is hardly necessary1 as the latter is seldom required of greater length than half that of this lathe-bed4 ,it is evident that the above addition to the lathe can be made complete for a few shillings4 ,the following are more expensive1 but more general1 the writer having devised the above to suit his own fancy1 and for his own use4 ,in ,fig4 #ade ,a represents the standard as before1 the top of which is forked1 as shown at ,e1 and sustains the ring1 free to revolve in its arms1 as seen in the sketch4 ,through this passes a bar1 ,b1 ,b1 with a heavy ball ,c cast on its end to act as a counterbalance to the longer arm and its connections1 and to keep the cord stretched4 ,by sliding this bar either way through the ring which supports it1 the tension of the cord can be increased or lessened4#aa ,when in position it must be very securely fixed by the screw ,t1 which should not simply press against it1 but enter one of a row of depressions made for the purpose4 ,the pulleys ,c1 ,d are double1 as in the previous plan of overhead1 and are likewise adjustable at any position on the bar ,b1 ,b4 ,the only drawback to this pattern is the danger of the heavy ball slipping out and falling4 ,we prefer to hang a weight from the end of the lever1 as shown by the dotted line4 ,this may be within a few inches of the floor1 and if it should fall no harm can ensue4 ,the third pattern1 ,fig4 #adf1 is the most expensive1 but although it is of a more finished appearance1 and wears an aspect more stiff and stable1 it is not practically any better than the last4 ,from a standard ,a1 with overhanging bar ,f1 ,f1 is suspended a frame ,h1 by means of two coiled springs in brass boxes ,b1 ,b1 which keeps up the necessary tension on the cord1 or rather cords1 for in this case two are needed--one from the flywheel to the small pulley1 and a second from the roller to the slide rest4 #aa ,sometimes the bar is merely hung on pivots1 and the weight is made to slide upon it4 ,illustration3 ,,fig4 #add4 ,illustration3 ,,fig4 #ade4 ,illustration3 ,,fig4 #adf4 ,illustration3 ,,fig4 #ade4 ,illustration3 ,,fig4 #adc ,this roller1 which may be grooved or plain1 may be replaced by a second small pulley1 which is capable of being slid along the round bar which forms its axle and turns with it between the centre screws4 ,in this case the bar is made with a groove or channel along its length1 ,fig4 #adg1 and a pin projecting from the central hole in the pulley enters this groove4 ,thus the two will turn together1 and at the same time the position of the pulley is adjustable at pleasure4 ,the tension of the springs ,b1 ,b1 is increased or lessened by a turn or two of the nuts ,c1 ,c1 just in the same manner as the spring of the safety valve is adjusted on the boiler of a locomotive4#ab ,the application of the overhead motion is plainly shown in ,figs4 #adc and #add4 ,the work is fixed in the lathe1 and the mandrel kept stationary4 ,the cord passes to the overhead directly from the fly wheel1 and thence to a pulley on the screw of the slide rest1 as in #adc1 to a drill1 as in #add1 or to any other apparatus at pleasure4 ,to fit the work in the lathe in such a manner as to enable any point in the face or side to be operated upon1 a division plate and index are required4 ,the first is a round plate of brass or gun metal1 #a-afth of an inch thick1 drilled with holes in concentric circles4 ,the index is a steel spring with a projecting point1 which1 entering any one of the holes1 retains the plate1 and with it the pulley1 on the face of which it is fixed immovable4 ,there are generally four circles of holes1 the number in each selected with reference to its divisibility by the greatest possible number of divisions--thus #cfj1 which is usually on the outside or largest circle1 can be divided without a remainder by #b1 #c1 #d1 #e1 #f1 #h1 or #i--add is a good number for the second circle1 being divisible by #b1 #c1 #d1 #f1 #h1 #i4 ,the other two may be #aab and #if4 ,the uses of the division plate are many4 ,eccentric cutting and drilling could not be done without its aid1 and wheel cutting for clocks1 or for making cycloidal and other chucks1 is entirely dependent on this contrivance4 #ab ,the frontispiece shows another superior form of overhead1 with balance-weights hanging close to the ground behind the lathe4 ,illustration3 ,,fig4 #adg4 ,the division plate and index are shown in ,figs4 #adg1 ,a1 ,b1 ,c4 ,the part ,b is a knob with a round hole through it1 to take the tail of the spring ,c4 ,this is shown again at ,c on a larger scale1 to bring to view a slot which allows of some slight adjustment of the point1 to suit the different-sized circles4 ,the milled-headed screw clamps the point at any desired part of this slot4 ,when not in use1 the spring is drawn back so as to release it from the division plate1 and turned down in the position shown by the dotted line4 ,the overhead apparatus is applicable not only to revolving cutters in the slide rest1 but to other contrivances available where the latter is not possessed4 ,there are many cases in which the back poppet may be brought into use to hold revolving drills1 or stationary tools1 if the resistance to their action is not too great4 ,the only damage that can well happen in this method is to the pin working in the slot on the outside of the spindle4 ,if this is of steel and tolerably stout and strong 7being very short it cannot be subject to any very injurious strain71 no harm is likely to result4 ,with this it is possible to drill very neatly1 and also to do a little eccentric cutter work1 under certain conditions to be described4 ,screwing1 or rather chasing1 may likewise be done very passably4 ,we do not1 of course1 advise this course when the more perfect slide rest is at hand1 but there are many who are obliged to put up with all sorts of homemade contrivances1 and to press into service for divers operations apparatus and tools not precisely meant to be thus used1 and it is as well to learn how to act under an emergency1 even if the practice is not intended to be carried out generally4 ,the drill stock is shown in ,fig4 #adh1 in which the screw ,a fits into the spindle of the back poppet4 ,if the hole in the latter is conical instead of cut with a screw thread1 the drill must be made accordingly4 ,illustration3 ,,fig4 #adh4 ,the pulley of brass has a hole drilled through it1 and the screw is also drilled1 the hole in the latter being rather larger than that in the pulley 7which is tapped74 ,the steel pin ,h1 shown white in the sectional drawing1 passes truly through the centre of the screw in which it revolves1 and is screwed into the pulley4 ,the socket of steel to hold the drill is then screwed or soldered into the opposite face of the pulley4 ,the black part shows a flange on the screw which abuts against the cylinder of the poppet into which it is screwed4 ,thus the pulley1 being attached to the cord from the overhead apparatus1 is free to revolve upon the steel pin with great rapidity1 and will carry round any drills or cutters placed in the socket ,b4 ,the simple straight drill being thus worked and advanced by the leading screw of the poppet1 will suffice for holes in any work held on the mandrel4 ,on page #cce1 vol4 ii41 of the ,english ,mechanic1 this method is mentioned1 and also a similar pattern of slide tool to be used for boring1 being1 in fact1 the head and spindle of the back poppet1 but instead of the standard and sole1 a pin1 like that of a ,t1 to fit the socket of the rest4 ,this has the advantage of the back poppet1 but must be made on purpose1 and if any special slide tool is added1 a proper slide rest is by far the best4 ,our present purpose is to describe the use of the back poppet as a substitute for a better tool4 ,with the following modification of the eccentric cutter1 a fair amount of good ornamental work may be done4 ,fig4 #adi represents the back poppet with the apparatus in position4 ,the various parts are shown separately in ,a1 ,b1 ,c1 ,d4 ,a is a small frame1 two or three inches long1 and #c_/d to #a inch wide1 cast in iron1 with a circular piece at the back1 #a-a_/b or #b inches diameter4 ,this circular piece is to be accurately divided on the edge with any even number1 which is divisible as above explained4 ,this is turned and drilled through the centre4 ,b is a flange-shaped piece to screw to the poppet as before1 and this is also accurately drilled1 and the two are attached by a central steel pin1 so that the two flanges can turn face to face1 the outer one with frame revolving against the other4 ,the pin must be put in its place in ,b1 and turned at the same time as the face of ,b1 that it may be truly central4 ,the divisions on the edge of the outer flange are to be drilled like the division plate of the lathe1 or cut into cogs1 and in either case can be held at any point by a spring detent or index attached4 ,c shows the front of the frame1 with a screw down its centre and traversing slide f4 ,the head of this screw is divided1 and a small brass index marks its position2 one side of the frame may likewise be divided4 ,the small brass pulley and drill socket are fixed to revolve in the traversing nut or slide f1 as shown in a side view at ,d4 ,drills of all shapes1 as ,e #a1 #b1 #c1 #d1 may be fixed in the socket at pleasure4 ,illustration3 ,e ,illustration3 ,,fig4 #adi4 ,illustration3 ,fig4 #aej4 ,illustration3 ,fig4 #aea4 ,illustration3 ,fig4 #aeb4 ,illustration3 ,fig4 #aec4 ,it is evident that the cutter frame last described having a division plate of its own dispenses with the necessity of one on the pulley of the mandrel4 ,indeed it was the impossibility of supplying the latter on the face of the cogwheel of the author's back-geared lathe that necessitated the substitution of that alluded to4 ,the latter may consequently be omitted if applied to a lathe already fitted with division plate and index4 ,with crank-form drills the cutting edges of which may be as ,e #a1 #b1 #c1 #d1 or other form1 such patterns can be cut1 as shown in ,figs4 #adi1 #aej1 #aea1 #aeb1 which are merely samples of the simplest combinations of circles intersecting in straight1 spiral1 or other lines4 ,although not now treating of eccentric work1 we may state in passing that to produce the pattern round the edge of #aej the division plate of the instrument only is required4 ,select a crank-form drill which by its revolution will produce the required size of circle4 ,turn the divided screw head until you find upon trial that the circle will come at the required distance from the edge1 and putting the lathe in motion cut the first circle4 ,the work on the mandrel is understood to be stationary1 the mandrel being fixed so as not to turn4 ,the cutter frame is now turned on its axis1 one1 two1 or more of its divisions1 and fixed by its detent1 and a second circle cut intersecting the first4 ,this is repeated till the whole circle is completed4 ,the straight line of circles in ,fig4 #aea is cut as follows3--,the first circle is made as before1 but the cutter-frame should be placed so as to stand either horizontally or vertically4 ,between each cut the divided screw-head is moved so many points according to the proposed fineness of the pattern1 and no movement of the cutter frame on its axis is to be made4 ,the spiral1 #aeb1 is simply the result of a combination of the two movements4 ,start from the centre by turning the screw head until the shank of the crank-form drill is coincident with the axis of the mandrel4 ,cut the central circle4 ,thence for each successive circle turn the screw head and the frame an equal number of points1 and the pattern will be formed4 ,if the divided screw head is made to take off and a handle substituted1 stars formed of channelled lines1 or radial flutes can be made as ,fig #aec1 but in this case the crank form drill is replaced by a plain straight tool with a rounded end like #adi ,e #d4 ,set the tool as for pattern #aej straight across the face of the work1 put the drill in rapid motion1 let it be advanced by the leading screw of the poppet so as to penetrate slightly1 and with the handle that has been attached to the screw of the cutter frame cause it to traverse the face of the work as it revolves4 ,when one flute is thus cut1 turn the frame on its axis as many points as required1 and proceed with number two1 and so on to the completion of the star4 ,it is not necessary at present to describe other patterns4 ,fig4 #aec is therefore merely given without special details of the method of producing it4 ,we must now return from this digression to speak of other applications of the slide rest4 ,it is evident that when connection is made between the overhead and a pulley on the screw of the slide rest1 the latter becomes self-acting4 ,the speed is1 however1 far too great1 and in addition1 the mandrel is stationary4 ,the above connection1 therefore1 is not practically possible1 and the overhead is only connected with the pulleys of revolving drills and cutters fixed in the tool-holders of the rest4 ,it is1 however1 very important to be able to form some such connection between the lathe mandrel and the screw of the rest1 for the purpose of cutting screws or spirals4 ,a little consideration will show the principle of this arrangement1 from which some practical plan is not difficult to design4 ,if1 for instance1 the tool simply remains in contact with a cylinder while the latter revolves with the mandrel1 a simple line will be cut round its circumference2 but if1 while the mandrel revolves once1 motion is given to the screw of the rest by which the tool is made to traverse a distance of one-eighth of an inch1 the commencement of a spiral having that pitch will be made4 ,a perfectly smooth surface1 as it leaves the lathe1 in which a slide rest has been used with a point tool1 is in reality cut with a very fine screw thread readily discernable under the microscope4 ,we have1 therefore1 only to devise some method of giving regular motion to the screw of the rest while the work revolves as usual1 in order to turn plain surfaces1 screws1 or spirals4 ,for the purpose of plain turning a plan is sketched by ,nasmyth in the last chapter of ,baker's ,mechanics1 in ,weale's series4 ,a spur wheel is represented fixed to the slide rest screw1 the teeth of which are alternately caught at every turn of the work1 by an arm fixed to the latter1 after the manner of a lathe carrier4 ,this plan is simple1 and might be to some extent used1 but for one defect1 due to the fact that the slides of ordinary rests are the reverse of what is required to make this plan available4 ,the screw which advances the tool towards the work is generally underneath that which moves the tool along the surface of the work4 ,the result is that1 when the tool-holder is advanced to take the deeper cut the spur wheel is brought nearer to the arm which acts upon it1 and greater traverse is thus given to the screw4 ,this is shown in ,fig4 #aed4 ,a is the spur wheel1 ,b the cylinder to be turned1 ,c the arm or carrier4 ,the arrow shows the direction of the movement4 ,now1 if the lathe is put in motion1 the arm will remain in contact with one tooth of the wheel until both arrive at b1 giving a certain amount of motion to the screw1 and thence to the tool-holder4 ,after one cut is thus taken1 the lower screw of the rest is turned to advance the tool nearer to the work1 the effect of which is to cause the arm to extend further over the wheel4 ,suppose its position represented by the dotted line1 it will remain in contact with the tooth till both arrive at c1 having thus traversed a larger arc1 and given more movement to the tool4 ,now if the frames of the slide rest were made to cross in the contrary direction so that the screw to advance the tool towards the work was above that which gave the traverse in the direction of the bed1 this objection would no longer hold1 and the above gearing would answer very well1 since the necessary advance of the tool would not affect the relative position of the spur-wheel and carrier4 ,in ,fig4 #e of the same book1 in which the gearing is effected by two cogwheels1 this alteration in the rest appears in the drawing4 ,in this case the work and rest are connected for screw cutting1 and the arrangement is satisfactory and simple1 and for the amateur especially is the simplest and best that can be devised4 ,the range of screw pitches is however limited1 and the rest must have a left-handed screw1 or the result will be a left-hand thread to that which is cut4 ,hence another device has been arranged1 represented in ,fig4 #aee1 ,a1 ,b1 ,c4 ,a shows the apparatus complete4 ,b is an arm of iron or brass which is about #a_/d inch thick or rather more4 ,this is first slipped over the mandrel screw in front of the poppet and fixed in any desired position by a screw passing through the slot a1 into the face of the poppet4 ,this slot allows the arm to be raised or lowered at pleasure and adjusted1 as will be presently described4 ,in the slot formed in the long arm ,b1 pins ,d with nuts1 fit1 on the rounded part of which cogwheels1 b1 c1 d1 are made to revolve and to gear with each other1 and with a similar wheel attached to the back of the chuck1 ,c4 ,the centre of the outside wheel1 whether one1 two1 or three are used1 is connected to the screw of the slide-rest4 ,for the production of a right-handed screw1 the intermediate wheel comes into play1 simply to reverse the direction of the motion imparted to the screw of the slide rest4 ,the number of teeth which it may contain is of no importance1 the calculation of the change wheel teeth being only necessary with the first and last4 ,the central one is called an idle wheel1 though its work is equal to that of the rest4 ,thus1 suppose the wheel on the chuck to contain #dj teeth1 and the third wheel #bj1 while the former revolves once1 the third will1 if in immediate contact with it1 revolve twice1 introduce an idle wheel with #aj teeth between these two4 ,the wheel1 with #dj teeth1 revolving once1 the idle wheel will revolve #d times--the third wheel twice1 just as if the idle wheel was not in use4 ,in any train of wheels1 if we regard relative speed1 any number between the first and last become similarly idle wheels1 and the ultimate result is the same as if the first and last were in immediate contact4 ,illustration3 ,,fig4 #aed4 ,illustration3 ,,fig4 #aee4 ,take1 for example1 the following train of five wheels1 even numbers being given for the sake of clearness1 to represent the circumferences or number of cogs in each1 ,fig4 #aef4 ,we have here1 as the first and last1 #f in4 and #abj in41 and1 if in contact1 the first must revolve #bj times1 while the latter revolves once4 ,interpose the three idle wheels of #aj1 #cj1 and #fj in4 respectively4 ,during one revolution of the largest wheel1 the second will revolve twice1 the third four times1 the fourth twelve times1 the fifth twenty times1 the same precisely as if the first and last had been in immediate contact4 ,the range of a slide rest-screw is quite long enough for many purposes of the amateur1 and a connection thus made between the mandrel and such screw is what may be termed a miniature of the arrangement adopted in the large self-acting lathes4 ,in the latter1 however1 a leading screw is added the full length of the bed along which the slide rest travels bodily4 ,we may1 therefore1 consider the screw of the slide-rest a leading screw1 and make use of the rules applied in the case of large lathes to decide the proportions of wheels required to cut a given screw4 ,it is plain that when the pitch of the required screw is greater than that of the leading screw1 the revolution of the latter must be at a quicker rate than the former4 ,if1 for instance1 a spiral is to be cut1 like the ,elizabethan twist1 containing but one perfect thread in two inches1 while the leading screw contains twenty threads in the inch1 or forty in the #b in41 the latter must be arranged to make forty revolutions while the former makes one1 because it takes #dj revolutions to carry the tool along #b in41 which is the pitch of the required spiral4 ,the two outside wheels must therefore bear that proportion to one another4 ,forty to one1 however1 would be a practically difficult ratio1 to place as described1 even a pinion of ten teeth on the leading screw requiring #djj teeth on the chuck4 ,hence a different arrangement would be necessary if such very great difference exist between the pitch of the leading or rest screw and that to be cut4 ,the same obvious difficulty would occur where a very fine screw is required1 and the pitch of the leading screw is coarse4 ,this will have to be referred to again4 ,one example1 therefore1 of the method of overcoming this difficulty will suffice4 ,a train of wheels is shown in ,fig4 #aeg1 of which ,a has #fj teeth1 ,b #aj teeth1 ,c1 on the same axle and united to ,c1 #cj teeth1 ,d #bj teeth4 ,while ,a turns once1 ,b will turn six times1 ,c necessarily six times also1 ,d nine times4 ,in this case1 if the first and last had geared together ,d would have made but three turns1 while ,a made one4 ,illustration3 ,,fig4 #aef4 ,illustration3 ,,fig4 #aeg4 ,the following is an easy method of calculating a series of such change wheels3-- ,write down the number of threads in the screw to be cut1 and also the number of threads in the leading screw2 multiply both by any convenient number likely to give such results as to tally with the cogs in the set of change wheels4 ,suppose it is desired to cut eight threads to the inch1 and that the leading screw has two threads in that length4 ,then3 #h #hj #h #abj #h #afj - #aj -- or - #ae --- or - #bj --- c4 #b #bj #b #cj #b #dj ,if you have either couple of these wheels1 you can put one on the leading screw1 and another on the mandrel1 and fill up the intermediate space with dummies4 ,if the above is inconvenient1 or the wheels are not to hand exactly as required1 proceed thus4 ,if you have the wheel for the mandrel1 and the one you wish to use for the leading screw has only half the proper amount of teeth1 it is evident that the leading screw would revolve twice as fast as required1 for they are proportioned as two to one--or if ,i have the proper wheel for the leading screw1 and the wheel ,i wish to use for the mandrel has twice the proper number of teeth1 it amounts to the same thing4 ,you can get over the difficulty by using any two wheels which are in the proportion of two to one 7say #bj and #dj1 #cj and #fj1 #dj and #hj1 c471 and coupling the two firmly together1 so that the larger wheel of the two works into the mandrel wheel 7or dummy working into the mandrel wheel7 and the smallest into the screw wheel 7or its dummy72 if the speed is wrong in the contrary way1 so that the case is reversed1 the coupled wheels are made to gear in a reversed direction2 and whatever may be the amount of error1 whether such as to cause either mandrel or screw to revolve #a_/h1 #a_/d1 or #c_/d too slow or too fast1 the same arrangement may be pursued1 the coupled wheels bearing that proportion to each other4 ,the above method was communicated to the ,english ,mechanic by a working man1 ,james ,connor1 and is perhaps as easy as any2 but tables are published of change wheels for any pitch1 with any thread of leading screw4 ,where it is not possible or inconvenient to apply the above arrangement1 and where only a few pitches are likely to be needed1 another method can be arranged by connecting the lathe pulley to the overhead motion and thence to the screw of the rest4 ,such an arrangement is shown in ,fig4 #aeh4 ,a is the fly wheel1 ,b mandrel pulley1 ,c1 ,d1 pulleys on the overhead1 ,e pulley and screw of the slide rest4 ,to facilitate calculation1 let diameter of ,c equal that of the part of the mandrel pulley that drives it1 by which it will revolve in the same time4 ,the calculation of the sizes of pulleys1 ,d and ,e1 will be the same as for the cogwheels of the screw-cutting lathe1 circumference and number of cogs being1 so far as calculation is concerned1 the same thing4 ,let the leading screw have eight threads to the inch1 and let it be required to cut a spiral of two threads to the inch4 ,proceed as before by dividing the required number of threads to be cut by the number on the leading screw #b-h #be4 ,the pulley on the leading screw will be therefore one quarter the size of that on the overhead 7which is virtually that on the mandrel as it revolves at an equal speed with the latter74 ,the overhead pulley may be conveniently twelve inches diameter1 and that on the screw three inches4 ,while the mandrel makes one revolution the screw will make four1 advancing the tool half an inch1 and cutting one thread of a spiral in that distance4 ,the next revolution will advance the cutter a second half inch1 cutting a second complete thread of spiral4 ,two threads will1 therefore1 have been cut in the space of one inch as desired4 ,by the above method short screws and spirals of divers pitches may be cut at pleasure4 ,the practical difficulty in this plan is due regulation of the various speeds4 ,illustration3 ,,fig4 #aeh4 ,we here introduce a modification of self-acting lathe for cutting ,elizabethan twist described by ,mr4 ,wilcox in his ,,ms4 before alluded to4 ,the work is here done by a leading screw and toothed gearing1 the principle being that of the ordinary machine lathe4 ,a chuck1 ,a1 with cogwheel attached holds the work as usual1 the back centre being also required4 ,the cogwheel gears with one of less diameter attached to the end of the guide-screw ,b4 ,on the latter works the rest ,c1 in which is a nut of the same thread as that on the guide screw1 and which holds the tool in a notch or hollow upon its upper part4 ,the tool is then used by hand1 but is guided in its course along the surface of the work to be turned4 ,this guide screw1 with the rest and cogwheel1 is mounted on a board as a separate piece of apparatus1 and is1 when used1 clamped on the lathe bed4 ,as the rest is after all little else than a large nut1 it must be prevented from turning round1 and must be arranged to bear the pressure of the tool1 relieving the long screw from the strain that would be thus caused4 ,this is effected by a long flat bar--like the rest of a chair maker's lathe--extending the full length of the bed shown here at ,e1 and supported by standards ,f1 ,f4 ,a projecting part of the rest bears upon this1 and slides along it with the tool4 ,the work is begun with the rest on the right hand1 and some care is necessary as it nears the cogwheel on the left1 when the work must be stopped and the whole run back by hand to its starting-place4 ,this is one chief defect in this apparatus1 for the rest very quickly traverses the length of the screw1 and great delay is caused by having thus constantly to stop the lathe and reverse the motion4 ,the closest attention is also necessary to prevent the rest from overrunning its mark and striking the cogwheel4 ,it is evident that by using different pitches of cogwheels1 many screws of varied threads can be cut in the above lathe4 ,there is1 however1 another defect in the above tool not noticed by the writer of the ,,ms4 from which the description is taken1 namely1 the difficulty 7common to all such contrivances for turning wood71 of obtaining the requisite speed4 ,if the work is put in rapid motion1 without which wood will not be cut clean1 the movement of the rest will be so rapid also1 from the effect of the multiplying wheel1 that the tool will be carried from end to end in a few seconds4 ,we will therefore proceed to describe a modification of this and similar apparatus1 which allows the tool a slow traverse lengthwise of the work1 but gives it immense rapidity in the necessary direction4 ,the following is applicable to the lathe described above1 to the ordinary slide rest worked by hand1 or to the large self-acting screw-cutting lathes used in manufactories1 and is specially adapted for cutting spirals or other patterns in wood4 ,in the ,fig4 #afj1 ,a represents a shank1 which may be made of any shape to fit particular patterns of tool holder4 ,this shank is turned up and becomes a cylinder at ,b1 like that of the ordinary revolving cutter4 ,this part is bored1 and fitted with a steel spindle1 which should be of strength proportionate to the size of stuff likely to be operated on4 ,one end of the spindle is fitted with a brass pulley1 from which a cord is to be attached to the overhead apparatus1 the other end terminates in a round or hexagonal boss1 ,d1 round the margin of which are securely held1 by means of bridles ,b#a or other simple contrivance1 a pair or more of small sharp gouges4 ,this apparatus is put in the tool holder of the slide rest1 set to the angle that corresponds with that of the screw or twist1 and put in rapid revolution by means of the overhead apparatus4 ,the whole rest1 or merely the upper part1 is then put in motion by one of the before-named means1 and the tool advanced to make a cut4 ,however slow the movement of the rest may be1 the cutters move with such velocity as to make clean and beautiful work4#ac ,this may be applied to the slide-rest of the twist lathe1 just described1 or any similar apparatus4 ,in the overhead1 a roller1 supplying the place of the second pulley1 as described in a previous page1 will allow the second cord sufficient power of traverse to keep up a proper position in reference to the pulley ,c4 ,revolving cutters on the same principle as the above1 have of late years come into extensive use in wood-cutting and carving machinery4 ,the steam planes now used in the preparation of flooring boards1 the spoke turning lathe1 moulding and shaping machines for wood are all thus fitted4 ,the gouges or other cutters used must not be placed radially1 but as tangents to the circumference of the boss in which they are fixed4 ,an improvement upon the simple bridle to hold the cutters would be the substitution of ,babbage's tool holder1 four radial arms being substituted for the metal boss above alluded to4 ,this tool is described and figured in ,holtzapffel's ,mechanical ,manipulation1 to which the reader is referred for an accurate description4 ,it chiefly consists of a shank turned up at the end like ,fig4 #afa1 the outside1 at ,b1 being rounded to fit hollow gouges such as ,fig4 #afa;,h2 against this the hollow of the gouge is laid1 and opposite to it1 at ,c1 a small piece like ,d4 ,a band or hoop1 ,e1 is now placed over both the above1 and between the two a wedge-shaped piece1 ,f1 which is intended to bring a strain upon the hoop and tighten it round the gouge4 ,this last piece is attached to the shank or holder by a screw passing through it into the shank4 ,the tighter this screw is worked the lower the central wedge is drawn down1 and the tighter the hoop is made to embrace the tool4 ,this holder is also modified to suit flat chisels4 ,the tool cannot possibly slip1 but can be released in a few seconds if desired4 ,such a termination of two1 three1 or four arms revolving on a spindle in place of the boss would form the best possible circular cutter for shaping lathes4 ,the above lathe for producing ,elizabethan twist introduces the reader to self-acting1 screw-cutting1 and machine lathes1 such as are used in all large manufactories4 ,hand-turning1 indeed1 except in such light work as turning up the heads of small bolts1 and finishing up work which1 from peculiarities of form1 cannot easily be done by self-acting tools1 has become a thing of the past in factories of any pretensions2 hand labour1 in fact1 not only no longer pays1 but is quite insufficient to meet the requirements of the present age4 ,take1 for example1 a piston-rod requiring to be as true as a hair1 to use a common expression1 from end to end4 ,the traverse of an ordinary slide-rest would only enable us to turn a short length at a time1 and the result1 when accomplished1 would not be satisfactory4 ,with a self-acting lathe the tool traverses in a perfectly straight line from end to end1 is returned to its starting-point by a quick traverse1 and the movement repeated until the proper dimensions are attained4 ,the process is not absolutely rapid1 because time is requisite in cutting iron and steel1 but the work is executed as speedily as the nature of the metal to be cut will allow1 and the execution is perfect4 ,of late1 however1 even the above has been improved upon1 for two cutters are used at once--one on each side of the bar1 so that by one traverse of the rest a cut of double depth is taken1 and the tendency of the work to spring away from one tool is counteracted by the operation of the other4 ,but we require something more than speed in the present day4 ,we must have work of absolute truth of measurement4 ,what would our ancestors1 or the immortal ,watt himself1 think of measuring work to the hundredth part of an inch1 yet it can be and is done to the thousandth part4 ,i believe ,i am correct in saying that ,whitworth constantly gauges work to that or even a higher degree of nicety4 ,it is not too much to assert that the best engines of the present day really work with the precision of clockwork1 and even the bore of an ,armstrong or ,whitworth gun is executed with no less accuracy and precision4 ,look again at that ponderous affair1 the steam hammer1 so ponderous as to require a depth of solid masonry and timbers to sustain the force of its terrific blows4 ,in a few minutes a solid mass of metal is reduced to a flat plate such as would have taken the united strength of a dozen men wielding the heaviest sledge-hammers for an hour at least4 ,the ground beneath the feet of the spectator trembles at every blow of the machine4 ,the work is done1 and behold6 with a touch the same ponderous concern becomes a nutcracker1 not even injuring the kernel when it breaks the shell4 ,such is one of a hundred specimens of accurate workmanship carrying out in practice the clever designs of the mechanical engineer4 ,sweep away self-acting machinery1 and such work would become a simple impossibility4 ,again1 so long as turning1 boring1 planing1 and such work was performed by hand alone 7even after the introduction of the slide principle71 an attendant was required at each machine4 ,now that the latter is contrived to regulate its own movements1 one man at two or three lathes is sufficient4 ,thus the same article that was once imperfect and costly1 owing to the demand on skilled labour1 which was difficult to procure and at best inefficient when procured1 has now become cheap1 and to all intents and purposes perfect2 and although the demand for such work increases year by year1 self-acting machinery being constantly improved and simplified1 enables the manufacturer to keep pace with the demand4 #ac ,the spiral chuck for fine work in ivory and costly woods is described in a later page4 ,illustration3 ,,fig4 #aei4 ,illustration3 ,,fig4 #afj4 ,illustration3 ,,fig4 #afa4 ,the advantages of self-acting machinery are of course chiefly confined to the trade1 and it is not often that the mere amateur requires such aid4 ,indeed1 the expense necessarily attendant on the fabrication of these machines deters the great majority from making such a purchase4 ,,self-,,acting ,,and ,,screw-,,cutting ,,lathes4 ,the first requisite for fitting up a lathe for screw-cutting and plain turning is the fitting a guide-screw1 and adding a saddle to the slide-rest4 ,but it must be observed that the ordinary mandrel of small foot-lathes1 which works in a collar and back centre1 is not convertible1 and must be replaced by one working through two collars1 so that a part may project at the opposite end to that intended for the chucks4 ,on this projection various cogwheels have to be fitted4 ,now there are divers patterns of mandrel suitable for the above purpose2 some are perfectly cylindrical1 some have one conical part1 some are fitted with a second cone1 independent of the mandrel1 and which slides upon it1 and can be adjusted by means of regulating nuts4 ,this latter being a good pattern1 when well constructed1 we shall first describe in detail4 ,in ,fig4 #afb is shown ,a1 the mandrel complete1 with fittings in section1 but without any of the change wheels4 ,the cone a is forged on the mandrel1 which then becomes cylindrical4 ,the cone is figured too large in proportion to size of mandrel2 the latter should be represented as much more substantial4 ,at b the second cone slides on1 the latter shown again at ,b4 ,it is bored truly1 and a slot cut to fit a feather on the mandrel4 ,thus it will slide along it1 but must necessarily turn with it4 ,beyond ,d on the left are two screwed parts1 one slightly larger than the other1 one being made with a left-handed1 the other with a right-handed thread4 ,on these screw the two nuts1 d1 e1 which drive the movable cone towards the right1 causing it to fit more tightly into its collar1 and also by the same movement tightening the fixed cone in its bearings4 ,the mandrel is thus readily adjustable in the collars1 and can be made to run very truly and easily without shake or endlong movement4 ,any pressure1 however1 against the front1 such as would be caused by drilling1 would jam the front cone in its collar1 and tend to loosen the other4 ,this is counteracted by the part f1 g1 with its screw1 h1 against which the end of the mandrel bears4 ,that this form requires good workmanship is evident1 for there are three points1 or bearing surfaces1 to be brought into a correct line1 and the slightest deviation will cause the mandrel to jam in some part of its revolution4 ,the nuts screw up in opposite directions to counteract the tendency in either to screw up more tightly1 or to become looser by the revolution of the mandrel4 ,on the whole the above is a good form of mandrel2 if it has a fault1 it is a slight tendency to work heavily4 ,the next form is that of the ordinary mandrel1 with single cone1 but a second collar is added1 which is cylindrical1 through which the mandrel passes1 and it then abuts on the sustaining screw as before4 ,this is shown in ,fig4 #afc1 with the addition of the wheel1 which is to be connected by intermediate wheels and pinions with the leading screw4 ,if the conical collar is replaced by a cylindrical one1 so that two similar bearings are made use of1 a shoulder becomes necessary to prevent the mandrel from slipping endwise4 ,the collars must also be split as in ,fig4 #afd1 so that they can be tightened up as they become worn4 ,either of the above forms of mandrel can be used2 each has its advocates1 and not unfrequently all may be found in different machines in the same manufactory4 ,the bed of a self-acting lathe requires to be accurately surfaced1 and formed by the planing machine with two ,v's or edges bevelled underneath1 as #afe b1 b4 ,the saddle of which we have spoken is a flat plate of cast iron fitted with ,v pieces to match the bevelled edges of the lathe bed1 along which it slides truly1 its under-edge being planed4 ,to this plate the slide rest is attached securely1 either turning when required on a central pin1 and being clamped at any desired angle1 as before stated when treating of the compound slide rest1 or1 when this movement is preferred to be given to the upper slide1 fixed permanently by nuts and screws4 ,the saddle is represented detached in ,fig4 #aff4 ,the principle of the self-acting lathe is very simple4 ,motion is given to the screw by means of cog wheels geared with the mandrel1 a nut fitting the screw is attached to a hanging bracket of the saddle1 and this with the rest is thereby carried along the bed4 ,it is necessary1 however1 to add some contrivance for instantly throwing the screw out of gear1 without the necessity of stopping the lathe itself4 ,there are many ways of effecting this1 the most common being the use of a split nut1 which embraces the leading screw when the two halves are brought together upon it1 but which is instantly freed by separating them through the action of levers and cams1 or other simple mechanical contrivance4 ,in ,fig4 #afg1 a is the bottom of the saddle from which depend the brackets ,e1 ,e4 ,the nut ,b1 ,b1 which is divided across the middle1 slides up and down between these brackets1 ,d being the leading screw which they embrace when closed4 ,the movement of the halves of the nut is effected by the lever c1 in the form of the letter ,t moving on a centre pin at ,k1 and having two links1 ,d1 ,d1 attached to the halves of the nut at one end1 and to the ends of the cross lever at the other4 ,a connecting bar pivoted to the part1 ,l1 is attached to a lever and handle1 by which motion is communicated to the lever4 ,when this rod is moved in the direction of the arrow the links will cause the nut to close and vice versa4 ,the next form1 #afh and #afi1 represents the split nut attached to two arms1 ,a1 ,a1 hinged together at ,e4 ,b1 ,b1 are slots in which work the pins attached to the cross head of the levers ,c1 ,c4 ,a heavy knob of iron keeps the latter in the position to which it may be moved4 ,in #afh the pins keep the arms and nuts apart4 ,when the lever is thrown over1 as in #afi1 the nut is securely closed and held in gear4 ,this form requires to be fixed to the lower part of a bracket attached to the saddle of the slide rest1 such as is shown at ,b1 ,c1 ,fig4 #agj4 ,in this figure1 ,a is the bottom of the saddle ,e1 ,e1 the ,v piece1 that on the left1 having an adjusting screw to tighten it on the lathe bed when necessary4 ,at ,f is a projecting piece of the saddle fitting accurately between the lathe bed1 and kept down by a screw with bed plate underneath4 ,this serves to steady the movement of the saddle and relieve the pressure and strain upon the ,v pieces4 ,the bed-plate may be cut out to fit the lower part of the bed on which it slides1 both being planed for the purpose1 as shown at ,h4 ,illustration3 ,,fig4 #afb4 ,illustration3 ,,fig4 #afc4 ,illustration3 ,,fig4 #afd4 ,illustration3 ,,fig4 #afe4 ,illustration3 ,,fig4 #aff4 ,illustration3 ,,fig4 #afg4 ,illustration3 ,,fig4 #afh4 ,illustration3 ,,fig4 #afi4 ,illustration3 ,,fig4 #agj4 ,illustration3 ,,fig4 #aga4 ,in ,fig4 #aga the half nuts slide up and down on the front of the saddle1 and are moved by a circular plate on the outside4 ,the action is very similar to that of ,fig4 #afg1 intervening links1 attached to the plate and to the halves of the nuts1 giving motion to the latter as required4 ,cams and eccentrics of varied forms are also made use of for the same purpose1 every lathe maker devising new and improved movements from time to time4 ,there is indeed little difficulty in arranging a satisfactory method1 the best being that which is under easy control1 of adequate strength1 and not likely to be easily disarranged by the rough treatment it is liable to receive at the hands of the workman4 ,the leading screw may either be placed on the outside1 in front of the bed next to the workman1 or inside between the bearers4 ,the former is preferable as being more accessible1 but it is rather more exposed to injury4 ,when between the bearers the large saddle of the slide rest serves to protect it from the falling chips and shavings of metal which1 mixing with the oil1 are apt to clog the threads and add to the friction of the parts1 besides increasing considerably the wear and tear1 and no accidental blow is likely to reach the screw thus protected on both sides by the lathe bed4 ,nevertheless1 all the various parts of a machine should be made as accessible as possible1 and1 with the exercise of ordinary care in its preservation1 the position outside is on the whole the best4 ,if the lathe bed is very long1 it may be desirable to support the screw by allowing it to rest on friction wheels fixed to the saddle at both ends1 or by allowing it to pass through a pair of brasses4 ,thus1 as the saddle is often two feet in length1 such bearings at each end1 with the split nut between the two1 form points of support which go far to prevent the screw from jagging or bending in the middle from its own weight4 ,the general arrangement of self-acting tools is similar with all the makers4 ,fig4 #agb is a drawing of such a tool from a sketch of ,eades ,son1 an old firm in ,lichfield-street1 ,birmingham1 the screw being here placed in front4 ,whitworth1 the eminent mechanician of ,manchester1 makes many lathes with the screw between the beds4 ,he also uses a double slide rest1 with a tool working at each side of the piece to be turned1 which cannot thus spring away from the cut4 ,this is called a duplex slide rest4 ,by this method double the cut is taken1 and the strain upon the work lessened4 ,in addition to the screw there is usually a rack attached to the lathe bed1 on the furthest side1 and a cog wheel working upon this1 attached to the back of the slide rest saddle1 is turned by a handle in front of the rest1 ,fig4 #agc4 ,this enables the workman1 after having1 by means of the screw1 completed the cut to the end of the work1 to run the rest back again very quickly1 having first released the split nut from the screw4 ,the tool is thus brought into position for the next cut far more rapidly than could be managed by reversing the motion of the screw4 ,this is called1 therefore1 the quick return motion1 and is almost always attached to the larger class of machine-lathes4 ,before entering upon the details of other forms of gearing1 and the arrangement of change-wheels for cutting screws or for plain turning1 we shall introduce a few remarks upon the often-repeated question as to the advisability of self-acting lathes for the purposes of the amateur4 ,it must be remembered that the chief object of such a lathe is the manufacture of large screws1 long shafts1 and such work as the piston rods of engines1 requiring perfect accuracy from one end to the other4 ,boring cylinders and similar work is now generally done in an upright or vertical boring machine1 which is for many reasons more convenient4 ,this class of work1 of course1 the amateur has nothing to do with4 ,the traverse of an ordinary slide rest is generally adequate for surfacing or boring to a length of six inches1 which is sufficient for most purposes1 and can readily be done by turning the leading screw of the rest by hand4 ,then1 as regards screw cutting in the lathe1 it is questionable whether it is not easier to turn up the blank and cut with stock and dies4 ,the thread thus formed is a copy of that of the tool1 and the latter1 as made by ,whitworth and other first-class makers1 is as perfect as machinery directed by talented workmen can produce4 ,if it is really desirable1 however1 to make use of the lathe for this purpose1 the plan already suggested is generally applicable1 namely1 gearing the leading screw of the slide rest to the mandrel1 either by means of change-wheels attached to an arm1 or by connection with the overhead pulleys4 ,there is1 in addition1 a plan of attaching a pair of dies to the tool holder of the rest1 after detachment of the screw from its nut1 which may be available in some cases4 ,there are also screw plates made in two halves1 the plates being divided lengthwise and clamped together at pleasure1 admitting of application to any screw-blank while revolving in the lathe2 and1 lastly1 pairs of dies1 fitted like pliers1 can be similarly used by hand without any slide rest4 ,on the whole1 then1 it will hardly pay to give #ej1 or #fj1 for a screw-cutting lathe that is merely destined for small work2 that can be done sufficiently well in a common lathe with hand motion to the rest4 ,for cutting short screws1 such as those of boxes1 a convenient and practically useful contrivance is still a desideratum4 ,the traversing mandrel is1 no doubt1 the best1 but it is an expensive pattern1 if well made1 and it is necessary to sacrifice1 in a measure1 general utility to questionable and certainly partial advantage4 ,turning is1 moreover1 an art1 and to attain skill in it1 perseverance and practice are necessary--hence the zest experienced in its pursuit by the real lover of it4 ,this perseverance pays1 and to attain the skill required to trace a short screw with the chasing tool is within the reach of any one who desires to accomplish it4 ,the art once acquired1 the desire for a traversing mandrel ceases2 for no good workman would accept a contrivance of the kind when he can more easily and quickly accomplish his end without it4 ,writing this for the special benefit of amateurs1 we would strongly advise them not to throw away money to purchase the means of doing what after all they will probably never1 and certainly only seldom1 carry into practice4 ,the pleasure afforded by all the mechanical arts is greatly enhanced by meeting with and triumphantly surmounting all sorts of difficulties4 ,let it be a standing rule of our readers to make use of the appliances at hand instead of seeking others which only save trouble and render skill unnecessary4 ,what can be more aggravating than for an amateur1 with his hundred guinea lathe and chests of tools1 to be obliged to take his work to a mechanic1 and to see him1 whose whole stock might be bought with perhaps a tenth part of the money1 take in hand and finish with ease what has baffled the skill of his more wealthy patron8 ,the common fault of the amateur is undue hurry4 ,to him time is seldom an object1 yet the mechanic1 to whom it is so precious1 readily spends more upon his work4 ,he never hurries1 never compromises1 but with lathe and file fits the several parts of his work with the most patient care and practised skill4 ,the result is at once seen when his productions are placed side by side with those of the zealous but too hasty amateur4 ,it remains1 as previously described1 to arrange certain cogwheels gearing with each other upon the spindle of the mandrel and upon the end of the screw1 to enable the workman at pleasure to vary their ratio of speed1 in order to give him the means of regulating the pitch of thread to be cut4 ,for this purpose a set of change wheels is supplied with the screw-cutting lathe1 the number of cogs in which usually commencing at fifteen1 increase by five1 until the number one hundred and twenty is reached1 then increasing by ten up to the complete set4 ,duplicates of some numbers are also convenient4 ,the method of finding the proper sized wheels is1 of course1 based upon the proportion borne by the required pitch to that of the leading screw and one form of calculation for the purpose has already been given4 ,thus1 supposing the leading screw to have two threads to the inch1 it must revolve twice to move the tool that distance1 and if we wish to cut a screw of ten threads to the inch1 the work on the mandrel must revolve ten times while the leading screw revolves twice1 or1 which is the same thing1 the mandrel must revolve five times while the screw revolves once4 ,the cogs in the wheels must therefore be in the proportion of five to one1 say fifty on the screw and ten on the mandrel1 with an idle wheel on the stud to cause the motion of the tool to be such as will cut a right-handed thread1 or to cause the mandrel and screw to take the same direction4 ,now1 it seldom happens that two wheels and an idle one will give the requisite speed to the tool1 and the number of cogs required soon mounts to inconvenient numbers4 ,in this case1 therefore1 according to a principle already laid down1 a stud-wheel with a pinion attached to the same1 is placed in the train of wheels1 and the object readily attained4 ,a modification of the rule of calculation may make the system of change wheels still clearer4 ,let the pitch of guide screw be as before1 namely1 two threads to the inch1 and let five be required4 ,place the numbers thus1 #b-e1 and divide both into their factors1 twice one1 or #b #a1 and twice two and a half1 or #b-a_/b #b4 #b #a -------- #b-a_/b44b ,now1 it is certain you can have no wheels containing half notches1 nor of such small numbers of cogs1 therefore multiply by any convenient numbers--ten1 for instance1 which give #bj44aj ------4 #be44bj ,this is all that is needed4 ,put a wheel of twenty cogs on the mandrel1 and let it work into one of twenty-five on the stud1 the latter carrying a pinion of ten cogs1 driving one of twenty cogs on the screw4 ,to prove this1 as before1 the screw must make two revolutions to carry the tool one inch1 and during that time the mandrel 7carrying screws to be cut7 must make five revolutions4 ,let the screw wheel revolve twice1 the pinion of ten teeth will revolve four times 7twice #bj #dj and four times #aj #dj72 but as the stud wheel and pinion are as one1 and revolve together1 the stud wheel must also revolve four times 7#d #be #ajj74 ,thus the mandrel wheel will revolve five times as required 7#bj #e #ajj74 ,no other method is so easy to understand and work as the above4 ,to give full details and provide working drawings of the various screw cutting lathes by different makers would be to extend the present series to an unnecessary limit1 but we shall nevertheless describe another method by which these lathes with traversing rests are made self-acting when screw cutting is not required4 ,instead of a leading screw extending from one end of the lathe to the other1 there extends a bar of steel about the diameter of the screw with a key groove or slot from end to end4 ,this bar is supported in bearings at each end1 and carries upon its surface a ferrule of steel with a screw cut upon its outside similar to ,fig4 #agd1 where ,a is the bar and ,b the ferrule4 ,the pitch of screw is coarse1 being similar in its object to the guide screw previously described4 ,a pin fixed into this ferrule falling into the slot permits it to travel along the bar but causes both to revolve together when the bar is put in motion by means of a cog wheel or strap pulley at one end4 ,along the same side of the lathe bed1 and level with the surface1 is a rack1 ,c1 upon the face of which works a pinion1 ,d1 carrying on the same axis a cog or rather worm wheel1 ,e1 to gear with the screw ferrule4 ,the bearings of this axis are secured to the saddle of the slide rest4 ,consequently1 when the bar revolves1 the screw is also put in motion1 the wheel1 ,a1 ,fig4 #age1 and pinion1 ,b1 partake of the movement1 and the latter traverses the face of the rack1 carrying the saddle with its rest and tool holder along the bed of the lathe4 ,by this movement the screw ferrule traverses the bar as it revolves1 thereby virtually becoming a long leading screw4 ,in ,fig4 #agf1 which is a view from above1 looking down upon the lathe bed1 ,a is the rack1 ,b1 ,b1 the saddle cut away to show the rack and pinion ,c2 ,e is the worm wheel1 ,d the long bar1 the screw ferrule1 being under the worm wheel1 is not visible4 ,as above arranged it is evident that the ferrule might escape from the worm wheel instead of proceeding on its proper course4 ,this is prevented by its lying in the hollow of a bracket attached to the rest1 as ,fig4 #agg1 ,a and ,b4 ,this retains it in contact with the worm wheel1 and also becomes a support to the long bar4 ,fig4 #agd shows the side of the lathe that is furthest from the operator4 ,the axle of the worm wheel and pinion carries a handle on the near side to give the workman power to use the rack by hand as a quick return movement4 ,the above is frequently attached to those lathes provided with a long screw1 the latter being on the near side and the bar on the other4 ,thus1 the same lathe can be used for ordinary or screwed work4 ,whitworth1 however1 commonly uses the long screw placed between the beds or bearers of the lathe for screwing and surfacing1 instead of adding the apparatus just described4 ,a long screw being1 however1 an expensive affair1 ought to be carefully cherished1 and when the work is such as the bar will suffice to accomplish1 it may be well made use of to preserve the screw4 ,there is an arrangement for forward or cross-feed in the above apparatus1 the principle of which is the connection of the cross screw of the rest by means of a pinion1 either with the worm wheel or with a cogwheel on the same axle4 ,when this is put into gear the rack and pinion are disconnected4 ,it is also necessary to provide a method of reversing the motion of the long screw bar1 especially when the cross feed is used in surfacing4 ,there are several modes of accomplishing this1 the best being the following1 ,fig4 #agh1 which is a simple expedient applicable to lathes or other machines4 ,a is the end of the screw rod1 with bevel wheel attached1 ,b1 ,c1 are similar wheels on the axle1 ,d1 the latter being movable endwise in its bearings by means of the lever handle2 ,e1 ,d1 is the driving axle4 ,by moving the lever to the right ,b is geared to ,a4 ,a movement to the left brings ,c into connection4 ,between the two1 both wheels are thrown out of gear1 and though they may continue to revolve1 the screw bar will remain still4 ,by this contrivance the motion of the leading screw is reversed or stopped in a second1 with the advantage of its being unnecessary at the same time to stop the working of the lathe altogether4 ,it has probably struck the reader that as the size of the change wheels are various1 there would be in some cases an impossibility of their touching so as to gear together4 ,this is partly remedied by the interposition of dummies1 or idle wheels1 and partly by the following arrangement4 ,the stud wheel1 or dummies1 as the case may be1 are not upon axles fixed to the lathe-head or end standard1 but upon such an arm as ,fig4 #agi1 which turns upon a pin at ,a1 and carries in the slot the pins upon which the different wheels centre4 ,these pins being made similar to ,b1 ,c1 can be placed at any position in this slot1 and are fixed by a nut underneath4 ,this arrangement gives considerable power of adjustment1 and enables the workman to place together wheels of various sizes according to his need4 ,it would not be by any means difficult to arrange the above lathe for screw-cutting1 especially if the pitch of the required screw is not of great importance4 ,an amateur's lathe might be thus fitted to serve a good many purposes1 although a leading screw is to be preferred as the more complete and perfect arrangement4 ,it cannot1 however1 be denied that there is great friction produced by the worm wheel and endless screw1 which soon tells its own tale by the wear and tear produced1 and the power is not so economically used as it is when the screw works in a nut4 ,expediency1 however1 in this1 as in many similar cases1 must decide for or against the arrangement in any particular case4 ,it is1 at any rate1 a good addition to a lathe provided with an ordinary leading screw1 more especially in the facility with which it can be arranged as a self-acting cross-feed to the rest when used for surfacing4 ,illustration3 ,,fig4 #agb4 ,illustration3 ,,fig4 #agc4 ,illustration3 ,,fig4 #agd4 ,illustration3 ,,fig4 #age4 ,illustration3 ,,fig4 #agg4 ,illustration3 ,,fig4 #agf4 ,illustration3 ,,fig4 #agh4 ,illustration3 ,,fig4 #agi4 ,,wheel ,,cutting ,,in ,,the ,,lathe4 ,among the various uses to which a lathe may be put1 wheel-cutting is one of the most important1 so many pieces of mechanism requiring cogged wheels of various pitches and forms of tooth4 ,by the aid of the slide rest such an apparatus as figured may be readily arranged1 and the work rapidly and accurately performed4 ,the guide by which the cogs and spaces are determined is the division plate already alluded to1 and which is not visible in the present drawing1 but the index of which is shown at ,g4 ,c is the cutter frame with a side pulley 7one on each side7 to conduct the catgut band from the revolving spindle to the overhead motion on to the flywheel4 ,the spindle carries a pulley for the cord and a cutter wheel1 ,i1 to which an exceedingly rapid evolution is given4 ,there are many patterns of these wheels1 the edges of which1 cut into teeth like a fine saw or file1 are the exact form of the spaces required between the cogs2 hence1 some are rectangular1 some have a triangular section4 ,the thicker the wheel to be cut the larger should be the cutter1 so that the bottom of the cut may be virtually level4 ,in ,fig4 #aha another form of cutter is shown1 which if put into sufficiently rapid motion answers as well1 if not better1 than the wheel-shaped cutters4 ,it is a simple short bar of hard steel1 with the edges bevelled in alternate directions1 fitted into a slot in the spindle and held by a wedge or screw4 ,the shape of the end is as before1 a cross section of the space between two teeth4 ,the cutter frame is here arranged to fit into the ordinary tool-holder of the slide rest1 but the form may1 of course1 be varied at pleasure4 ,it will be noticed that the slide rest1 as delineated here1 is different to that of which details have been given4 ,it is made without the sole1 and fits into the socket of an ordinary rest4 ,thus it can be turned on a centre1 and becomes1 to all intents and purposes1 a compound slide rest4 ,it is on this plan the small ornamental turning rest of lighter construction is made4 ,the spindle fitting the socket projects from the centre of the lowest frame1 and is cast in one piece with it4 ,if the apparatus is compactly and strongly made1 it becomes a very serviceable form1 and is much used for the small lathes in sea-going steamers4 ,the sides are made very short1 so that the extent of traverse is small4 ,we may here mention an addition to the rest socket1 enabling the workman to raise this kind1 or that used with drills and cutters1 which is simple and convenient4 ,inside the iron socket a few turns of a screw are cut1 and a second socket of brass with an outside thread is made to fit into it ,figs4 #ahb ,a and ,b1 the latter being a section4 ,the edge of the inside socket is sometimes milled round1 to facilitate holding it by the thumb and finger4 ,in this way the height of the slide rest1 or tee of the common rest1 is adjustable to a great nicety4 ,illustration3 ,,fig4 #ahj4 ,illustration3 ,,fig4 #aha4 ,illustration3 ,,fig4 #ahb4 ,when a wheel is to be cut of large size1 or of substance exceeding that of clock-wheel work1 the above method is not suitable4 ,the wheel is then generally laid flat1 and the cogs are shaped by a slotting machine1 the chisel of which has a vertical motion4 ,the lathe is then no longer used2 as a separate machine is more convenient and economical4 ,a most serviceable addition to a lathe1 especially an amateur's foot lathe1 is the circular saw1 with guides for cutting parallel1 taper1 or mitred work4 ,great rapidity of work is thus combined with perfect accuracy4 ,a five-inch lathe will of course take a saw nearly ten inches diameter1 but it is not advisable to attach one of quite this size1 for the larger the saw the greater is the leverage against which the turner has to contend1 and the friction caused by a deep cut in stuff of two inches diameter is quite sufficient to make the labour considerable4 ,when such work is necessary1 it must be very gently brought to bear upon the saw1 and the flywheel of the lathe should be heavy4 ,the cord should also pass from the latter to the slowest division of the pulley4 ,if the workman1 amateur or professional1 desires a lesson in practical mechanics1 he has nothing to do but turn a piece of ash six inches in diameter1 with the lathe-cord extending from the flywheel to the smallest part of the pulley1 the diameter of which is about half that of the object to be turned4 ,this will teach him what hard work is4 ,then let him try the job with the cord1 from the smallest part of the flywheel rim1 to the largest diameter of pulley4 ,the change to a slower motion and greater power will not be disagreeable4 ,it must be remembered that a circular saw of six inches diameter will not penetrate three-inch stuff1 owing to the boss or nut by which it is attached to its spindle4 ,the above size will not make good work of stuff exceeding two inches in thickness1 and even less thickness would be preferable4 ,as to the size of saw1 indeed1 that is most suitable to a five or six-inch foot lathe1 much depends upon the proposed work1 and still more upon the weight and size of the flywheel4 ,as a general rule it is better to err upon the size of smallness4 ,the service to which this tool is commonly put is but light2 sawing narrow strips of mahogany1 such as used at the angles of bird-cages1 cutting strips or segments of ivory 7for which let the saw be kept wet7 sawing out mitred or dovetailed joints1 and similar work is within the compass of a five or six inch saw1 and it is better not to exceed this4 ,the teeth should be tolerably fine for hardwood and ivory1 and coarser for deal and soft woods4 ,smaller saws of hard steel1 and made of thick plate1 are used for metal4 ,the method of mounting saws of small size1 such as are suited to be worked by the treadle of a foot-lathe1 is shown in ,fig4 #ahc4 ,e is a steel spindle1 of which the diameter equals that of the central hole in the saw ,b4 ,at ,f1 about the middle of the spindle1 is a fixed flange1 at the base of which is a short feather or inlaid key1 ,x #ahd1 which fits the small slot seen in the centre of the saw and reaches also within a similar slot in the movable flange1 ,g1 but it must not be so long as to come through to the back of the latter4 ,this flange and nut ,h having been removed1 the saw is slid upon the spindle till it rests against the fixed flange2 the movable one is now to be brought against it and clamped by the nut4 ,the spindle is sometimes made with a square end to fit the square hole chuck1 and centred at the other1 or it is drilled at both ends1 so as to be driven by the carrier or driver chuck1 ,c1 ,d4 ,it must be so placed as to run towards the operator4 ,the above arrangement must now be made complete by the addition of a platform1 ,b1 on which to lay the work that is to be sawn1 and on which some contrivance can be adjusted to guide the passage of the saw through the same1 so as to cut the work in parallel pieces1 or at any desired angle1 such as would be necessary for mitred joints4 ,for the general uses of the amateur a mahogany or hardwood platform is as good as any1 and such as is delineated in vol4 ii4 of ,holtzapffel's valuable work is perhaps the best arrangement4 ,the saw table rests on the opposite ends of a kind of open box1 which is represented without the two sides1 although they may be added if desired1 and the whole when removed from the lathe would then form a case for the saws1 or serve other similar purpose4 ,the platform is hinged1 so as to overlap1 as seen in the ,fig4 #ahd;,a1 and there is in the middle of it a slit cut by the saw itself1 which1 when it is mounted on its centres will be in the position shown4 ,if sides are added a notch must be made in the upper edge of both for the passage of the spindle4 ,the fillet ,b fits between the bearers of the lathe1 securing the parallelism of the whole4 ,when made with four sides the box must first be placed on the lathe bed and loosely held by the bolt beneath4 ,the saw is then mounted1 and the box adjusted to its place and fixed4 ,the cover is then 7if for the first time7 brought carefully down upon the saw1 and the lathe being put in motion the slit is made1 and its position will be truly at right angles with the spindle and the lathe bed4 ,of course1 in future operations the platform is lowered over the saw before the holding down bolt is permanently screwed up4 ,the sides of the saw-kerf may be edged with brass if preferred1 but on the whole the plan is not to be recommended1 for if1 as will occasionally happen1 the saw should get slightly out of truth1 or vibrate a little when in use1 the teeth will come into contact with the metal and be blunted or broken4 ,if the saw-kerf by constant wear should widen too much1 the whole platform is renewable at little cost1 or a new piece can be let in1 and a fresh saw-kerf made4 ,there are several guides for parallel work4 ,the one shown in ,fig4 #ahe is precisely such as is to be seen in the ordinary parallel ruler--,a is the back bar screwed to the platform at the right-hand edge2 ,b the guide or fence which1 when the connecting links ,c1 ,c are perpendicular to ,a1 should touch the saw2 ,d1 ,d are arcs of circles of which ,e1 ,e are the centres4 ,they may be arcs of brass pivoted to the links and passing through a slot in the bar1 ,a1 ,a1 or may themselves be cut as mortises in the platform1 in which fit a pair of bolts with thumb-nuts passing through the links1 by which to clamp the fence in any desired position4 ,this form of parallel guide is not very substantial1 and is not correct in practice unless the pins are very nicely fitted1 and the links precisely of a length4 ,the second figure shows the sectional form of the fence ,g1 the links being represented at ,h1 and the fixed bar at ,k4 ,the following is a more solid and unyielding guide1 and much to be preferred4 ,holtzapffel attributes it to ,professor ,willis4 ,it is merely a modification of the ,t-square as used with the ordinary drawing board with an arrangement for fixing it in the required position4 ,the present arrangement differs from that in ,holtzapffel's work in the manner of fixing it and the addition of a second ,t-piece on the side next the workman4 ,in ,fig4 #ahf ,a is the upright part of the fence1 ,b the bottom or sole1 to which is attached at each end the ,t or cross pieces1 ,e1 ,e1 which slide along the straight edges of the platform and secure the constant parallelism of the fence to the surface of the saw2 ,c is the groove or slot1 in which a screw1 ,d1 traverses1 and the fence is thus fixed by a turn of the thumb-nut1 ,d4 ,this fence can by no possibility get out of truth2 it is easily removed by taking out the single screw1 and it is far more simple and more easily made than the one previously described4 ,the nearest edge of the platform may be marked in inches and eighths1 and the fence can then be instantaneously adjusted for sawing pieces of any desired width4 ,it is not always1 however1 that straight1 rectangular1 or parallel strips are required1 and an additional arrangement is needed to form a guide for sawing angular pieces4 ,now it is not sufficient to lay the guide fence at a given angle1 for if the latter were arranged for that adjustment by taking off the tees and causing it to turn upon the screw which secures it in place1 and a piece of board were placed against it to be sawn1 the latter would press against the saw sideways as seen in ,fig4 #ahg4 ,the guide fence for angles must itself therefore travel in a line parallel to the saw and carry with it the piece to be cut4 ,the simplest and usual arrangement is that given in ,holtzapffel's work4 ,a dovetailed groove in the platform running in a direction parallel with the saw carries a sector attached to a bar which fits the groove1 and this bar is free to move forward or backward without lateral movement4 ,the piece to be sawn is thus rested against the fence forming the straight face of the sector1 and the whole is moved forward together against the edge of the saw4 ,fig4 #ahh explains this4 ,it will be seen that several grooves are made side by side1 all of which fit the slide alike1 and by moving the latter into either of these a lateral adjustment is effected to suit pieces of different widths4 ,the sliding strip should be made of hard wood and nicely fitted1 and may be lubricated with soap1 or polished with black lead1 either of which will cause it to slide with diminished friction4 ,fig4 #ahi shows a somewhat different arrangement1 by which more lateral adjustment may be given4 ,the sector is replaced by a ,t-square1 the blade of which has a slot through which a screw passes into the sliding bar4 ,a second jointed rod is added1 passing through a staple in the slide1 and by a screw in the latter the ,t is fixed as required4 ,the staple must turn on a centre to accommodate itself to all positions of the ,t-square1 and a second eye may be placed on the opposite arm to allow the guide rod to be removed to that side1 which is sometimes more convenient4 ,the sector also may be made adjustable as in ,fig4 #aij1 and clamped by a simple screw in the slot4 ,either of the above methods will allow sufficient range for small work1 such as is likely to be the object of amateurs or those who add small saws to the foot lathe4 ,the guide for angular pieces may indeed be in many cases dispensed with by making use of patterns of wood chiefly in the form of triangles2 these sliding against the parallel guide1 and carrying the work with them1 will answer well in a number of cases where other provision for such work has not been made in arranging the saw table4 ,it must be remembered1 however1 that in this case the length of the piece 7supposing it to be the side of a picture frame to be mitred7 is limited to the space between the fence and the saw1 which in the more perfect arrangement is an evil plainly avoided4 ,it may sometimes be necessary to cut pieces with various angles not in the same plane4 ,by using the hinged platform1 and adding a screw attached to the front of the box1 and standing perpendicularly1 the front of the table can be raised to a given angle1 but those who are likely to enter extensively into the cutting mathematical figures are referred to vol4 ii4 of ,holtzapffel's work1 where the subject is fully explained and illustrated4 ,the following remarks upon the proper speed of saws and sizes of teeth are copied from that work1 and may therefore be relied on3-- ,the harder the wood the smaller and more upright should be the teeth1 and the less the velocity of the saw4 ,in cutting with the grain the teeth should be coarse and inclined1 so as rather to remove shreds than sawdust4 ,in cutting across the grain the teeth should be finer and more upright1 and the velocity greater1 so that each fibre may be cut by the passage of some few of the consecutive teeth rather than be torn asunder by the passage of one tooth only4 ,for gummy or resinous woods and ivory1 the saw teeth must be keen1 and the speed comparatively slow1 to avoid the dust becoming adhesive 7by reason of the heat engendered by friction71 and thus sticking to1 and impeding the action of the saw4 ,illustration3 ,,fig4 #ahc4 ,illustration3 ,,fig4 #ahd4 ,illustration3 ,,fig4 #ahd4 ,illustration3 ,,fig4 #ahe4 ,illustration3 ,,fig4 #ahd;,a4 ,illustration3 ,,fig4 #ahf4 ,illustration3 ,,fig4 #ahg4 ,illustration3 ,,fig4 #ahh4 ,illustration3 ,,fig4 #ahi4 ,illustration3 ,,fig4 #aij4 ,by raising the platform so as only to expose a small portion of the saw1 it is easy to cut rebates1 grooves for tongueing1 and other work of a similar kind4 ,the above arrangement of hinged table facilitates this application of the saw4 ,,fret ,,saws ,,to ,,mount ,,upon ,,the ,,lathe ,,bed4 ,convenient as the circular saw is when fitted as an adjunct to the lathe1 its use is confined to pieces which are rectilineal4 ,curved lines cannot be cut by its means1 and as it must frequently happen that portions of the proposed work are composed of arcs of various dimensions1 it becomes necessary to provide the means of cutting them out4 ,we may remark here1 that although the circular saw1 and that of which we are about to speak may be fitted to mount on the ordinary lathe bed2 it is better for many reasons to have a separate stand1 made like that of the lathe1 but smaller1 and fitted with crank1 treadle1 and flywheel1 to serve for the various purposes of sawing1 grinding1 or polishing2 the latter operations especially soiling and tending to damage the lathe4 ,the above description of the methods of mounting circular saws will answer for a separate stand1 as will the following details of saws for curvilinear work4 ,in respect of the latter we have to provide for the perpendicular motion of the blade1 which is necessarily thin and narrow1 and also for stretching the blade so as effectually to prevent it from bending or buckling--guides are not required in general1 as the work is moved about by hand in all directions according to the intricacies of pattern to be traced4 ,for plain circular pieces1 however1 a very simple expedient is sometimes used1 which will be described in its proper place1 when treating of ,bergeron's scie mecanique4 ,the guides for parallel motion are various1 and a selection may be made from the following ,fig4 #aia4 ,no4 #a is the arrangement used by ,professor ,willis1 and detailed in ,holtzapffel's work4 ,a1 ,a are wooden springs1 one above1 the other below the platform ,b4 ,c is a guide pulley1 ,d an eccentric4 ,the catgut band which gives motion to the saw may be passed round this1 or affixed to a metal ring as in the eccentric of a steam engine--or may be attached to a ring slipped over the pin of a crank disc1 as shown at ,e4 ,this pin being adjustable1 permits the traverse of the saw to be regulated1 which gives it perhaps an advantage over the first method4 ,in the above the motion of the saw is not truly in a right line1 but the deviation in so short a traverse is unimportant4 ,the reader may1 perhaps1 imagine wooden springs a somewhat primitive expedient1 but this is by no means the case1 as they will retain their elasticity longer than metal ones when they are subjected to the rapid vibration which they are called upon to undergo4 ,no4 #b is the parallel guide1 used by ,mr4 ,lund1 and also described by ,holtzapffel2 the metal springs1 however1 shown by the latter being here replaced by india-rubber1 which is now formed into springs of various sizes and powers suitable for our present and many similar purposes4 ,a1 ,a1 and ,d1 here form guide pulleys1 the saw1 ,e1 being suspended from the first by the two catgut bands1 on the ends of which are the india-rubber springs1 ,f1 ,f4 ,the lower end of the saw is attached to another catgut band which passes over the pulley1 ,d1 and thence to the eccentric or crank disc as before4 ,the platform is at ,b1 ,b4 ,number #c is an arrangement similar to the beam of ,newcomen's engines4 ,the arc at the end of the oscillating rod1 and from the furthest point of which the saw is suspended1 forms the guide for parallelism4 ,underneath the platform the pulley and eccentric may be used as before1 and the saw is raised by the spring attached to the arc as shown4 ,it will be evident on inspection that this arrangement is similar in principal to the last1 as the arc forms part of a large wheel of which the centre is the point of oscillation4 ,watt's parallel motion1 represented in the next diagram1 is also suitable1 the saw being attached to the centre of the short link--the springs being so contrived as to act upon the ends of the longer bars4 ,with regard to the means of producing the necessary rapidity of movement1 the above-described eccentric or crank disc can hardly be surpassed4 ,in the saw patented lately by ,mr4 ,cunningham1 the disc is attached to the mandrel like a chuck1 and the crank pin is connected to the oscillating rods that carry the saw by an intervening rod or link4 ,illustration3 ,,fig4 #aia4 ,no #a4 ,illustration3 ,no4 #b4 ,illustration3 ,no4 #c4 ,illustration3 ,no4 #d4 ,illustration3 ,,fig4 #aib4 ,the whole is represented in ,fig4 #aib1 which is copied from the inventor's circular4 ,there is a satisfactory parallel motion1 and an india-rubber ball with a small tube attached is pressed at every stroke to blow away the sawdust4 ,the whole plan and details are as good probably as can be devised1 and as an addition to the lathe this saw is invaluable4 ,another form of mechanical saw to work with the foot1 but without any flywheel1 is figured by ,bergeron1 and is thence copied into ,holtzapffel's book1 and would therefore have been omitted here were it not that the price of ,holtzapffel's work places it beyond the reach of many whom it is specially qualified to instruct2 and that the former is in ,french and has not been translated4 ,therefore1 as the arrangement of saw is exceedingly good1 the writer has determined to introduce it here4 ,its construction is simple enough to be within the reach of any amateur in carpentry1 and the only metal work required consists of a few iron rods screwed at the ends1 such as the village blacksmith can readily supply4 ,the saws are precisely those sold as turn or web-saw blades4 ,it must be understood that the use of this tool is not the same as that to which fret or buhl saws are applied1 but merely the cutting of boards in strips or curved pieces1 such as the felloes of small wheels1 circular plates to be finished in the lathe1 as bread platters1 or such other curvilinear works as the chair or pattern maker is accustomed to cut out with the several sizes of frame saws4 ,a1 ,b1 ,fig4 #aic1 is a stout bench with cross bar1 ,c1 underneath1 cut away to allow of the movement of the treadle and its rod4 ,on the top of the bench is a pillar1 ,d1 to support the spring bow ,e1 by which after depression the saw is raised to its original position4 ,f1 ,f1 and ,g1 ,g1 are guide rods 7not continuous74 ,the lower ones are fixed to the cross bar1 c1 and under side of the bench4 ,the upper form the sides of a rectangular frame1 ,h1 ,h1 of which the top and bottom bars of wood are dovetailed at the back to slide up and down the chamfered bar behind them1 ,k4 ,the frame thus allows of being raised or lowered1 not only to suit work of various thicknesses1 but also to act as a stop to prevent the saw from lifting the work as it ascends4 ,the lower bar is extended on one side as in the figure1 and is divided into inches1 and on this graduated part is a slide with a point below1 which can be fixed by a screw4 ,this is1 as the drawing plainly shows1 intended for the guidance of the wood in cutting circular pieces4 ,the saw is similar to the ordinary framed saw used by chair makers1 but has two blades1 and one central stretcher4 ,the saw for curved work is narrow1 that for straight cutting is broader4 ,near the latter a parallel guide is fixed1 as described when treating of circular saws4 ,this simple contrivance1 although planned so many years ago1 is of great value1 and deserves to be far more generally known4 ,to the joiner and cabinet-maker it would form a most useful addition to the usual tools of the workshop4 ,illustration3 ,,fig4 #aic4 ,akin to the circular saw are the various revolving cutters used either for the purpose of ornamentation or for grinding1 such as circular files for flat surfaces1 in which the teeth are cut upon the face or tool-cutters of particular sections for cutting the teeth of wheels1 in the manner already described1 to which may perhaps be added milling and embossing tools1 although the action of the latter is rather that of a revolving die by which the work is stamped or indented with the pattern formed upon the edge of the cutter4 ,the small grindstones and emery laps belong also to this section1 as their action results from the abrasion of the material by means of the combined cutting power of innumerable small points or miniature teeth formed by the particles of emery or other material attached to the surface of the laps4 ,most of the steel cutters may be made by the amateur1 the metal being turned to the required shape and the teeth cut by small files or punches while the material is in a soft state4 ,the little discs are then hardened and mounted1 by a central hole previously made1 on suitable spindles1 the latter being either attached at one end to the mandrel as arbor chucks1 or centred at both ends and driven like miniature circular saws4 ,the ornamental cutters for embossing1 ,fig4 #aic;,b1 ,a and ,b1 are turned to the form of short cylinders1 and the patterns cut by punches4 ,these and the milling tools are mounted alike1 ,fig4 #aid4 ,the rest is placed a short distance from the work1 and the tool revolves against it4 ,some pressure is necessary to imprint the design1 and this is easily obtained if the cutter wheel is placed so as to attack the work below the axis2 the rest then becomes a fulcrum1 and the shank and handle of the tool acting as the long arm of a lever supply the required force with little exertion on the part of the operator4 ,in this way the milling is done on the edges of screw heads1 and the embossed patterns on soft wood boxes4 ,it is not easy to understand how the patterns in these cases are produced clearly without one part cutting into and effacing another1 unless the size of the work is exactly a multiple of that of the tool4 ,the error is plain if the work is stopped exactly at the end of the first turn1 but in successive revolutions this error becomes gradually obliterated1 and the pattern is eventually impressed clear and well defined4 ,the same shank is arranged for different patterns of wheel-cutters1 as the pin which forms the central axis is readily withdrawn and is made to suit the holes in several sets of discs4 ,illustration3 ,fig4 #aic;,b4 ,illustration3 ,fig4 #aid4 ,illustration3 ,fig4 #aie4 ,by the aid of the above simple tool a neat finish is readily given to many small works in wood and metal4 ,a modification of the beading tools is here shown very similar to the screwing guide already given1 but made with figured instead of sharp-cutting edge4 ,this was communicated to the ,english ,mechanic1 ,nov4 #b1 #ahff4 ,e1 #aie1 is the guide which is placed on the handle ,a1 ,b1 ,c1 ,d1 and fixed by screw ,f4 ,the mark i1 on the guide1 is placed against the rim1 ,a1 ,b1 which is graduated and numbered4 ,each figure1 as it is brought up and placed opposite i1 will cut a different pattern when the guide is fixed4 ,the tool must be held very firmly on the rest 7the bottom of the guide ,g1 ,h1 being flat1 is carried on the rest71 the tool is advanced to the wood4 ,the tool must be worked very steadily2 but with a little practice1 any amateur will soon use it perfectly1 and produce many very pretty patterns4 ,it is evident that provision is here made for placing the cutter at different angles to the work1 by which means the circles of patterns may be traced spirally and in other positions varying from the ordinary one at right angles to the axis of the work4 ,the laps alluded to1 which are to be mounted on spindles like the circular saw1 are composed of wood and metal of determinate forms4 ,first1 there is the thin sheet-iron slitting wheel used by lapidaries1 and which1 when charged with emery1 or sand and water1 forms the nearest approach to the circular saw4 ,it is1 in fact1 the circular saw of the stone worker1 the ordinary saw used in their trade being a flat blade without teeth1 stretched in a wooden frame and similarly fed with sharp sand and water in lieu of being made with teeth1 the latter being replaced by the grittiness of the material4 ,the circular plate of iron1 brass1 or lead alloyed with antimony1 mounted on a spindle vertically1 is used in a similar manner for grinding flat surfaces with the aid of emery1 crocus1 oilstone powder1 and other substances1 and the same is used edgewise for other work1 as grinding and polishing tools1 the section of the lap being such as will form the article required by reproduction of the revised plan of its own edge4 ,thus a lap running horizontally with a convex edge will produce the concave form required in beading tools1 the latter1 however1 are more conveniently ground on brass cones mounted like the arbor chucks used for turning washers1 rings1 c4 ,the face of the tool or flat side is held towards the small end of the cone1 and the latter is armed with flour emery4 ,see ,fig4 #aif4 ,illustration3 ,fig4 #aif4 ,before describing the eccentric and other compound chucks1 a few examples will be given of the method of turning some of those forms in which the circle does not appear1 where1 in short1 the boundaries of the figures are straight lines4 ,it seems at first sight impossible to produce in the lathe by any simple means such solids as are formed from squares or triangles1 of which the cube or die is the most common and most generally understood4 ,this can1 however1 be accomplished1 and a number of mathematical problems may be clearly demonstrated to the eye by such works skilfully made in the lathe4 ,in this kind of work it is absolutely necessary to strive after perfection4 ,in short1 as ,bergeron rightly says1 the work imperfectly done is simply worth nothing at all2 but when accomplished with exactness1 nothing can be more worthy of a place in a cabinet of curiosities4 ,the usual method of turning a cube is by shaping it out of a perfect sphere1 but as the latter can hardly be made without a special slide rest made for the purpose1 a method of turning the cube by hand alone will be given1 the foundation of it being that which the lathe so readily produces1 namely1 a cylinder4 ,by far the most proper material for the work in question is sound boxwood1 and special care is to be taken to keep all angles as sharp as possible1 and therefore to cut clean with sharp tools1 and to avoid as far as possible the use of sand or glass paper4 ,fig4 #aig shows a square described in a circle4 ,the non-mathematical reader may be told to draw through the centre two diameters at right angles to each other1 and to complete the square1 as in the figure1 by joining the extremities4 ,the largest square that is possible to be drawn in the circle is thus described4 ,this square will form one face of the cube1 and the diameter of the piece of wood must be regulated according to the proposed size of the finished work4 ,it is evident that this diameter is equal to the line drawn from corner to corner called the diagonal of the square4 ,now1 in turning a ball or sphere1 a cylinder would be turned of the exact length of ,a1 ,c1 because every measurement taken on a diameter of the sphere would be of that length4 ,in the present case1 however1 the cylinder must be of the same length as the line ,a1 ,b4 ,turn1 therefore1 with great care a cylinder of any desired size1 gauging it carefully with the callipers and squaring off the ends truly4 ,on one end1 in which the centre point just remains visible1 draw diameters and construct the figure #aig4 ,turn out a chuck to fit it exactly1 and let the bottom of this chuck be truly square4 ,take the precise length of the line ,a1 ,b1 with finely pointed compasses that can be fixed with a screw1 and measure off the same1 and mark it on the side of the cylinder4 ,when the figure is placed on the chuck1 a mark must be traced round it at this point1 ,a1 ,b1 ,fig4 #aih1 and this must remain to the end4 ,it may be made with a hard pencil or steel scriber1 and1 though distinct1 must be very fine4 ,it is at this line the wood will have to be cut off1 but in this operation keep beyond it so as not to erase it4 ,while the piece is in the chuck1 rule lines1 as ,e1 ,g1 from the points ,c1 ,d1 ,e1 ,f1 #aih4 ,bisect also the length of the cylinder by the line1 ,h1 ,k1 also finely drawn4 ,draw two more diameters1 as shown by the dotted lines bisecting the sides of the cylinder1 which is now divided round its circumference into eight equal parts4 ,the lines1 ,e1 ,g1 c41 can be ruled along the edge of the rest1 or1 if the latter is untrue1 the cylinder may be laid on a plane surface1 and a scribing block1 or gauge1 ,fig4 #aii1 may be drawn across it1 or1 lastly1 a small steel square may be used2 one part being carefully placed on the lines at the end of the piece in succession1 the other part will lie evenly along the side1 and will form a ruler by which to work4 ,a division plate on the lathe pulley will facilitate the above measurements1 but they can be readily made without it1 and once carefully marked1 all the guides required for cutting out the cube will be complete1 and the work can be proceeded with1 with confidence and decision4 ,proceed1 therefore1 to cut off the piece at ,a1 ,b1 with a parting tool1 but with the precaution already named of not erasing the line by so doing4 ,now prepare a chuck which will take the piece lengthwise1 ,fig4 #aii-b1 and insert it in that position to the depth of the diameter so as to hold it securely1 and the central line will show whether it lies evenly 7which is1 in fact1 the use of this line74 ,if even1 a point-tool held on this line will form a mere dot upon it2 if uneven1 it will make a circle as it revolves4 ,place the rest across the face of the work1 and1 beginning at the centre1 cut carefully towards the outside until you have cut away the wood as far as the line1 ,a1 ,b4 ,you will thus complete one face of the cube1 and an inspection of the end of the piece1 shown black in the sketch to show the quantity removed1 will prove that you thus produce a right line1 ,c1 ,d4 ,take out the work1 and reverse it1 and operate similarly on the opposite face2 but in every case do not quite obliterate the lines first marked as guides4 ,you have now a piece shaped like ,fig4 #bjj1 ,a and ,b1 and must make a smaller chuck to hold it2 you have then to cut away in a similar manner the remaining parts of the cylindrical portion1 and the cube will be complete4 ,to finish the sides more neatly1 lay upon the table the finest sand paper1 and tack it at the corners1 and with gentle movements work down precisely to the guide lines4 ,this requires extreme care1 for if once the piece is but in the slightest degree tilted up1 an angle will lose its sharpness1 and the beauty of the work will be marred4 ,hence we recommend to cut with sharp tools1 instead of trusting to the finishing process4 ,to cut1 however1 exactly to the line is very delicate work1 and to the less practised hand the use of the sand paper on the faces in succession may be the necessary expedient4 ,the main secret of sharp edges in works of wood and metal is to finish with hard substances1 as emery stick or glass paper glued to a piece of wood1 or the same nailed on the bench1 and to try always to work on the centre1 leaving the edges or angles to take care of themselves4 ,when the reader has made a cube1 as above1 that will bear delicate measurement1 he will be more than usually gratified1 and will be qualified for still more difficult work4 ,a chuck figured by ,bergeron1 ,fig4 #bja1 is very convenient1 as it holds the work truly central2 the jaws work simultaneously by a right and left-handed screw as in the die chuck4 ,it is1 however1 perfectly easy to do good work without it1 but the chucks should be carefully made1 turned very flat at the bottom1 with side truly perpendicular4 ,a little extra care bestowed upon chucks will save many disappointments1 and conduce to good work4 ,the formation of a four-sided solid1 consisting of triangles solely1 in the lathe is a work of difficulty1 owing to the impossibility of fixing the work satisfactorily in an ordinary chuck4 ,the natural way to form such a solid is to turn a cone ,a1 ,b1 ,fig4 #bjb1 and on its base to mark a triangle of the required size4 ,it is then necessary to place the cone in a chuck1 so that the ends of one of the lines thus marked and the apex of the cone are precisely level with the surface of the chuck1 as shown in ,fig4 #bjc4 ,but it is evident that adequate support is not thus obtainable4 ,the apex of the cone cannot1 in point of fact1 be inside the chuck at all1 as it is necessary to cut clean to its extremity1 and even the base of the cone is imperfectly held at two points4 ,hence it becomes necessary to make use of turner's cement1 and to imbed the work fairly in it1 while both are warm1 to such a depth as will hold it securely and still allow the guide lines to be seen4 ,the latter should be carried from the three angles of the triangle marked on the base to the apex4 ,on the whole1 this is the easiest method of fixing such work in the lathe2 and if the piece is itself warmed before being placed1 there will be time to adjust it precisely before the cement is cold4 ,to do this1 place the rest parallel to the lathe bed1 hold a pointed tool steadily upon it1 and note whether1 as the work slowly revolves1 the three points in question1 viz41 the two angles of the triangle and the top of the cone1 are in one plane4 ,when they are so placed1 the rest is turned to face the work1 and the material is carefully cut away till the gauge lines are just reached4#ad ,a pyramidical solid with a square base may be similarly turned4 ,the following is the method of preparing the above turner's cement3--,burgundy pitch1 #b lb42 yellow wax1 #b oz4 ,melt together in a pipkin1 and stir in #b lb4 of ,spanish white4 ,when the whole is well mixed1 pour it out on a marble slab and roll it into sticks4 ,fine brickdust1 whiteing1 or any similar substance finely pulverised1 will answer equally well to add to the pitch and beeswax4 ,this cement is very useful1 as it will hold the work firm enough to turn carefully1 and nevertheless a slight blow will loosen it4 ,to clean it off1 warm or dip the work in hot water and wipe quickly with a piece of cloth4 ,the above is from the ,handbook of ,turning1 the author of which has copied from ,bergeron both the recipes given in his work2 the one here described is stated to be specially serviceable in cold weather4 ,it is perhaps rather less brittle than the first of ,bergeron's1 and for this cause is the best for general use4 ,holtzapffel sells this at one shilling the stick1 which is of convenient size and generally of excellent quality4 ,bergeron gives a method of turning pilasters or balustrades1 which is of great ingenuity1 and applicable to work of various sections4 ,the rectangular and triangular sections illustrated are not1 indeed1 strictly rectilineal figures1 as the sides of the balustrades thus formed are not flat but rounded surfaces2 they are1 however1 sufficiently curious1 and when well turned are interesting specimens of lathe work4 ,bergeron's description relates to the pole lathe1 or to work mounted between two centres with a pulley cut on the work itself to receive the lathe cord4 ,the ordinary method of mounting on a foot-lathe will1 of course1 be much better and the whole operation of more easy performance4 ,let it be required to turn a moulded pillar or balustrade of the section ,fig4 #bjd1 viz41 a triangle with slightly curved sides4 ,a piece of wood of the requisite length is planed up accurately to a triangular form1 or1 as it generally happens that a set of such pilasters are required1 a number of such pieces are prepared which must be accurately planed to the same size1 for which purpose a gauge or template1 ,fig4 #bje1 should be made use of4 ,six or eight of these1 if not too large1 may be operated upon at the same time2 but as six pieces of two inches across each face require a cylinder of about eight inches diameter1 the number must depend on height of centres4 ,the larger the cylinder1 however 7which1 in fact1 forms a chuck71 the more nearly will the sides of the finished work approach to plane surfaces1 as they will form arcs of a larger circle4 ,let a cylinder1 then1 be turned of sound wood with a reduced part at one end so as to form a shoulder4 ,divide the circumference into twice as many equal parts as there are pieces to be turned1 the divisions being equal to one of the sides of these pieces as measured in a cross section4 ,these divisions are to mark the positions of the grooves or channels in which the triangular strips are destined to lie4 ,half the circumference will be so cut out1 the alternate divisions being left4 ,thus1 to turn four pieces1 each two inches wide1 a cylinder of sixteen inches will be required1 affording four grooves two inches wide1 and four intermediate pieces forming the partitions between the grooves4 ,the latter must1 by means of the saw and chisel or other tools1 be made to receive the strips exactly1 and the ends of the latter being carefully squared off1 are to be made to rest against the plate ,c1 ,fig4 #bjf1 which is cut out and screwed against the shoulder1 after the above-mentioned grooves have been cut4 ,the whole are then secured by two rings1 with screws4 ,probably the stoutest india-rubber rings now made would answer as well as the iron clamps in ,bergeron's description4 ,lay the strips in their places1 but as they are flat they will not form part of the cylindrical surface1 but will lie lower1 as ,fig4 #bjg1 or higher1 ,fig4 #bjh2 the latter is the best1 and the pieces may1 for this cause1 be cut out a trifle deeper than ultimately required and they may be planed down a little to remove the angles and assimilate them to the cylindrical surface4 ,the whole may then be turned together so as to form a plain cylinder1 the clamping rings1 ,fig4 #bji1 being shifted when requisite4 ,the whole is now to be formed into a balustrade1 but as the proportions of the mouldings of such a large cylinder would not suit the small pieces1 the hollows must be less deep1 and the raised parts less prominent than they would ordinarily be made4 ,the clamps are now to be loosened1 and the pieces reinserted with another face upwards1 the flange or plate against which their ends rest forming a gauge or stop to ensure their position1 without which precaution the mouldings would not eventually meet at the angles4 ,in cutting a fresh side the utmost care is requisite1 for if the work on the original cylinder is cut by the tool1 it will be impossible to restore it1 and the work will be spoiled4 ,in replacing the strips1 let the finished part lie below1 so as to come first in contact with the tool1 by which the angle will be clean4 ,extra care is for this purpose required in cutting the last side4 ,it appears to the writer that another precaution should be taken which ,bergeron omits1 namely1 to arrange the mouldings so that certain parts are left of the original size of the wood1 in order to retain a certain number of points of contact with the sides of the grooves1 so that the strips shall not fall deeper into them than at first4 ,the extremities of the strips should certainly not be left smaller than the central portion1 or the pieces will rock on the latter while in process of being turned4 ,the two ends1 therefore1 should be allowed to retain their original triangular form1 forming base and capital of the pillar1 or the pattern may be so planned that1 after the extremities have been left as supports they may be cut off when the work is complete4 ,care must be taken1 in working as above1 to have the cylinders so large above the estimated size that the inner apices of the triangles do not nearly meet at the centre1 else the whole chuck would be very weak and split into triangular strips4 ,the lathe called a spoke-turning lathe would accomplish this kind of work in a far more easy and speedy manner4 ,the balustrade would have to be made by hand as a pattern1 and cast in metal1 and any number could be produced precisely similar4 ,the lathe in question is on the following principle3--,the frame carrying the tool 7a set of revolving gauges7 is made to oscillate backwards and forwards to and from the piece to be operated on4 ,this is accomplished by its having attached to it a roller or rubber working against the cast-iron pattern placed parallel to the work1 and below or one side of it4 ,the rubber and frame are kept against the pattern by a strong steel spring4 ,the cutters also travel in a direction parallel to the axis of the piece4 ,hence any elevated part of the pattern causes the tool to recede from the work in a corresponding degree1 and a hollow allows a nearer approach of the tool4 ,thus1 as the tool is carried by a screw slowly from end to end of the work1 it is made to advance and recede in exact correspondence with the form of the pattern4 ,an immense deal of work is done in this way1 such as balustrades1 spokes of wheels1 the long handles of the ,american felling axes1 and similar irregular forms4 #ad ,with the universal cutting frame this kind of work is much more readily accomplished4 ,illustration3 ,,fig4 #aih4 ,illustration3 ,,fig4 #aig4 ,illustration3 ,,fig4 #aiib4 ,illustration3 ,,fig4 #aii4 ,illustration3 ,,fig4 #bjj4 ,illustration3 ,,fig4 #bja4 ,illustration3 ,fig4 #bjc4 ,illustration3 ,fig4 #bjb4 ,illustration3 ,fig4 #bje4 ,illustration3 ,fig4 #bjf4 ,illustration3 ,fig4 #bji4 ,illustration3 ,fig4 #bjh4 ,illustration3 ,fig4 #bjg4 ,the principle1 indeed1 is not new1 as the rose engine is a similar tool1 and1 so long back as ,bergeron's time1 pattern plates were used giving any desired motion1 endlong or otherwise1 to the tool1 or1 which in effect is the same1 to the work to be operated on4 ,,turning ,,spheres4 ,we must now recur to the sphere of which we have already spoken4 ,the method previously given for producing it is not sufficiently accurate1 although a very close approximation can thus be made to the perfect figure4 ,it is probably impossible without special apparatus1 rendering the tool independent of the hand1 to turn out an absolutely correct sphere--indeed1 it is a sufficiently delicate operation1 even with the following or similar apparatus4 ,for ordinary purposes1 indeed1 where the object is simply to produce a croquet ball1 a spherical box1 or a globe to be afterwards covered with paper1 or any such work1 the plan already given will generally suffice1 and1 indeed1 is very extensively used4 ,some practised workmen1 too1 will1 without even the aid of ruled lines1 turn out spheres of average excellence by the eye alone1 aided by a template4 ,when1 however1 it is proposed to hollow out a sphere so as to leave a mere shell of #a_/h in4 or less1 and perhaps include a number of such shells one within the other1 and a star in the centre of all1 it evidently becomes necessary to work with greater accuracy1 and still more so with respect to billiard balls1 in which even the slight variation caused by increased temperature will seriously affect the result of the most skilful play1 and cause the very best players to fail4 ,the principle of the spherical rest is displayed by the diagram1 ,fig4 #baj4 ,illustration3 ,,fig4 #baj4 ,illustration3 ,,fig4 #baa4 ,a is the chuck carrying the ball to be turned1 of which ,c is the centre4 ,in a right line with the latter1 and below it1 is a pin fixed to a block between the bearers of the lathe1 and on this the arm1 ,d1 turns4 ,the latter carries a tool-holder in which a pointed tool1 ,e1 is fixed4 ,the point of this tool will evidently move in a circle1 when the arm is moved by means of the handle1 ,d2 and1 as the centre of the circle is exactly under that of the proposed sphere1 the latter will be correctly shaped when the lathe is put in motion4 ,fig4 #baa gives another view of the tool-holder4 ,it is essential that the point of the tool should be in a line with the centre of the lathe mandrel1 so that it shall act on a diametrical plane as it is carried round the work4 ,such is the principle upon which a practically useful tool for turning spheres has to be arranged4 ,the faults in the above simple machine are many4 ,in the first place no provision is here made for the advance of the tool towards the work4 ,in the second place the requisite firmness and stability cannot be obtained by merely causing the bar to revolve upon a centre-pin2 and thirdly1 as the tool post is fixed to the horizontal bar1 the diameter of the ball must be limited4 ,in point of fact1 therefore1 the above arrangement would not answer1 and it is only described in order to illustrate the principle of all inventions for the production of spheres in the lathe4 ,to give steadiness of action the pin forming the centre of motion is connected with a circular metal plate truly turned1 upon which a second similar plate works1 and to the latter is attached the tool-holding apparatus4 ,it is difficult to make choice of a circular or spherical rest so as to give it precedence1 since most of the patterns ordinarily made are good4 ,to obtain the requisite movement is1 indeed1 by no means a matter of difficulty2 and one or two adjustments in respect of the height and radius of the tool being provided1 a very simple apparatus will answer the purpose4 ,to commence with ,bergeron's1 which1 though venerable1 is by no means inefficient4 ,this is represented in ,figs4 #bab and #bac4 ,a1 ,b1 is the base1 the tenon1 ,b1 accurately fitted to slide between the bearers of the lathe1 the whole being held down as usual by the bolt and nut1 c4 ,the top part of the base is surmounted by the accurately faced plate #bad1 on which a side sectional view is given in ,fig4 #bae4 ,this is fastened to the base plate 7which1 in ,bergeron's description1 is of wood7 by four countersunk screws4 ,it is turned with a recess1 so that the outer part stands up in the form of a rim1 and from its centre rises a conical pin1 b1 the upper part of which is first octagonal1 and then rounded and tapped4 ,it is this strong pin which forms the centre of motion1 and it must stand with its axial line precisely in the centre of the lathe bed1 so that if the plate were slipped close to the poppet head this line would bisect the nose of the mandrel4 ,this is essential in all patterns of spherical slide rest4 ,upon the lower circular plate rests that represented in ,fig4 #baf1 ,a and ,b1 the latter being the sectional representation4 ,this plate is drilled in the lathe with a central hole1 the lower part conical to fit the pin in the base plate1 the upper part countersunk as in the figure1 to receive the octagonal part of the pin and the nut4 ,the projections a1 and b1 in ,b1 represent the projecting rim1 a1 in the ,fig4 #baf1 ,a1 and this is made to fit very nicely within the rim of the lower plate1 while the adjacent part1 c1 rests upon the rim itself4 ,the accuracy of these bearing surfaces is of the utmost importance1 ,it is evident that this arrangement is calculated to give great stability during the revolution of the upper part of the rest1 which is fixed securely to the plate last named4 ,this plate has a hollowed edge cut with a set of fine teeth to be acted on by the tangent1 screw ,d1 ,figs4 #bab1 #bac1 and shown in ,fig4 #bag on a larger scale4 ,the bearings of this screw are attached to the base plate1 and the screw is prevented from moving endwise by collars as usual4 ,illustration3 ,,fig4 #bab4 ,illustration3 ,,fig4 #bac4 ,illustration3 ,,fig4 #bad4 ,illustration3 ,,fig4 #bae4 ,illustration3 ,,fig4 #baf4 ,illustration3 ,,fig4 #bag4 ,illustration3 ,,fig4 #bah4 ,illustration3 ,,fig4 #bai4 ,illustration3 ,,fig4 #bbj4 ,on the upper surface of the top plate are fixed parallel bars chamfered beneath like those of a slide rest1 and between these the tool holder slides1 the advance of the latter being effected by a screw precisely as in the slide rest already described4 ,in the plan of this instrument1 as seen from above1 ,fig4 #bah1 ,a1 ,b1 are the bars4 ,the tool is seen in position at ,c1 the tangent at ,d4 ,a scale is attached to the sliding part of the tool holder for determining the size of the sphere4 ,the tool is again seen in position in #bai1 and detached in #bbj4 ,in ,bergeron's description of the above spherical slide rest the method of using the apparatus is thus described3--,commence by placing in a chuck a cylinder of some sound wood1 and reduce it to a convenient diameter1 which should be a little greater than that of the proposed ball4 ,with the gouge work down this1 and give it roughly the form of a ball attached to a cylindrical base4 ,this base serves to sustain the ball during the operation1 and the form of an inclined plane is to be given to it where it is attached to the ball1 as seen in the drawing1 to facilitate the passage of the tool4 ,after this preliminary work1 place the instrument on the lathe bed1 and cause the tool holder to advance by means of a screw 7the one attached to the lower slide1 not the tangent screw7 until1 reckoning from #j;in41 the starting point1 the index attached to the sliding part has travelled over the graduated divisions of the scale1 so as to denote the size of the ball in its present rough state4 ,then slide the instrument along the lathe bed1 until the tool1 accurately adjusted as to height1 just touches the ball at the quarter circle4 ,this will be better understood by the diagram ,fig4 #bba1 in which ,a1 ,b1 are the lathe bearers2 ,c1 the tool in position2 ,d1 the ball2 ,e1 the chuck or the base of the cylinder4 ,having previously determined the size of the finished ball1 the work may now be carefully begun by clamping the rest underneath the bed1 and making use of the tangent screw4 ,little by little the work is to be reduced1 taking care not to cut too near the base on which the ball is yet carried4 ,this base is to be cut away little by little as the tool comes round1 and at the last cut the ball will drop off finished1 and it is not to be further touched with sand paper or other material4 ,hence1 as it approaches the finish1 the tool must be delicately and steadily made to traverse1 so as to leave a finished surface as it advances4 ,bergeron adds certain precautions as follows3--,if the material is very rough from the gouge1 so that at any point the tool is likely to meet with such resistance as would endanger the work1 such part may be pared down again by using the machine as a common rest for gouge or chisel2 for the apparatus once arranged should not be altered nor the fixed tool shifted until the work is done4 ,the tool throughout is to be advanced very gently forward at each turn by means of the screw1 which causes the parallel movement1 and the tool is to be accurately adjusted so as to be exactly in a line with the centre of the mandrel2 it is also to be very keenly sharpened1 and even polished4 ,the first impression given by an inspection of the above figures is that the ball would be liable to drop off before it could be fairly severed by the tool4 ,the writer determined to test this objection personally4 ,he selected a piece of sycamore1 which is very fit for the purpose1 and useful as a kind of medium between hard and soft woods4 ,a ball was turned by hand from this material having a diameter of about two inches4 ,the neck by which it was held was retained of the size of a cedar pencil during the final shaping of the rest of the ball4 ,it was of course not thus reduced until the ball was nearly spherical4 ,gradually the neck was cut away until it was perhaps as small as the lead of a pencil1 yet still the ball retained its position1 and the final stroke cut it off truly and tolerably cleanly1 ,e1 #bab and #bac4 ,it is really astonishing how small a portion of sound wood will retain a ball so turned1 but the lathe should not be allowed to stop1 else the tendency to hang down or sag would overcome the sustaining power of the fibres4 ,bergeron states1 indeed1 plainly1 that the process answers satisfactorily1 and as a man of large experience his opinion is certainly reliable4 ,nevertheless1 since sand papering or after process is to be eschewed1 it does appear to the writer that the final cut would leave a minute portion untouched requiring to be afterwards removed4 ,not having one of the rests in question the writer's opinion is to be taken quantum valeat4 ,the spherical rest more commonly used is that represented in the ,handbook of ,turning1 since it is necessary not only that the machine should be efficient for turning a sphere1 but likewise applicable to the ornamentation of the same by the revolving cutter and other apparatus used in such processes4 ,this and some other forms will presently be described1 and also an ingenious adaptation of the ordinary slide rest by means of guide pieces or templets to work of this character4 ,a very good form of chuck for holding spheres during the operation of hollowing them out or forming stars or cubes within them will1 however1 be first introduced here as described by ,bergeron4 ,it will be at once seen how simply and efficiently a ball can be thus held during such processes4 ,illustration3 ,,fig4 #bba4 ,fig4 #bbb represents a chuck for holding balls1 ,a being a sectional view1 ,b an elevation4 ,in the first1 b1 b1 represents the body of the chuck1 made as usual to screw on the mandrel4 ,at a1 the chuck is formed with a shoulder like an ordinary box4 ,this part of the chuck is to be hollowed out to fit the ball on which it is intended to operate4 ,on the side of the chuck at b1 is to be cut a screw of medium pitch4 ,mounting another piece of wood in the lathe a kind of cover1 c1 c1 is now to be made to fit over the body of the chuck like the cover of a box1 but hollowed out to the curvature of the ball4 ,a ring of brass or wood of section ,d being screwed on the inside to the pitch of the male screw on the outside of the chuck will hold the three separate parts of the apparatus firmly together4 ,let them be thus arranged and finished as one piece on the mandrel4 ,afterwards drill a hole in the centre of the part which forms the cover1 and enlarge it so that its diameter shall slightly exceed that of the openings necessary to be made in the ball for the purpose of hollowing out and forming within it stars1 or lesser spheres1 box1 cube1 or other design1 at pleasure4 ,in this chuck the ball will be held not only centrally but securely4 ,it is of course necessary to have a chuck specially made for each different sized ball1 but when it is considered that such things as these are merely turned as curiosities and to prove the capabilities of the workman1 it is not probable that more than two or three sizes of chuck will be needed1 and the difficulty of making them is not great nor the necessary expenditure of time1 either4 ,they should be made entirely of sound boxwood1 and so arranged as to the size of the respective parts that when the ball is inserted and the cover placed on1 the latter shall not quite reach the shoulder on the base of the chuck4 ,in the spherical rest of more modern times the principle of that already described is almost necessarily retained4 ,it is figured in #bbc4 ,the sole ,a is formed like that of an ordinary hand rest1 so that it can be advanced across the lathe bed1 and secured by the nut and screw underneath as usual4 ,from this rises a central circular plate1 which need not be more than a quarter of an inch thick1 but turned truly flat1 that it may be parallel with the surface of the lathe bed4 ,from this rises the conical central pin upon which works the plate ,b1 the edge of which is racked to be moved by the tangent screw ,c4 ,across this circular plate is securely fixed the chamfered frame ,d surmounted by the part ,e which carries the socket and tool receptacle1 the details of which will be entered into when describing the rest for ornamental work4#ae #ae ,the drawing shows a band at ,x encompassing the screw4 ,this is an error1 as the whole upper part1 including this screw1 is made to revolve by means of the tangent screw4 ,illustration3 ,,fig4 #bbb4 ,illustration3 ,,fig4 #bbc4 ,the method of turning from a pattern acting on the tool has been alluded to4 ,in some cases a similar method is pursued1 in which the hand supplies the place of automatic machinery1 an instance of this is the application of pattern plates or templets to the small slide rest now to be described1 by which not only parallel or spherical work may be done1 but the elevations and hollows in moulded work may be followed without difficulty4 ,the pattern plates can be made by the amateur or workman so that not only is no extra cost incurred1 but any desired form can be given to the work and as many duplicates made as may be requisite4 ,the simple slide rest itself is represented in ,fig4 #bbd4 ,the lower iron or steel frame is rectangular1 chamfered underneath1 and is cast with a projecting part ,b underneath to the socket of the hand rest4 ,there is1 therefore1 no sole or saddle required1 and the height is adjustable at pleasure to suit #c1 #d or #e-;inch centres4 ,c is a plate of brass1 cast with one ,v-piece similar to ,d1 the second ,e being removable at pleasure1 or both ,v-pieces or guide bars may be attached by screws4 ,they are attached by two or three screws passing through oval holes in the plate and tapped into the bar1 so that a little play to or fro is allowed1 by which they can be adjusted to grasp with more or less friction the iron bevelled frame4 ,they are kept up to their places by a pair of large headed screws tapped into the edge of the brass plate and marked e1 e1 in the drawing of the rest4 ,on the top of the brass plate is fixed in a like manner another pair of chamfered bars similar to those of a slide rest for metal1 but in the ornamental turning slide rests1 where lightness and accuracy are more needed than strength1 the parts are proportionally smaller4 ,the frame1 for example1 may be six inches or six and a half inches in length by two in width1 the brass plate two inches square1 or perhaps two and a half by two1 the longest measurement in the direction of the upper guide bars1 between which the tool receptacle will slide4 ,this will be quite large enough for a five-inch lathe1 although the measurement may be more or less if desired4 ,if taken as above1 the iron frame may be half an inch deep and the face of each side of similar size1 leaving one inch between1 in which the screw will lie4 #bbd ,b shows the under side of the frame with a cross piece to which the part1 ,b #bbd1 is attached4 ,the guide bars for the tool receptacle may be similarly small and light4 ,if the plate is #a_/d in4 thick and two in width the bars may be #c_/h in4 stuff before being bevelled1 the attaching screws can then be #a_/c in4 or #c_/af in4 in the shank1 the heads being large and flat1 and not countersunk4 ,it is probable that many amateurs would like to attempt such a rest themselves1 hence we have given the above details4 ,we must however1 warn them that as the above is for ornamental turning1 where accuracy is of the utmost importance1 great care must be exercised in the work1 and the various parts must be fitted to the utmost perfection4 ,the upper face of the lower frame must be quite level1 and the sides quite parallel1 and the upper or cross slide must be fitted precisely at right angles to it4 ,above all1 the screw by which the upper part is advanced in either direction requires great precision4 ,it should be made with a fine thread deeply cut1 and must fit its nut under the brass plate1 ,d1 without shake4 ,the nut itself should be long1 and must be carefully bored and tapped2 it should be also sawn through its length underneath1 to give it a spring1 so that it may grasp the screw tightly yet easily1 and this will also compensate for wear4 ,this will be understood when it is stated that the milled head by which the screw can be turned is graduated round its circumference1 as is also the face of the bed or lower frame of the rest4 ,hence to give the head a turn1 or half1 or a quarter turn1 must draw the sliding plate exactly the same distance to or fro1 at whatever part of the frame it may be at the time4 ,this necessitates all the threads being precisely alike4 ,we say precisely with a certain mental reservation1 for1 strictly speaking1 perfection is hardly possible1 and the skill and science brought to bear upon screw cutting when perfect work has been necessary1 as for astronomical instruments1 would hardly be credited1 so extremely difficult is this part of the mechanical art4 ,it would be better for the amateur to get the screw and nut cut by ,holtzapffel1 ,munro1 or other first-class maker1 who has the requisite means and can command the highest skill4 ,between the upper guide bars are fitted various tool receptacles4 ,the only one which need as yet be spoken of is that which holds the little inch-long tools for ordinary work or for use with the eccentric chuck4 ,this consists of a brass plate bevelled to fit the chamfered bars1 on the end of which is a small piece of steel with a rectangular hole and set screw1 as seen in the drawing marked ,x4 ,this plate has a tailpiece of rather thicker metal1 through which pass two set screws1 which regulate the depth of the cut to be made1 their points bearing against the end of the brass plate on which this tool receptacle works4 ,no screw is attached to move this upper slide1 but a wooden handle projects from it at right angles to be moved by hand1 or a lever ,y is made use of4 ,this has two projecting pins1 the front one taking one of the holes1 #a1 #b1 #c of the slide1 the other one of a set of similar holes in the top of the chamfered bars4 ,by this the slide can be advanced with ease and great steadiness4 ,we now come to the pattern plates or templets ,f1 alluded to4 ,these are formed of sheet iron about #a-bj in4 to #a-af in4 thick1 and must be long enough to reach from one end to the other of the iron frame ,a1 underneath which at each end are two holes a1 a41 ,fig4 #bbd ,b1 to receive screws by which the templets are attached by means of the slots1 b1 b4 ,the outer edge1 a1 of templet is the pattern to be copied4 ,the dotted lines in ,fig4 #bbd show a plate in position4 ,the tailpiece of the tool holder to be used has a projecting stud1 or is made with a screw with or without the roller seen at ,h1 and this is kept in contact with the templet by the hand or by a spring1 so that when the slide traverses the lower frame the tool-holder necessarily follows all the curves of the pattern plate4 ,an inspection of ,k will make it evident that the projecting screw must be so regulated as to length as to allow the tool-holder to go to the extremes of the projections and hollows4 ,it must therefore in the pattern shown be at least as long as the line a1 b1 ,fig4 ,k1 and a tool-holder of sufficient length must for similar reasons be selected1 or the tailpiece might touch the fixed plate on which it works before the guide pin had penetrated the deepest hollow of the pattern4 ,with these precautions nothing can exceed the ease with which this clever adaptation of the slide rest is made and used1 the greatest advantage being that the workman can make his own templets to any curve or series of curves that may be desired4 ,illustration3 ,,fig4 #bbd4 ,illustration3 ,,fig4 #bbd;,b4 ,at a later page is described a slide rest with the arrangements of the tool-holder somewhat improved1 and calculated for the reception of larger tools and apparatus4 ,the little rest here described is1 however1 very light and useful4 ,,hoblyn',s ,,compound ,,slide-,,rest4 ,a compound spherical slide-rest1 for ornamental turning lathes1 which has been patented by ,mr4 ,hoblyn1 ,rickling-green1 ,essex1 is capable of turning and ornamenting accurately spheres and any segments of circles convex or concave1 either on the surface or cylinder2 also1 it is stated that by the addition of templates any other curves1 not segments of circles1 can be turned out1 in addition to the work performed by an ordinary compound slide-rest4 ,in our illustrations1 ,fig4 #a is a side view1 and ,fig4 #b1 an elevation of the rest4 ,a is the lower1 and ,b the top plate1 ,c the carriage1 and the saddle as usual4 ,the lower plate1 of iron1 is planed on bottom and sides1 and has a longitudinal bevelled slot in the bottom to receive the fastening bolt1 so that the plate can be tightened up at any point on the lathe bed4 ,at one end of this bottom plate is a piece raised the whole of its breadth1 accurately turned and faced1 with a stout turned pin1 b1 for a pivot in the centre4 ,a wheel1 c1 is placed around this raised piece1 having any specified number of cogs1 and on its top any specified number of small holes drilled to receive two pins as segment stops4 ,the top plate is slightly narrower than the bottom one1 and has on its underside a corresponding surface to that raised on the plate ,a1 turned and faced with countersunk hole in the centre to fit on the pivot b1 on which it is tightened by a screw and washer4 ,the top of ,b is placed to receive two parallel bars of brass1 bevelled on the inner edge1 so as to form sliding bars for the carriage ,c1 one bar being a fixture1 the other capable of adjustment by tightening screws4 ,the sides are also accurately planed1 and on one a tangent screw1 e1 is so fixed as to be put in and out of gear with the brass wheel1 c1 for the purpose of driving the top plate round the pivot b4 ,in the raised surface of ,b1 is a countersunk slot forming a quarter circle1 with screw passing through it into the bottom plate2 by this means the top plate can be firmly fixed at any angle to the bottom plate for the purpose of slide-rest turning4 ,a small pointer1 f1 works clear of the brass wheel in the capacity of segment stop--two small pins being placed in the specified number of holes in c4 ,on the opposite side of the screw1 e1 on the top surface1 a screw1 g1 works in two standards screwed into the plate through slots in the bar1 which works through a traveller1 h1 firmly attached to the carriage1 ,c1 and therefore capable of driving the carriage in a rectilinear direction--for slide-rest purposes4 ,this carriage1 ,c1 consists of an iron plate i1 with standard k1 top plate l1 with parallel brass bars to receive tool receptacle m1 the bottom plate and standard being in one piece with the plate1 planed side and bottom1 so as to slide truly between the parallel bar on ,b4 ,the standard has its surface accurately turned with a pin in centre to form pivot4 ,the top plate is planed true1 bottom1 sides1 and top1 and has a countersunk hole in the exact centre1 so as to work on the pin1 and tightens up with a large nut4 ,in the plate is a countersunk slot forming a quarter-circle1 with screw passing through into the standard1 to set the tool receptacle either parallel with ,b for spherical turning1 at right angles to ,b for slide turning1 or at any angle for thick and thin cuts1 and similar patterns when used either as a spherical or slide rest4 ,the parallel bars are to be similar to those on ,b1 to enable the tool receptacle to be advanced or retired by screw or lever4 ,this part of the machine can be adjusted for height of centre thus3--,the standard k to be a hollow cylinder with fixing screw on one side2 the plate i to be made with turned pin on bottom1 to fit into standard2 elevating screw2 saddle as usual1 but with the addition of a small hole drilled in one of the sides1 and a corresponding one in the side of the lower plate ,a1 so placed that when a pin is fixed into these holes the pivot is exactly central to the lathe centre4 ,illustration3 ,,fig4 #a4 ,illustration3 ,,fig4 #b4 ,the way of using the spherical rest is thus described by ,mr4 ,hoblyn3--,when altogether1 and the point of tool adjusted by means of a square exactly over centre of pivot1 it is evident1 if the top plate moves round1 the point of the tool will still be in the same place2 but if we retire the point one half-inch1 on moving the plate right round it would describe an inch circle1 so that if the centre of pivot be exactly under the centre of the lathe1 and we move the rest the half-circle1 it will cut a perfect ball 7or any part of one1 if the cut be less than half a circle7 of such size as the distance doubled of point of tool from centre of pivot4 ,therefore1 by adjustment of the lower plate on the lathe bed according to the size of material 7this1 of course1 does not allude to the act of turning a ball1 when the centre of pivot must be exactly under centre of lathe71 adjustment of carriage from centre according to the size of circle required1 and adjustment of tool for depth of cut1 we are enabled to turn any convex curve4 ,to turn the concaves1 instead of retiring from centre of pivot1 it is only requisite to advance the point beyond the centre to the distance required1 when the same rules apply as to the convex curves4 ,in turning the concaves1 however1 it is necessary to turn the plates half-round1 so that ,a and ,b are in the same straight line1 instead of over each other4 ,this enables you to work on any sized piece of wood1 the object of the longitudinal slot in the lower plate being to enable you to adjust your previously arranged curve to any sized wood or ivory that your lathe will take1 less #b in41 the height of machine4 ,the desired curve having been turned1 take out the chisel1 and place in the receptacle any ornamenting instrument1 drill1 eccentric1 c42 advance the point till it touches the work1 then set your screw for depth of cut1 and work according to fancy4 ,whatever it is it must be mathematically correct on the curve1 as you have not altered it in any way4 ,you then remove your rest to cut the next desired curve1 and proceed as before4 ,the best way to execute a piece of work is first to make a sectional pattern of your design1 either by drawing or cutting it out with scissors from a double piece of paper1 when1 of course1 both sides come the same1 the line where the paper is doubled being the line of centre of lathe4 ,you can then1 with a pair of compasses1 ascertain with accuracy the necessary size of circle1 and the position of centre of pivot to procure the desired curves4 ,you may also produce a very good effect by a combination of two different curves in this way3--,let your ornamental instrument be the universal cutter2 working horizontally follow up your curve with it1 but1 instead of cutting right out on your curve1 let the instrument finish of itself in wood previously turned so as to fit its curve1 when you get the lesser and greater curves following in unbroken succession4 ,with the eccentric chuck numberless effects of the most curious description may be produced1 even work supposed to be only possible with a rose engine4 ,we believe the tool is to be seen at the shop of ,mr4 ,evans1 #ajd1 ,wardour-street4 ,to turn a sphere by means of a template attached to the slide rest as described1 the following adjustment of the rest and mode of proceeding should be followed4 ,a1 ,b1 ,fig4 #bbe1 is the chuck containing the material1 ,h1 to be worked into a sphere4 ,upon this the length1 or diameter 7equal to that of the template1 as will be explained71 is to be marked at ,k1 ,k1 which being divided equally by the line ,l1 ,l1 will give the dimensions of the ball as if it were about to be turned by hand4 ,the corners are to be turned off with the gouge1 as far as shown1 ,k being equal to e ,l1 and ,k f equal to ,k e4 ,the outline of the ball will with these measurements not be touched4 ,the angles left may also carefully be removed1 but 7as shown by the figure7 this operation must be conducted with great care4 ,a template must now be made containing a full semicircle1 every part of which can be traversed by the stud or screw upon the under part of the slide1 or the ball will not be severed by the final cut4 ,it is evident that the traverse of the slide during the operation will be the full radius of the ball1 and in this1 and indeed all cases of deep recesses1 and greatly projecting mouldings1 the ordinary tool-holder with tailpiece had better be removed1 and replaced with a slide like ,m1 having a pin straight through it to rest in contact with the template4 ,this will preclude the necessity for the long stud or screw spoken of before as necessary when the slide with the tailpiece is used1 but the tool cannot be advanced independently of the template as when the other form is used4 ,fix the rest so that when the top slide is at its central position the tool may stand as in the sketch exactly upon the central line of the ball4 ,take care that thus placed the tangent-pin of the slide is on the central mark of the template4 ,the long frame of the rest must likewise be parallel with the bed of the lathe1 keeping the top slide pressed against the template with the left hand1 while the top part traverses the frame under the action of the screw moved by the right hand1 the ball will be correctly cut4#af ,one or two cautions must1 however1 be given here1 to ensure a satisfactory result4 ,in the first place the cylinder from which the ball is to be made must be exactly of the diameter of the semicircle on the template4 ,h1 ,h is the cylinder to be turned to a sphere1 ,g1 ,g1 ,b shews the position of the tool at starting1 the dot on ,a1 the templet1 the tangent pin of the slide1 ,fig4 #bbf4 ,as the work proceeds the tool will take the several positions shown1 the dotted lines1 ,d1 being equal and parallel4 ,the tool will thus repeat the form of the template4 ,let the latter remain as before1 but let a smaller cylinder be inserted in the lathe1 or1 which is the same thing1 let the tool be now lengthened so as to start at ,c on the inner dotted line4 ,when the pin1 ,f1 has reached ,k1 which should be the axis of the ball1 the tool will be at ,m1 quite out of cut4 ,fig4 #bbg represents three forms of tool in contact with the ball at two points4 ,the first two will evidently be out of cut at the axial line1 as the side of these bevels will then touch the piece to be turned4 ,c is a form that will remain in contact from the diameter to the axial line4 ,the left side of the edge is slightly overhanging the side line of the tool1 ,d4 #af ,see ,appendix4 ,illustration3 ,,fig4 #bbe4 ,illustration3 ,,fig4 #bbf4 ,illustration3 ,,fig4 #bbg4 ,when the part shown has been cut this tool must be removed and a similar tool bevelled in the reverse direction1 adjusted by reference to the central line of the ball as before4#ag ,it is recommended to roughly shape the work with the gouge1 and partially to cut it off with the parting tool so as to relieve the tool as much as possible1 and when the last finishing cut is to be taken a freshly sharpened tool is to be made use of4 ,it is evident that in the above and similar work the rest may be placed across the end of the cylinder if preferred to turn the right hand hemisphere1 but it would have to be moved for the second half1 which should be avoided1 if possible4 ,the advantage which the circular rest has over the above is due to the fact that the tool and rest once in position1 neither has to be readjusted until the work is complete4 ,the slide rest and semicircular template forms1 however1 if judiciously used1 a very serviceable substitute and makes very satisfactory work4 ,whether or no the reader has a complete rest for spherical work1 he should decidedly provide templates to use as above4 ,they are not only useful for turning or ornamenting spheres1 but any forms whatever that may be desired1 and they possess this special advantage1 that when a dome or other pattern has been thus turned with a plain tool the same template used with revolving cutters will enable the work to be ornamented with perfect ease1 doing away in a great measure with the need of a dome chuck4 ,suppose1 again1 that a number of pieces are desired precisely similar1 as a set of pawns for a set of chessmen1 a sectional drawing made and transferred to a piece of sheet-iron1 and the latter cut to form a pattern plate1 will enable the most unskilful to work satisfactorily4 ,nothing more need be said of the uses of templates1 and for the present the subject will be dismissed1 though it may possibly be referred to again in a future page4 #ag ,holtzapffel uses a tool1 the plan of which is semicircular1 like a small round tool1 cutting on front and two side edges2 the tool is very narrow and bevelled below4 ,,chucks ,,with ,,slides ,,and ,,compound ,,movements4 ,the first of the chucks comprised under the above head is the oval or elliptical chuck1 and it is introduced first in order because it is not essentially a machine for ornamental turning1 as are the eccentric and others of this class4 ,there are many plain works required of elliptical section1 as bradawl and other tool handles1 for which a very simple arrangement is required4 ,the principle of the oval chuck is as follows3--,there is an arrangement of slide1 by which as the piece revolves it is drawn gradually further from the tool during half a revolution1 and in a similar manner caused to approach it during the remaining half revolution1 each point in the circumference alternately partaking of such movement2 the whole of these points together1 which1 of course1 form the circumference1 will become an ellipse4 ,let ,d1 ,fig4 #bbh1 be the centre of the mandrel1 ,a1 ,b the direction of the slide moving up and down in a right line1 and carrying the work upon a screw in the centre of it4 ,c1 ,e become centres1 and may be taken as the extremes1 for as the work revolves a succession of centres are formed and instantaneously changed4 ,the figure produced will be the oval shown4 ,to render this1 however1 clearer1 ,fig4 #bbi may be taken1 which represents the chuck in its most simple form with separate details of the parts which compose it4 ,a is the chuck with central slider and chamfered bars1 as described in speaking of the slide and rest and previous apparatus2 ,b is the slide detached2 ,d1 front view of the same4 ,the short arms a1 b1 pass through slots in the back plate as seen at ,c1 which shows this plate with slide removed4 ,through these short arms pass a pair of adjusting screws2 or still better a and b are themselves cross arms or pallets extending the width of the plate as seen next drawing1 and in the chuck of ,muir which follows4 ,they are merely flat plates of steel embracing the guide ring1 so that some point in their inner surface may rest against it during every part of the revolution of the chuck4 ,illustration3 ,,fig4 #bbh4 ,illustration3 ,,fig4 #bbi4 ,the guide ring here alluded to is shown at ,e1 and also at ,g1 fixed in its place upon the poppet4 ,it is in the form of a raised ring with arms1 ,b1 ,c41 which are turned at right angles near their ends1 and through which pass adjusting screws with conical points4 ,this plate is flat at the back and bears against the face of the poppet1 the mandrel nose falling into the central opening ,e4 ,it is kept in place by the points of the screws falling into conical holes at the sides of the poppet head4 ,at ,f is a side sectional view of this plate1 with its raised and accurately turned ring1 ,h1 and at ,g is seen the poppet with the plate attached1 the left arm being dotted to show the position of the adjusting screw4 ,it is this ring and plate which regulate the movement of the slider1 and1 with it1 of the work1 the latter being attached to the screw in the centre of the sliding plate1 which screw is a counterpart of that upon the nose of the mandrel4 ,suppose the chuck ,a screwed to the mandrel1 and the ring accurately concentric with the mandrel1 in which position1 the pallets must touch at two opposite points4 ,in the best chucks there is an adjusting screw to each1 by which the contact can be regulated4 ,in this position any object of a circular form can be turned1 for the slider remains in one position1 and its screw1 upon which the work is fixed1 is a continuation of the mandrel4 ,but if now the adjusting screws of the part ,e are turned1 the one being loosened and the other tightened1 the guide ring will no longer be concentric with the mandrel1 and1 as the screws of the slider bear upon it1 the slider will during its revolution be moved to and fro to a distance regulated by the eccentricity of the guide ring4 ,the combination of this circular motion of the chuck and rectilineal movement of the slider will produce an ellipse1 and a stationary tool applied to the work will cut it1 into that form4 ,the above simple arrangement of oval chuck suffices only for plain work4 ,the only figures that can be described by its means1 upon the cover of a box1 for instance1 being a series of ellipses of which the longest diameters fall in the same right line1 and of which the centres are coincident with the axis of the mandrel1 as ,fig4 #bbi4 ,illustration3 ,,fig4 #bbi4 ,even these1 however1 cannot be done without some compensating arrangement1 as the minor axis does not diminish in length at the same rate as the major--hence the ellipses get narrower and narrower until the central one becomes a mere right line4 ,this is referred to again in the ornamental section of this work4 ,illustration3 ,,fig4 #bca4 ,illustration3 ,,fig4 #bcb4 ,illustration3 ,,fig4 #bcc4 ,illustration3 ,,fig4 #bcd4 ,illustration ,combinations like #bca1 in which the ellipses intersect1 cannot be so obtained4 ,hence the oval chuck is provided with a wheel1 either racked to work by a tangent screw or fitted with a spring catch1 by which it becomes a dividing plate4 ,this wheel revolves on a central pin#ah fixed to the middle of the sliding plate1 and carries a screw of the same pitch as that upon the mandrel to which other chucks can be attached4 ,by this means the axial lines of the ellipse can be varied in direction4 ,this addition is shown in ,fig4 #bcb1 which is a section1 and #bcc1 which is a front view4 ,in the former1 ,a is the wheel1 which1 as previously explained1 should be so arranged as to contain a number of cogs divisible by as many figures as possible2 #if is such a number1 being divisible by #b1 #c1 #d1 #f1 #h1 #ab2 #gb is also a good number1 as it will divide by #b1 #c1 #d1 #f1 #h1 #i4 ,if the edge is racked and moved by a tangent-screw with divided head a greater range can be taken and finer work done4 ,in this case the face of the wheel can be marked with divisions1 and a fine steel pointer1 as shown at ,f1 added to count by4 ,the pin ,b1 which is firmly attached to the centre of the slider plate1 must be strong1 and the lower part at least should be conical4 ,it is drilled and tapped at the smallest end1 and when the circular plate with its screw is slipped upon it1 a screw1 ,e1 the head of which is countersunk into the face of the large screw1 retains it in place4 ,the slide1 ,c1 has a recess turned to fit the wheel plate1 and the latter is cut as shown at ,x1 which ensures a more accurate bearing than if it was left flat on the lower surface4 ,in making this chuck certain precautions are necessary4 ,in the first place1 the guide ring fixed to the poppet must be exactly concentric with the mandrel when in its central position2 and when it is drawn by the adjusting screws to the right or left the central line must remain parallel with the surface of the lathe bed4 ,to ensure this centrality it is necessary to turn its outer surface when it is in position on the lathe head4 ,so at least says ,bergeron2 and it is perhaps the best method whereby to ensure the accuracy that is required4#ai ,for this purpose ,bergeron directs the use of a cutter similar to ,fig4 #bcd attached to the mandrel as a chuck1 the edge which is on the inside of the bent part at a acting on the exterior of the ring as the mandrel revolves4 ,the screws allow the tool to be advanced closer to the ring as the work proceeds1 while they secure it at any desired point4 ,such a contrivance as this1 used merely as a finishing tool to correct any slight error1 is no doubt sufficiently satisfactory4 ,the various parts of this and other compound chucks should be first turned separately to near the required size1 and accurately finished when in their respective places upon the chuck4 ,any parts which present a difficulty from the impossibility of retaining them in place while operated upon1 may be soldered with tinman's solder1 and thus turned1 after which the application of moderate heat will detach them1 and the fluid solder can at the same time be wiped off with a pledget of tow or cotton waste4 ,as many of our readers may wish to make such apparatus as the above1 it may be desirable to add a few directions for the preparation of chamfered edges such as those of the slide and guide bars1 the latter of which should be of iron or steel4 ,let the slide1 for instance1 be cast as a rectangular plate and the two flat surfaces be roughly levelled with a file4 ,one of these must now be made perfectly true1 either by mounting it with solder upon the face plate of the lathe1 and levelling it with the aid of the slide rest1 which is perhaps the safest plan1 or by careful working with the file1 using a straight-edge in all directions1 and finishing by careful grinding upon a flat stone slab with water1 or on a wooden grinder charged with emery and oil4 ,after one side is finished1 the opposite face may be similarly treated2 but for this the plate may be secured to the finished surface of the lower plate of the chuck itself1 and turned with a tool fixed in the slide rest4 ,the edges must now be filed truly at right angles to the sides1 care being taken to keep the long sides of the plate parallel4 7,the short sides or ends will be rounded by being turned true with the edge of the chuck47 ,the work must now be tested with the straight-edge and small steel square1 and any error carefully corrected4 ,of course1 if the reader is the happy possessor of a planing machine1 all these operations will be facilitated and accuracy more likely to be ensured4 ,it may here be mentioned that1 to supply the want of such planing machine 7a want often felt by amateurs who have not mastered the use of file and scraper71 ,monro1 of ,gibson-street1 has cleverly added a planing apparatus to the ordinary foot lathe1 rendering the latter tool complete for all purposes of amateur engineering4 #ah ,this pin should have been shown of a conical not cylindrical form1 and much stronger in proportion4 #ai ,this part is always so turned by the best makers4 ,this handy apparatus will be found on a later page fully described and illustrated by a photograph of the machine4 ,the writer has seen it and used it1 and can testify to its satisfactory working1 as a lathe thus fitted does not run heavier or require greater exertion than when used for ordinary turning4 ,the next step will be the chamfering of the edges of the plate4 ,let #bce represent the plate in its present condition1 with rectangular edges4 ,to produce a chamfer of #de1 draw a line1 a1 b1 at a distance from the edge equal to the thickness of the piece4 ,if a smaller angle is desired1 the line must be drawn further back4 ,an angle of #cj to #ce1 is1 in the writer's opinion1 better than one of #de1 as the chamfered bars will then have a wider bearing on the upper surface of the plate1 tending to hold it more securely down upon the lower part of the chuck4 ,nothing remains but to file carefully down from the line thus drawn to the lower edge1 by no means a difficult operation if care is exercised not to obliterate the mark1 or to trespass the least beyond the assigned limit4 ,a template1 cut like ,fig4 #bcf1 of the desired angle1 will be a gauge for the edges of the plate1 as well as for those of the chamfered bars1 and will serve to make assurance doubly sure4 ,the arms which stand out at the back of the slider to embrace the guide ring are not fastened to the plate immovably1 but with power of adjustment4 ,a pair of short slots are made in the slider1 into which a square projection from the arms fits1 and the whole is clamped by a screw1 as shown in #bcg1 ,a1 ,b1 and ,c4 ,illustration3 ,,fig4 #bce4 ,illustration3 ,,fig4 #bcf4 ,illustration3 ,,fig4 #bcg4 ,a more accurate method is shown in the ,ornamental ,section for finer adjustment than can be secured in this way1 but for a home made chuck the above will suffice and is the easiest plan to carry into effect4 ,to use this chuck1 the guide is first arranged1 so that its ring is concentric with the mandrel4 ,a mark is generally made upon it1 and also upon the lathe-head1 by which this position can be readily insured4 ,the chuck is then screwed upon the mandrel1 and the arms adjusted1 as just described1 so as to embrace accurately1 but not too tightly1 the guide ring4 ,they are then1 once for all1 fixed in that position by the screws alluded to4 ,a few drops of oil are necessary to lubricate their inner surface and the exterior of the guide1 and the latter being withdrawn by its adjusting screws to the desired eccentricity1 the work may be proceeded with4 ,a rough piece of wood1 however1 should always be first turned to a cylindrical form1 as an oval chuck being an expensive article is to be carefully preserved1 and not exposed to the shocks inseparable from the process of roughing down the work4 ,moreover1 there should always be one or two screws passing through the slider into the back plate1 to take away the strain from the chamfered bars1 which can be removed when the slider is to be brought into action4 ,two precautions are here laid down respecting oval turning1 which1 in all probability1 a tyro would not suspect to be necessary until taught by failure4 ,in the first place1 at whatever point of the circumference the tool is held1 at that point it must remain1 or rather1 it must remain in the same horizontal line1 being neither raised nor depressed4 ,hence1 for all work where accuracy is needed1 oval turning should be done with the slide rest4 ,in the second place1 when it is desired to place a succession of ellipses one within the other on the face of the work1 like ,fig4 #bbi1 it will not be sufficient to place the tool nearer to the centre for each ring1 but the eccentricity of the guide ring must be reduced at the same time2 otherwise1 when the middle is reached1 a straight line will be the result1 instead of the proposed ellipse1 as already stated4 ,the lathe should not be driven at a very high speed1 and the moving parts should be lubricated from time to time4 ,there are other ways of compensating the error produced by the oval chuck1 or elliptic cutting frame1 which however are so entirely connected with ornamental turning that they are reserved to be introduced into that section4 ,a contrivance for turning ovals invented1 and communicated to the ,english ,mechanic by a ,suffolk amateur1 deserves a place here4 ,it is thus described by the inventor3-- ,,turning ,,ovals1 ,,etc41 ,,by ,,means ,,of ,a ,,template4 ,ovals are generally turned by causing the work to move in and under guidance of an oval chuck4 ,illustration3 ,,fig4 #bch4 ,there seems no reason why the same result should not be arrived at by communicating a movement to the rest supporting the cutting tool in the following manner3--,let ,a1 ,a1 be lathe bearers1 ,b1 pulley1 ,c1 screw of mandrel1 ,d1 template fixed thereon1 ,e1 friction wheel on the end of bar ,f1 ,g rest 7a board of any convenient width7 moving on pivots at ,h4 ,the friction roller1 ,e1 is to be kept in contact with the template by the cord running over the pulley ,t1 stretched by the weight ,l4 ,the rest will thus oscillate under the guidance of the template1 which may be either oval or rose engine pattern1 and the cutting tool form the pattern of the template used4 ,there might be other modes of causing the rest to oscillate on the same principle4 ,the lathe would require a slow motion1 the same as with an oscillating mandrel4 ,,eccentric ,,chuck4 ,illustration3 ,,fig4 #bci ,next in order of the compound chucks stands the eccentric1 the use of which is not entirely confined to mere ornamentation1 as it is often very convenient to the turner to have the power of shifting the centre of his work4 ,thus1 a solitaire board may be drilled with the necessary cup-shaped holes1 or any work of a similar character completed by the help of this chuck without the necessity for constant re-centering4 ,the general work of the chuck in question is nevertheless ornamentation1 for which it is peculiarly adapted either alone or in combination with other compound chucks1 or overhead apparatus4 ,the sliding plate of this chuck works between chamfered steel bars1 the same as in the oval chuck4 ,there is1 however1 no guide ring on the lathe head to regulate the movement of the slide1 and therefore also no necessity for the projecting arms at the back4 ,the slide1 in fact1 is moved by a screw with a graduated head1 similar to those already described4 ,fig4 #bci represents the common form of this chuck1 in which the wheel which forms a dividing plate is moved by a tangent screw4 ,the sliding plate is shown slightly drawn out by its screw1 the degree to which it is moved being that of its required eccentricity4 ,when the plate is drawn back to correspond with the base plate1 the centre will be in a line with that of the mandrel1 and any work turned upon the chuck in this position of the slide will be cylindrical4 ,the central screw of all these compound chucks being alike and of the pitch of that on the mandrel1 any of the ordinary cup chucks can be used with them to hold the work2 or the eccentric chuck can be screwed to the elliptic1 cycloidal1 or any other in the set1 by which means an endless variety of curves can be described4 ,the effect produced by the simple eccentric chuck now described is as follows1 the slide rest being used with it as a matter of course4 ,let a piece of box or other wood be fixed by means of a cup or other chuck upon the screw of the eccentric chuck1 and the slide rest with a single point tool be brought in front of it4 ,by means of this the work must be carefully faced1 and made uniformly level4 ,a ring ,a1 ,fig4 #bdj1 may now be cut1 which will be concentric with the mandrel4 ,the slide of the chuck being now drawn down by a few turns of the leading screw 7the tool and rest being kept in its original position71 the centre of the work will thereby be shifted1 and the tool being advanced to touch the same1 the circle ,b will be formed of the same size as the first1 but necessarily cutting it at two points4 ,another turn of the screw will enable ,c1 and similarly ,d1 or any number of circles to be successively formed4 ,the centres of these circles will be in a line across the face of the work4 ,the ratchet wheel is added to enable the turner to arrange his circles round a common centre1 instead of being thus obliged to keep them in a right line1 and it will presently be seen what a beautiful variety of interlaced circles can thus be accomplished4 ,the dividing wheel is1 as previously explained1 divided on its edge into an equal number of teeth1 or racked for a tangent screw and divided on the face and edge4 ,we shall suppose the number of divisions to be #abj4 ,face the work afresh1 and1 drawing back the slide until the centre is concentric with the mandrel1 as at first1 cut a boundary circle1 ,a1 ,fig4 #bda4 ,move the slide of the chuck a few turns1 as before1 and cut an eccentric circle4 ,now move the dividing wheel thirty teeth1 and cut a second1 and1 advancing by thirty each time1 cut a third and fourth1 and ,fig4 #bda will be the result2 the centres of the eccentric circles falling upon four points of the inner dotted circle1 which is itself concentric with that first made4 ,illustration3 ,,fig4 #bdj4 ,illustration3 ,,fig4 #bda4 ,illustration3 ,,fig4 #bdb4 ,illustration3 ,,fig4 #bdc4 ,if the same process is followed1 but the number of the circles increased1 a very neat snake-like ring will be formed1 constituting a border1 in the inside of which other combinations may be made4 ,in ,fig4 #bdb1 twelve interlacing circles are shown2 in ,fig4 #bdc1 twelve circles1 described upon centres1 which lie upon the circumference of a central circle of equal size4 ,this last pattern1 when more finely executed1 by doubling or trebling the number of eccentric circles1 forms the device generally cut upon watch cases1 under the name of engine-turned4 ,the best way to try patterns1 is to cover the face of a piece of boxwood with paper1 using a pencil in the tool-holder of a slide rest instead of a cutting tool4 ,if a softer disc is used instead of box1 round pieces of paper or thin card can be fixed upon it with ordinary drawing pins2 and if the first pattern is unsatisfactory1 a second1 and any successive number of pieces1 can be mounted1 and fresh patterns traced by the same means4 ,it would be mere waste of time to multiply specimens of the patterns that may be executed by the aid of the chuck just described2 and1 indeed1 this could only be done by cutting in the lathe itself the blocks from which such specimens must be printed4 ,for the present1 at any rate1 the principles only by which such devices may be executed will be given 7as above17 and the designs will be left to exercise the ingenuity and taste of the reader4 ,it happens1 moreover1 that few as are the works devoted to the general principles and practice of plain turning1 more than one has been published on ornamentation by the eccentric and other compound chucks1 in which a variety of executed patterns appear1 of more or less beauty2 and in the ,english ,mechanic has lately been printed a selection of exquisite designs by ,mr4 ,g4 ,plant1 whose chuck1 indeed 7to be presently noticed71 bids fair to supplant the most simple one now described4 ,the chief recommendation1 perhaps1 in the latter1 is its great simplicity1 as it may be made by any amateur sufficiently practised in the use of tools2 whereas the geometric chuck is too complicated to permit this4 ,it will be observed1 on inspecting the drawing1 ,fig4 #bci1 that the divisions on the face of the wheel are continued on the side above the part that is racked2 this permits them to be seen when the piece of work overlaps the circle of the wheel4 ,the steel point shown at ,b1 answers as an index1 either to the surface marks1 or to those on the side4 ,the tangent screw is now generally fitted in a small frame1 which is itself pinned at one end to the top plate1 and kept up to the dividing wheel by an eccentric cam4 ,this is not shown in the drawing2 the plan is nevertheless good1 as the screw is instantaneously released from gear at pleasure1 when the wheel may be turned by hand to any desired position2 after which a slight movement of the cam brings up the screw1 and all is made ready for work4 ,the eccentric chuck becomes available for such work as shown in ,fig4 #bdd1 representing the bottom of a candlestick1 ringstand1 or similar article4 ,in this case the centres of the eccentric work 7now cut quite through7 are on the circumference of a circle larger than1 and outside1 the work itself4 ,instead of cutting through the whole thickness of the stuff the outer circle may remain such1 and the blackened part may represent an inner raised surface1 when the contrast formed by the sharp edges round the pattern with the smooth circular part will be very agreeable to the eye4 ,to improve still more this design1 the outer part may be ebony nicely moulded and edged with ivory1 and the raised part ivory2 or the same may be alternations of ebony and holly1 which will form a contrast almost equally agreeable4 ,a small chisel-ended tool must be made for this work if the whole is in one block1 as it will be necessary to leave a level surface upon the face of the lower part4 ,there are an infinite number of designs of similar nature1 which will occur to the reader when the principles of the chuck have been mastered1 some of which would at first sight appear to have been worked by other means4 ,fig4 #bde1 for instance1 which is but a modification of the last1 scarcely looks like lathe work1 but can be cut more rapidly this way than any other--of course the fret saw will do similar work1 but it would first have to be marked out1 and afterwards the marks of the saw teeth removed1 whereas the above is cut and polished at once4 ,it may here be observed that the eccentric chuck itself is used to fix the position of the various circles to be cut1 whereas the size of these circles is determined by the slide rest4 ,thus in ,fig4 #bdf1 while the centre of the chuck is concentric with the mandrel1 bring up the tool in the rest and cut the circle ,f1 ,g1 ,h1 of which ,b is the centre2 draw down the slide of the chuck until its centre is at ,c1 leaving the slide rest as it is1 and the circle ,f1 ,e1 ,d1 will be formed of equal size with the first4 ,now move the screw of the slide rest so as to draw in the tool towards the centre of the lathe bed without altering the chuck1 and the small circle will be the result1 whose centre 7being dependent on the chuck alone7 is the same as that of the larger circle4 ,bearing in mind this principle1 that the chuck determines the various centres only1 and the slide rest the radii1 little difficulty will be experienced in devising and executing designs4 ,such is the simple eccentric chuck1 of which the use is tolerably extensive2 but there are1 nevertheless1 certain positions in which the eccentric designs are required1 which cannot readily be obtained by its means4 ,fig4 #bdg is one of these1 in which a moment's inspection will show the necessity of two distinct movements of the slide at right angles to each other4 ,hence a second slide is attached to the first at right angles1 much the same in effect as a second chuck screwed upon the first but standing across it4 ,this is the compound eccentric chuck to be subsequently described in detail4 ,there is one drawback to the use of these chucks1 namely--their excessive weight1 which causes a great deal of vibration in the lathe itself1 especially when the eccentricity of the slide or slides is great4 ,an accidental blow moreover from the chuck under the above condition would be very severe4 ,hence the various cutters eccentric and others1 worked by the overhead apparatus already in part described are infinitely more pleasant to use and even more effective and more easily managed4 ,the eccentric chuck can be used in combination with these1 and the capabilities of the two will thus be vastly extended1 but in this case the chuck is kept stationary while motion is given to the tool1 and the defect just alluded to no longer exists4 ,in cutting patterns upon hard wood and ivory a common defect is shallowness of work1 the cuts should not be so light as to give merely an effect of a design scratched upon the surface4 ,the cut should be deep and clean1 and the tool not only sharpened but polished so as to leave the device boldly executed1 the small triangular and other shaped pieces left between the cuts standing up clear and solid4 ,some patterns1 as the shell1 which will be presently spoken of1 require to be deep at one part and shallow at another4 ,some devices look best when cut with a point tool with double and others with single bevel to the edge1 and the same design worked with different tools will appear almost like two distinct patterns4 ,illustration3 ,,fig4 #bdd4 ,illustration3 ,,fig4 #bde4 ,illustration3 ,,fig4 #bdf4 ,illustration3 ,,fig4 #bdg4 ,illustration3 ,,fig4 #bdh4 ,the double eccentric is represented in ,fig4 #bdh4 ,the part ,a is the foundation plate1 with a projection at the back1 tapped to fit the mandrel4 ,b1 ,b1 the lower guide bars2 ,k1 ,k1 the lower sliding plate4 ,all the above parts are precisely similar to those of the simple eccentric chuck4 ,upon the face of this lower slide are attached two chamfered guides1 ,c1 ,c1 at right angles to the first4 ,they are kept in place by screws passing through oval holes on their faces1 and tightened when required by screws1 tapped into four little square blocks1 ,d1 ,d4 ,between these guides slides the upper plate1 which carries the screw for chucks1 and the dividing wheel as before worked by a tangent screw1 ,g2 to either end of which a key is fitted4 ,the leading screws1 ,e and ,f1 which move the two slides1 have squared ends projecting both ways1 so that the plates can be made to work eccentrically in either direction1 which is sometimes an advantage4 ,the chucks do not screw down upon the face of the division plate1 on account of their projecting parts at the back2 and very commonly a round plate1 ,o1 somewhat smaller than the wheel and about #a_/d in4 thick is attached to the face of the latter to raise the work still higher1 so that the dividing plate can be readily seen4 ,the more compactly1 however1 the parts of this chuck are made1 and the less the work projects from its face the better2 as there will be the less strain upon the central pin1 and upon the plates and their guide bars when the tools are applied to the work4 ,to be able thus to place in the centre of rotation any given point in a piece of work1 whatever may be the form of its boundary lines1 is of immeasurable advantage1 even though the capabilities of this chuck are confined to objects of plane superficies1 it being impossible to reach by its means the side of a cylinder1 or the surface of a sphere or spheroid4 ,it is evident that any line upon the face of a box1 for instance1 whether the latter be square1 round1 octagonal1 or of any other form1 may be followed with two movements of the slides1 combined with the rotatory movement of the dividing wheel4 ,thus1 a border of interlacing circles may be carried round the edge of such a box1 ,fig4 #bdh2 or1 a series of such circles forming constantly diminishing octagons1 hexagons1 squares1 c41 may be thus readily executed4 ,nevertheless1 what was said of the simple eccentric chuck1 applies with even greater force to the compound eccentric4 ,it is a heavy piece of apparatus1 requiring a lathe with substantial poppets and bed2 the whole well braced to the floor and wall1 to withstand the excessive vibration caused by the revolution of the apparatus4 ,it was1 indeed1 in view of this and similar appliances that we insisted in our initiatory paper upon the great importance to the workman1 of adequate strength and solidity in the various parts of the lathe itself4 ,in ,fig4 #bdi1 we give a simple specimen of work to be executed by the compound eccentric chuck4 ,illustration3 ,,fig4 #bdi4 ,illustration3 ,,fig4 #bej4 ,the compound geometric chuck of ,ibbetson1 manufactured by ,holtzapffel and ,co41 is a double eccentric considerably improved and of very extensive application4 ,a full description of it is published in a book written by the inventor1 in which an immense number of patterns executed by its means is given with detailed directions for their execution4 ,as these patterns are almost essential to a description of the apparatus as exemplifying the working of its several parts1 the reader is referred to the book in question1 or to a translation of it into ,french in the supplement to ,bergeron's work4 ,to enable the turner to execute patterns on the side of cylindrical pieces a chuck is used called a dome chuck1 similar to ,fig4 #bej4 ,a rectangular frame of brass1 ,a1 carries a sliding plate ,c1 at right angles to it1 the latter having a tailpiece which fits accurately between the frame1 and is tapped to receive the finely cut leading screw with divided head1 ,b4 ,a nut at the back of the frame clamps the slide in any desired position4 ,upon the upper face of the latter is a wheel racked on the edge so as to be moved by the tangent screw1 ,e4 ,this wheel1 like that of the oval and eccentric chucks1 turns on a strong conical central pin1 and has a screw attached of the same pitch as that on the mandrel4 ,the chuck is screwed to the mandrel by the projecting flange1 ,f4 ,the work is thus mounted at right angles to its ordinary position4 ,by this arrangement any point in the side of a cylinder can be brought in contact with a tool fixed in the slide rest1 and by means of the graduated screw heads of the latter and of the chuck various devices can be accurately made4 ,this chuck may be used alone or in combination with the eccentric1 and the quick revolution of such cumbrous pieces that would be a great drawback to their use is less frequently required1 now that the following apparatus has been added to the lathe1 and eccentric revolving cutters1 with drills and other tools1 have taken the place of heavier and more inconvenient apparatus4 ,it is indeed much more convenient in the majority of cases to keep the work itself fixed1 and to operate upon it by tools put in rapid motion1 because the latter1 from their excessive velocity compared with that which can be conveniently given to the material1 make better work1 and at the same time from their lightness impart no tremor to the lathe while in motion4 ,the cuts thus made are in consequence very clean and smooth1 and free from those slight undulations apparent when any vibration takes place in the lathe itself4 ,the different varieties of overhead apparatus have been already described and illustrated1 and it only remains to describe more in detail the revolving cutter frame1 drills1 and other apparatus used therewith4 ,the following pieces fit into the top of the slide rest in what is called the tool receptacle1 and are advanced to the work by means of a lever as already described4 ,fig4 #bea is the revolving cutter frame1 the spindle of which is put in rapid motion by a cord from the flywheel passing to the small pulley through the medium of the overhead apparatus1 as shown in a previous page4 ,for the purpose of cutting small intersecting circles1 a forked drill1 ,fig4 #beb1 or a crank formed drill1 #bec1 will suffice1 and if these are made to cut deeply the result will be a succession of hemispherical knobs or beads 7these must not intersect74 ,a drill like ,fig4 #bed will give a knob raised in steps1 and it is plain that by cutting the end of the drill to a section of the required moulding the latter may be rapidly executed4 ,the flat inch long cutters used with the geometrical chucks 7when the work revolves instead of the tool7 are1 of course1 made of a variety of forms upon the same principle4 ,cases of these drills and cutters beautifully finished are sold by all the leading dealers in turning lathes and apparatus4 ,it is essential that these tools be kept very sharp1 and that their cutting edges should be polished if first-class work is to be done4 ,the difference in the appearance of execution is very evident when the cutter is thus perfect1 as every cut bears a high polish1 which cannot otherwise be imparted4 ,nothing can be applied to finish eccentric work except friction with a hard brush1 and even this is much better avoided1 as rubbing of any kind tends to round edges which should be kept sharp and to obliterate the finer and more delicate lines4 ,it is likewise the best plan to finish with any particular tool all the work to be done by it without removing it from the tool holder for the purpose of sharpening4 ,if1 however1 this is necessary the following contrivance must be used to insure the precise form which the cutter had at the commencement of the work4 ,this being likewise necessary with respect to the fixed tools for ornamentation1 the apparatus requisite in either case will be introduced here1 the drawings and description being extracted from ,holtzapffel's valuable work already alluded to4 ,illustration3 ,,fig4 #bea4 ,illustration3 ,,fig4 #beb4 ,illustration3 ,,fig4 #bec4 ,illustration3 ,,fig4 #bed4 ,fig4 #bee is arranged for flat tools of various angles1 or drills with single joints4 ,a1 is the stand of brass1 with two turned and hardened steel legs4 ,to this is hinged at ,g1 by a screw joint1 the part ,k1 the upper part of which forms a semicircular arc1 ,c4 ,a second arc1 ,b is fixed at one end to the stand ,a1 and passes stiffly through a mortise at the top of ,k4 ,the latter can be raised1 therefore or lowered at pleasure upon this second graduated arc1 and clamped at any angle by the screw ,h4 ,to the lower part of ,k is pivotted the tool holder1 ,d1 the upper part of which is pointed1 and screws as an index upon the arc ,c1 showing the angle at which it is placed4 ,this tool holder is clamped by a nut at the back1 which fits the end of a screw seen near the point4 ,the figure below shows a tool holder which fits into the projecting parts of ,d1 and serves to hold the small flat tools4 ,below is a similar holder1 used for round-shanked drills4 ,f is one of three flat slabs upon which the tools are to be ground1 there being one of iron1 one of brass1 and one of hard wood with a flat strip of oilstone imbedded in it1 flush with its upper surface4 ,the tool and its fittings are generally arranged in a box with three drawers2 these contain the slabs of oilstone and metal1 with the powders necessary for grinding and polishing4 ,to use this instrument1 the point of ,d is adjusted to the required angle for one side of the point of the tool4 7,it is shown at #dj deg4 in the sketch47 ,the latter is then placed in the holder1 and made to project until1 when the angle of the chamfer is adjusted on the arc ,b1 the part ,a is level1 and therefore parallel to the surface of the grinding plate4 ,the whole thus forms a tripod1 the third leg of which is formed by the tool itself4 ,the latter is first rubbed on the oilstone with a little oil4 ,it is then finished more perfectly on the brass slab1 dressed with oilstone powder and oil4 ,previous to this the tool is moved one or two degrees more upright by the arc ,b4 ,a narrow facet is thus ground1 having a dull grey polish4 ,the tool is now carefully wiped clean1 and polished with crocus and oil upon the slab of iron4 ,if the point of the tool is central1 with a chamfer both ways1 the point of the tool holder is first adjusted on one limb of the arc and the tool ground1 and then the same adjustment made on the opposite limb1 so that the other side of the point can be operated upon4 ,thus tools of any angle and any bevel may be sharpened to a nicety without fear of altering the original form of the point1 and this may be done1 if necessary1 during the process of eccentric turning1 although1 as before stated1 it is better to fix the tools well sharpened at the commencement of the work1 and not remove them until at least one complete set of circles or other patterns have been cut4 ,illustration3 ,,fig4 #bee4 ,illustration3 ,,fig4 #bdf4 ,illustration3 ,,fig4 #bdg4 ,the instrument just described is evidently unsuited for the drills and bead tools which present a concave edge like #bdf ,a1 ,b1 ,c1 enlarged sketches of tools copied from ,holtzapffel's work4 ,for these the latter directs to use large or small cones 7#bdg7 of iron and brass1 to be dressed1 the first 7which is the polisher7 with crocus1 the second with fine emery and oil1 the flat side of the tool being held towards the point of the cone1 the bevel towards the thick end4 ,part of the edge of ,c must be delicately sharpened by hand1 as no guide can be used for the step-like portion of the edge4 ,the cones for sharpening are either mounted in the usual manner1 by one or both ends in the mandrel of the lathe1 or fitted into the spindle of a small drilling lathe-head1 the pulley of which is connected by a catgut band with that of the mandrel of the small lathe-head1 being fitted with a tailpiece to fit the rest socket1 or otherwise mounted on the lathe-bed4 ,the smaller cones especially require to be driven at a high speed4 ,when larger circles or mouldings are to be cut1 these small crank-form drills are no longer available1 and are replaced by a very simple1 but most effective contrivance called the eccentric cutter1 by which any work that is within the scope of the eccentric chuck and fixed tool may be executed with great precision and rapidity4 ,this is represented in ,fig4 #bdhbj--;a small oblong frame of brass1 about two or two-and-a-half inches in length1 and half an inch or so in breadth is traversed by a fine screw1 prevented from moving endwise by a collar1 as in the slide rest 7of which1 indeed1 this is a miniature74 ,a slide1 ,c1 with a little tool holder at the top of it1 is moved along the frame by the leading screw1 the head of the latter being graduated1 and also the upper surface of one or both sides of the frame4 ,the projection ,a1 fits into the end of the drill holder1 and is secured by a screw4 ,circles of a diameter equal to ,b1 ,b may thus be cut1 and their effect varied by placing tools of any form of edge in the tool holder4 ,such a tool as ,a1 will thus no longer cut a minute circle forming a hemispherical raised knob1 but will form a circular moulding1 such as that shown in part at ,fig4 #bdi1 except when the tool holder is on the middle of the frame and the tool concentric with the mandrel4 ,the single point tools1 however1 with single or double bevel1 are more commonly used1 in this cutter1 as mouldings can be turned as efficiently with hand beading tools1 with or without the eccentric chuck1 according to their required position4 ,it may here be mentioned that eccentric work should always be cut on wood of one colour1 or on ivory1 as the veinings of the richer fancy woods1 which are so beautiful in other cases1 only serve to confuse the tracery made by the eccentric cutter4 ,of all woods for fancy work with the eccentric chuck or cutter1 nothing equals ,african black wood4 ,it is1 however1 costly1 and only ranges to a diameter of five inches1 as great part is unsound4 ,the rind is hard1 thick1 and white1 similar to boxwood4 ,next to this for such work stands1 perhaps1 cocus1 or cocoa wood1 which is not the tree bearing the cocoa nut1 the latter being a palm1 which is more like cane in texture4 ,one of the most effective patterns to be formed by the eccentric cutter is the shell1 ,fig4 #bej1 in which one side1 or rather one portion of the circles composing it1 is very deeply cut1 while the opposite part is shallow4 ,this can be simply effected by throwing the sole of the rest out of the level1 by placing a thin piece of wood or metal across the lathe bed1 so as to tilt up the rest and place it 7with the cutter7 in an inclined position4 ,the tool will thus begin to cut at one part before it touches the surface elsewhere1 and the desired effect will be readily produced4 ,in using the eccentric cutter great rapidity of motion must be given to it1 but the tool must be advanced very carefully1 or it will be broken4 ,the lever handle is the best to use for the purpose4 ,akin to the shell pattern are those in which part only of the circles are cut1 leaving an effect shown by the border round ,fig4 #bej4 ,this is produced in the same way as the last1 being1 in fact1 a ring of shells in their initiatory stages4 ,this is a very effective snake-like pattern1 when fairly and cleanly cut4 ,when the eccentric cutter is used1 it must be remembered that the principle of work is not quite the same as with the eccentric chuck4 ,with the latter it was stated that the size of the circles depends on the slide rest and the position of their centres on the chuck4 ,in the present case the eccentric cutter regulates the sizes1 and the screw of the slide rest itself the positions of the centres of the circles1 since the part ,a of the cutter will always be in the centres of the same1 and this part is attached to the rest4 ,it will be understood that this remark respecting position of centres only relates to circles lying on the diameter of the work1 such as ,fig4 #bea1 the distance between a and b will be taken from the division plate on the pulley of the lathe4 ,the way to cut the above1 for example1 will be as follows3--,place the slide rest so that when the cutter tool is in the centre of the frame it shall be concentric with the mandrel4 ,in this position it will only make a dot in the centre of the work4 ,turn the screw of the cutter frame until you have a radius sufficient for the centre circle4 ,set the mandrel pulley with the index in ,no4 #cfj1 put in motion the overhead apparatus and cut the circle1 move the screw of the slide rest a few turns 7thus fixing the centre of the second circle71 until you find that the cutter will form the circle cutting the first1 and passing through its centre4 7,observe1 this being the size of the first1 the screw of the cutter frame is not turned47 ,cut the circle in question1 move the mandrel pulley a quarter round1 so that the index is in ,no4 #ij1 and cut another2 repeat the process twice more1 and #a1 #b1 #c1 #d1 will be cut4 ,the position of the centres of ,nos4 #e1 #f1 #g1 #h1 will now have to be determined as before1 by working the main screw of the slide rest2 but1 as their size is less than the preceding set1 the screw of the cutter frame must likewise be turned to diminish them to the required degree4 ,when by these combined movements their position and size have been determined1 they must be cut by the aid of the division plate1 in the same manner as the last1 and so on1 till the whole have been cut4 ,with respect to the ratio in which the circles diminish1 and the precise sizes of them1 no rule can be given1 as this must depend on the taste of the operator4 ,the sole object in this place is to show the principles whereby these patterns are to be executed4 ,a good deal of care is requisite in practice1 and the memory has to be often rather severely tasked4 ,the best plan is always to try a proposed pattern upon boxwood or paper1 before risking it upon more valuable material2 and1 where it can be done1 it is well to write down the numbers to be used on the various division plates4 ,a single false cut1 it must be remembered1 will spoil the whole work1 at a great waste of time1 loss of material1 and annoyance1 only to be appreciated by those to whom such an untoward accident may have happened4 ,the drilling apparatus1 without the eccentric cutter1 but fitted with a round-headed drill1 is used for the production of fluted works1 such as that shown in ,fig4 #beb1 ,a and ,b4 ,the drill being inserted in the end of the spindle1 and its point or end 7of any desired form1 either round1 flat1 or pointed7 being brought opposite one end of the flute1 the lathe is to be put in motion as in ordinary ornamental drilling1 the mandrel being1 of course1 held fast by the index and division plate4 ,at the same time that the drill in rapid motion is brought against the work by the lever handle1 the screw of the slide rest is slowly turned1 and thus the groove or flute is drilled out by the combination of longitudinal and vertical action4 ,the number of flutes in any given size of cylinder is determined1 first by a horizontal sectional plan on paper1 and regulated accordingly by help of the division plate and index4 ,in making such an article as ,fig4 #beb1 it will economise material1 whether ivory or blackwood1 or a combination of the two1 to form it of at least three pieces1 making the divisions at ,c1 ,d4 ,care should be taken to leave below the bowl1 which should be as thin as paper if of ivory1 the part ,c on which the beads are to be drilled4 ,the pedestal can then be screwed into this1 and will not penetrate the bottom of the bowl4 ,ivory may be screwed in an ordinary set of stocks and dies if care is taken not to screw up the latter too quickly4 ,lard may be used as a lubricant in cutting this material1 whether for sawing or drilling4 ,the part with raised mouldings between ,a and ,d is ornamented with a vertical or universal cutter1 and for greater ease and exactness a template may be used in the slide rest by means of which all the curves of the moulding may be accurately followed by drill or cutter4 ,the minute beads round the edges of the small mouldings are made with two sizes of ,a1 ,fig4 #bdf2 a little knob is thus formed rising from a hollow4 ,the small knobs used as feet may be rapidly formed by a hand beading tool of semicircular section1 similar also to ,a1 ,fig4 #bdf4 ,a pin may be left on each1 or they may be drilled and attached by small screws of brass wire made on purpose4 ,the following cement will enable the turner to make an ivory bowl for the above ornament so thin as to be transparent2 indeed it may be thus made so thin as to bend under the fingers1 although such extreme tenuity is not required in the present case4 #bj ,a newer pattern appears on a later page4 ,illustration3 ,,fig4 #bdh4 ,illustration3 ,,fig4 #bdi4 ,illustration3 ,,fig4 #bej4 ,illustration3 ,,fig4 #bea4 ,illustration3 ,,fig4 #beb4 ,take the finest sifted lampblack and make it into a paste with glue1 about as thick in consistency as paint4 ,after turning the ivory tolerably thin1 paint this on the inside2 let it dry1 and repeat the process till sufficient is laid on to form a kind of hollow core1 of strength sufficient to support the ivory against the action of the tool4 ,the material may now be thinned and ornamented from the outside4 ,when finished1 soak a few minutes in warm water1 and then agitate in cold2 it will become quite clean as before4 ,by altering the direction of the motion of the revolving cutter1 the several cuts made by it will assume a different character1 and the work will present a series of hollows scooped out1 so to speak4 ,the cutter1 #bec1 being fixed in the tool holder of the top slide1 will work vertically only1 and produce patterns similar to ,fig4 #bed1 of the nature of basket work4 ,this is exceedingly effective1 and1 as it may be cut so deeply as to penetrate the material of hollowed works1 the latter may be lined with red or other bright coloured silk or velvet1 and a variety of designs thus worked out4 ,it is very necessary in using the vertical cutters to move the tool holder forward very gently1 giving it at the same time great rapidity of revolution4 ,without this it will at once stick fast in the work4 ,the character of the designs may1 of course1 be infinitely varied by using cutters of different sections1 as in the case of work done with fixed tools with the aid of the eccentric chuck4 ,the same cutters will1 in fact1 serve both purposes4 ,fig4 #bee represents a tool similar to the last1 but arranged to cut horizontally4 ,with this1 fluted work can be done3 but it is evident that the cord from the overhead apparatus cannot here be directly applied1 owing to the horizontal position of the driving pulley4 ,additional guide pulleys1 therefore1 become necessary1 and1 when these have to be arranged1 the apparatus is generally modified1 and the universal cutter is used1 of which one form is shown in ,fig4 #bef1 and though it is not so good a pattern as that which is described in a later page1 it is nevertheless suited for use with the old pattern of slide rest already delineated4 ,with this the direction of the cuts may be varied at pleasure--they may be perpendicular1 horizontal1 or radial1 and1 when the templates before mentioned are added to the slide rest1 an infinite variety of devices may be cut upon spherical and curved surfaces1 so that the cutter thus modified is fully entitled to its title of universal4 ,the design1 ,fig4 #beh1 is entirely the work of revolving cutters and drills used with a template of the required section4 ,it is intended for a lady's workbox1 opening with a hinge on the line1 a1 b1 and containing in separate compartments the various articles required4 ,it may be made entirely of ivory1 lined with red or blue satin1 and the flutes round the body may be cut through to allow the lining to appear4 ,in the latter case1 however1 if the box is of ivory1 black velvet may be used to enhance the contrast1 and1 as the glossy pile would be outwards1 a second lining of any desired colour should be added with the best side inwards4 ,the rings for the handles1 as for all similar purposes1 can be quickly made with the tool1 ,fig4 #bei4 ,a hollow piece of ivory being taken1 and turned smooth inside and out1 one side of the tool is applied1 as in the figure1 so as to cut half through the work4 ,it is then removed1 and the opposite edge applied to the inside until the ring falls off completely finished4 ,it is then cut through with a thin saw or knife1 and inserted in the tailed ring or other projection intended to receive it4 ,handsome works in ivory should always be kept under glass shades4 ,the universal cutter shown in ,fig4 #bef consists of a plate with chamfered edges to fit the tool receptacle of the slide rest1 having near each end small poppets which support the round rod connecting the pulley bearing piece1 ,a1 with the part1 ,e1 which carries the tool1 ,f1 the latter being attached by a small slot and set screw to a cylinder revolving in ,e1 and having at its upper end the driving wheel1 ,c4 ,at ,g is a circular piece or wheel racked on the edge1 and turned by the tangent screw1 ,g4 ,the hinder poppet is rectangular1 and has divisions marked upon it on each side of the angle numbered from the apex4 ,the racked wheel may with advantage be similarly graduated4 ,when the part ,e is vertical the cutter will be in a position to work horizontally1 and the pulley support will be vertical4 ,by turning the tangent screw1 both the parts move together2 but if desired the pulleys can move independently by unscrewing ,d and ,l4 ,the angular poppet may be made semicircular if preferred1 the degrees being numbered either way from #j in the centre4 ,when the tool holder is horizontal1 or approaching that position1 the nut1 ,d1 must be loosened1 and the pulleys placed so that the cord will not slip off4 ,they may be dispensed with if the apparatus is to be used ,,only for vertical cuts 7the holder1 ,e1 will be horizontal72 but if a radial pattern is to be cut1 in which the angle is to be constantly varied1 the pulley piece must be used and the pulleys re-arranged at ,d1 as required from time to time4 ,there is a somewhat neat and serviceable little apparatus represented in ,fig4 #bei;,a1 to take the place of the slide rest and its revolving cutters1 and although its powers are limited1 much may be done with it4 ,the spindle ,a1 works through brasses in the poppets1 ,b1 ,b1 and is put in motion by a cord from the overhead passing over the pulley in the centre4 ,this spindle1 which holds the crank-formed and other drills in a socket at one end1 moves freely through the bearings endwise1 and is kept back from the work by a spiral spring working against the end of the handle1 ,c4 ,this handle does not turn with the spindle1 but is mounted like the handle of a carpenter's brace1 or that of an ,archimedean drill stock4 ,the whole apparatus fits into the socket of the ordinary rest4 ,a screw should have been shown in the drawing1 passing through ,b towards the pulley1 to regulate depth of cut4 ,illustration3 ,,fig4 #bec4 ,illustration3 ,,fig4 #bed4 ,illustration3 ,,fig4 #bee4 ,illustration3 ,,fig4 #bef4 ,illustration3 ,,fig4 #beh4 ,illustration3 ,,fig4 #bei4 ,illustration3 ,,fig4 #bei;,a4 ,illustration3 ,,fig4 #bfj4 ,once fixed by the screw of the latter in its intended position the tool is advanced to the work in a straight line by pressing the handle ,c1 and is released from the cut as soon as this pressure is withdrawn4 ,with different sizes of cranked1 forked1 or round ended drills1 a good deal of ornamentation may be done with this simple tool1 which is also useful for ordinary light drilling4 ,by putting in the socket a round ended drill1 and using the radial movement 7turning the whole round in its socket in the arc of a circle71 short flutes can be drilled out deep in the middle1 forming basket work similar to ,fig4 #bfj1 which is exceedingly pretty when carefully executed4 ,there is little difficulty in making drills and cutters1 as steel of all sizes in round and square bars may be had at the chief tool shops1 especially at ,fenn's1 in ,newgate-street4 ,in making the revolving cutters1 however1 it is necessary to observe the position of the axial line1 which must pass through the cutting edge4 ,after the drill is roughly finished1 therefore1 it should be mounted in the tool holder with which it is to be used1 and carefully tested upon a piece of unimportant work4 ,if in revolving against the latter it leaves a part of the material untouched1 the edge is not truly in the centre of rotation4 ,the flat side of the drills are to be diametrical1 and hence1 as ,holtzapffel remarks1 these drills can only be sharpened on the end4 ,the latter authority also says most of the drills embrace 7in contour of edge7 only about one-fourth of the circle1 as when the drills are sharpened with one bevel they can only cut on the one side of the centre1 and if the drills were made to embrace the half circle the chamfer of the edge on the second side would be in the wrong direction for cutting1 and consequently it could only rub against the work and impede the action of the drill4 ,all ornamental cutters and drills should be kept in a box with small separate divisions to fit the shanks1 which are all of one size4 ,the points can then be seen and the selection made of any required pattern4 ,,curiosities4 ,many turners take special interest in the production of objects in the lathe1 that at first sight appear impossible to be produced solely by its means4 ,inasmuch as such works manifest the skill and patience of the artificer1 they will always meet with appreciation2 and1 although otherwise useless1 they serve as elegant objects of vertu1 and are well worthy a place among the rare ornaments of the drawing rooms4 ,when first the ,chinese balls1 consisting of a set of hollow spheres one within the other1 all exquisitely carved1 were brought to ,england1 it was believed they were made in hemispherical pieces1 united round the equatorial line with some kind of cement1 the joint being carefully concealed4 ,i am not sure that they are made in a lathe in ,china2 but1 at all events1 they are so made in ,england1 and our home productions almost rival those of that strange yet clever nation4 ,i say almost1 because the carving in ivory done by the ,chinese is in some respects unequalled1 nor do ,i suppose that work requiring in many instances years of patient industry could be made to repay the cost of manufacture in ,england4 ,no sooner were these curiosities in vogue here than all kinds of similar impossibilities were manufactured4 ,stars with from three to a dozen rays made their appearance1 enclosed sometimes in similar sets of hollow spheres--the rays projecting beyond the limits of the outer shell--others were wondrously enclosed in cases with flat sides1 cubes1 pyramids1 six1 eight1 twelve-sided hollow cases1 all turned fairly in the lathe1 were produced with similar contents1 so that the apple in ,king ,george's dumpling became a very secondary wonder4 ,the starry inmates were evidently too large for the houses2 yet there they were--legs and arms1 of course1 sticking out through doors and windows1 simply because there was no room for them inside4 ,we will penetrate the mystery1 commencing with a single hollow ball containing a star of six rays1 the bases of the latter standing on a central cube4 ,in the first place a perfect sphere is required1 and consequently the slide rest and template1 or spherical rest1 must come into requisition unless the turner can produce a ball by hand tools alone4 ,let this sphere1 or rather its boundary line1 be drawn on paper of full size with the compasses1 ,fig4 #bfb1 ,a1 ,b1 ,c1 ,d4 ,draw the diameters ,a1 ,d1 ,c1 ,b1 at right angles to each other4 ,this will give you five points1 which on the sphere itself 7on which these lines will have to be drawn1 including also another1 answering to ,a1 ,b1 ,c1 ,d7 are centres of six openings1 here represented by the circles1 through which the tools have to be introduced to hollow out the sphere and form the star4 ,the points of the latter will be in the centres of these openings4 ,draw in addition the plan of the central cube1 and one ray of the proposed star2 next draw an inner circle1 here dotted to mark the thickness of the outer envelope4 ,the object of this drawing is to enable you to make a set of curved tools1 one of which is shown black at ,e1 and a set are marked on a plate of steel1 from which they must be cut out4 ,a close inspection of the figure will show that if ball1 ,fig4 #bfb1 were turning on the point ,a1 ,a ,d being its axis of revolution1 tools of the given section introduced at ,d would cut away the material round the point or ray1 leaving the latter standing2#ba and this operation repeated at the five remaining openings would entirely free the central cube with its rays according to the proposed design4 ,the tools have to be introduced in order1 beginning with the smallest2 and although the above remarks will make clear the principle1 there are several points to be attended to in practice1 and some few accessories are required which will now be explained4 ,it is evident that for every different sized sphere fresh sets of tools will be requisite1 which will also vary in pattern according to the intended form of the central base on which the rays stand2 a cube or flat-sided solid requiring one tool at least1 with a rectilineal edge2 spherical or other solids demanding others whose ends are of different section4 ,hence1 in all cases1 full-sized plans of the proposed work must be drawn1 and special tools designed therefrom4 #ba ,there is an error in the position of this tool1 which1 thus placed1 would not leave the point of the star4 ,fig4 #bgj will explain the method better4 ,illustration3 ,,fig4 #bfb4 ,illustration3 ,,fig4 #bfi;,a4 ,illustration3 ,,fig4 #bfi;,b4 ,fig4 #bfi;,a is introduced to show more clearly the result of the application of the first set of tools1 or rather of the first application of the set1 as the latter are used throughout4 ,the blackened part will be entirely cut away in this operation1 the shaded part meeting it will be removed when the tools are transferred to the adjacent opening1 the cuts meeting those first made4 ,hence the tools need only reach from a to b1 and can be more easily introduced than if the curved part were longer4 ,gauges1 ,fig4 #bfi;,b1 ,a1 must likewise be made of thin brass or tin1 that the progress of the work may be examined1 and each opening in the sphere should likewise be measured with a gauge1 or with compasses fixed to one width by an adjusting screw4 ,the proper chuck for this work is the capped ball chuck already described1 by loosening the cap of which any one of the six openings may be brought under the action of the tool1 these openings being1 in fact1 bored out simultaneously with the formation of the star4 ,after the first point or ray of the star has been completed1 the ball may be reversed and the opposite ray formed4 ,these are now to be secured by plugs1 which are to be turned conical1 to fit the opening of the ball at one end1 and of a length to rest upon the central cube at the other1 being also bored out to fit over the rays1 which they should embrace closely at top and bottom1 even if not at the other points of its length4 7,fig4 #bfi;,c1 ,a and ,b47 ,this is to be repeated as each ray is formed1 so that the central star may be held in place until the work is finished1 when the plugs are removed1 and the star will be entirely detached4 ,the above-named tools being straight on the right hand side of the shank will not form a finished conical point or ray4 ,hence it is recommended to file away that side1 so that when flat upon the rest1 the back of the tool may be an exact counterpart of a ray1 ,fig4 #bgj1 ,a4 ,there is1 however1 no absolute necessity for this1 as the star point can be first made blunt1 with perpendicular sides1 which can then be neatly finished by a separate tool made for the purpose1 and kept up to a very keen edge4 ,the first and smallest of the set of tools here shown1 is the one with which the flat sides of the cube are formed1 and it must be bevelled from underneath1 so as to present a cutting edge on the end4 ,the curved tools should cut on the end and both sides of the crook4 ,illustration3 ,,fig4 #bfi;,,cc4 ,illustration3 ,,fig4 #bgj4 ,illustration3 ,,fig4 #bgj;,a4 ,illustration3 ,,fig4 #bga4 ,it is quite possible to make the above in mahogany1 but a closer grained wood is much to be preferred1 as the tools used--which are held flat upon the rest--are rather scraping than cutting1 and mahogany1 and fibrous woods in general1 cannot be thus worked neatly4 ,boxwood is1 in every respect1 the best material to begin upon1 ivory and blackwood being reserved until the eye and hand have become accustomed to such work4 ,the whole operation requires great care1 and is rather tedious1 but the result ought to be a sufficient reward4 ,the external surface may1 of course1 be ornamented with the usual apparatus1 but the star should be left clear and sharp4 ,the edges of the openings should have a light beading1 cut with a bead tool1 ,fig4 #bga1 ,a and ,b4 ,,grooving ,,and ,,mortising ,,small ,,work4 ,amongst the various purposes to which it is possible to apply the lathe1 may be noticed the drilling out grooves and mortises1 a method used in some of our ,government arsenals1 for cutting the recesses for the reception of the ,venetian lath work in cabin doors4 ,the same method is1 of course1 applicable to numberless similar cases1 although designed for the special object named4 ,the apparatus is shown complete in the drawing1 ,fig4 #bgb1 and the component parts in the succeeding diagrams4 ,a is a kind of compound slide rest1 or vertical straight line chuck1 having a movement in a direction parallel with the lathe bed at ,f2 while the circular plate being pinned through its centre to a slide1 ,h1 can be moved up and down by means of the handle ,g4 ,this circular plate can be set in any position1 and has a projecting shelf or rest to carry the work1 which is steadied by guide pins1 as will presently be explained4 ,the part ,f1 has a bed similar to that of an ordinary slide rest1 which is clamped to the lathe bed by a bolt and nut1 as usual4 ,this carries likewise chamfered bars1 between which slides the horizontal plate to which the vertical part of the apparatus is attached4 ,this is first a plate with chamfered edges1 ,fig4 #bgc ,a1 and a second similar but rather wider plate1 ,fig4 #bgd ,b1 with guide bars1 likewise chamfered1 to slide upon ,a4 ,from the front of ,b rises a stout pin1 on which the circular plate1 ,c1 turns1 which can be clamped by a central nut1 or otherwise1 as in an ordinary compound slide rest4 ,this nut should not project above the general level of the plate4 ,on the face of the latter is1 as previously stated1 a rest1 or narrow metal shelf1 ,d1 and pins1 e1 f4 ,the plate may be variously arranged in this respect by substituting any kind of holdfast or guide1 according to the work desired to be done by its aid4 ,the upper slide is depressed by a hand lever acting on a pin fixed in the sliding plate1 ,fig4 #bge2 or1 if preferred1 by a similar lever1 with a quadrant and chain1 or rack movement4 ,the horizontal slide is worked by means of a stirrup for the foot1 with cord attached1 acting on a bell-cranked lever1 seen in the first figure4 ,to cut the grooves in a bar1 for ,venetian blinds--as described--the lath to be drilled is attached to a flat strip of thin iron1 drilled with holes1 ,fig4 #bgf ,a1 as wide apart as the required distance between the grooves4 ,it is then laid against the shelf1 and the guide pins are made to enter the holes in the iron4 ,the clamping nut of the round plate is loosened1 until the bar is set to such an angle that the grooves to be cut will form vertical lines1 ,fig4 #bgf4 ,it is then clamped securely4 ,illustration3 ,,fig4 #bgb4 ,illustration3 ,,fig4 #bgd4 ,illustration3 ,,fig4 #bge4 ,illustration3 ,,fig4 #bgc4 ,illustration3 ,,fig4 #bgf4 ,it is necessary to be able to adjust the piece to be cut1 as regards its height1 above the lathe bed4 ,this is effected in part by the position of the movable shelf--fixed by pins--and partly by guide or set screws1 which regulate the traverse of the slides4 ,suppose the bar adjusted as in ,fig4 #bgf1 the groove to be cut being brought opposite to the drill4 ,the set screws--two of which are seen at x1 x1 ,fig4 #bge--;acting on the handle1 regulate the precise length of each groove4 ,a similar stop1 connected with the horizontal part of the machine1 regulates the advance of the wood towards the drill1 and thus the depth of the cut4 ,hence it is only necessary to set these carefully at starting--the pins on the guide plate insuring the proper width between the grooves--and the lathe being put in motion1 any number of precisely similar grooves can be drilled with the utmost rapidity and neatness4 ,an inspection of the drawings will show what numberless purposes may be served by this simple apparatus1 which may be modified in its details1 while its principle of action is maintained4 ,the drill should have a chisel and be kept to a keen edge4 ,the lathe should be put in rapid motion1 and if the required cut is to be deep1 it should be cut at twice4 ,the lower slide should return to its place by means of a spring when the foot is raised1 the vertical slide being movable in both directions by means of the slotted part of the handle4 ,,note4--,the above being taken from an apparatus for a steam lathe1 the stirrup action maybe used1 as the foot is at liberty4 ,a foot lathe would require a slight modification4 ,in ,fig4 #bge1 the depressing handle is shown as if the chamfered bars were fixed to the sole plate1 and the plate ,a1 were movable1 as is sometimes the case4 ,when made according to the above description1 the handle would1 of course1 be pinned to the fixed vertical plate1 ,a1 to which also the stops would be attached1 and the pin which passes through the slot of the handle1 must project from one of the chamfered bars4 ,either plan may be followed1 but the pattern described is calculated for a stronger apparatus2 inasmuch as the vertical plate can be secured more firmly to the chamfered horizontal slide than the mere pair of guide bars--the two might1 in fact1 be made in one casting1 if preferred4 ,,ornamental ,,turning4 ,the slide rest previously described1 although applicable to the purposes of ornamental turning1 has one disadvantage4 ,it is necessary that the various pieces of apparatus to be used with it should have a foundation plate with chamfered edges to fit accurately between the guide bars4 ,this is often inconvenient1 and adds to the difficulty of making1 and consequently to the cost of such pieces4 ,in addition to this drawback1 it may happen that one of these fittings by being more frequently used becomes more worn than another1 so that the guide bars require constant re-adjustment1 and their accuracy and parallelism become impaired4 ,to obviate these and similar inconveniences the slide rest is now commonly made like ,fig4 #bgg1 and a tool receptacle1 ,fig4 #bgh1 is fitted to slide between ,m1 ,m1 and is so arranged as to hold securely the universal cutters and other apparatus required for ornamentation or for plain turning4 ,these are all made with a rectangular bar fitting the longitudinal channel in the middle of the receptacle1 and are secured by the following simple contrivance4 ,it will be seen by the drawing that the central channel is widened at ,a1 ,a1 and that a groove or saw-cut ,b runs along the inside from end to end4 ,this groove is continued in a similar manner on the side next to the reader4 ,fig4 #bhj represents an ordinary tool holder1 with a rectangular shank ,a1 and clamping screw ,b1 by which the tool c is secured4 ,the part ,a is laid in the central channel1 and a small piece of metal shaped like ,fig4 #bgi is inserted in one of the open spaces1 ,a1 ,a of the receptacle and slid along with its lower flange in the saw-cut until clear of the enlarged part of the channel4 ,it is thus retained1 and the clamping screw which passes through its centre is brought to bear upon the piece to be fixed1 which is thereby securely held in its required position4 ,two of these holdfasts are generally used at the same time4 ,if the main bar of the tool holder is not quite thick enough to be clamped1 then it is only necessary to lay a small plate below it4 ,by the above simple means1 the necessity for fitting each individual piece of apparatus to work upon the chamfered guides is done away4 ,in order to ensure the position of the sole of the rest at right angles to the lathe bed a kind of saddle1 ,a1 ,fig4 #bha1 is used4 ,this is of cast iron or brass1 accurately planed on the upper surface1 and has a projection fitting between the bearers of the lathe4 ,the usual holding down-bolt passes through the hole in the centre1 securing the saddle and the rest at the same time4 ,the usual arrangement of a kind of double socket1 the inner one rising at pleasure by being tapped into the outer1 has already been described1 and serves for accurate adjustment of the height of the rest4 ,it is convenient1 in addition1 to have a stop or set screw under the bed of the rest1 and a similar one on the top of the socket1 so placed that when the frame is swung round it shall stop precisely at right angles to its former position4 ,thus1 if the tool is first required to be used upon the side1 and then upon the face of the object to be turned1 these two positions are obtained at once1 and can1 if necessary1 be alternated without any re-adjustment of the moving parts of the rest by the aid of the set square4 ,the receptacle-holder is generally advanced by the hand lever1 ,fig4 #bgi1 one pin of which fits into the hole in the guide-bar as seen in the drawing1 while the other falls into a short slot e1 made in the upper surface of the receptacle1 or of the piece of apparatus to be used in it4 ,of course1 this arrangement may be reversed1 one or both pins being fixed to the rest and its receptacle slide1 and the holes made in the lever4 ,sometimes1 however1 a slower and more regular movement is required than it is possible to give in this way1 and the lever is replaced by the leading screw ,c1 ,d1 ,fig4 #bgh1 the head of which is removable1 and can be replaced by a small winch handle4 ,this screw is tapped into the lug cast upon the receptacle1 and its point is of the form shown4 ,the latter fits into a hole in the pillar ,a1 #bgh1 and is retained by a pin1 which falls into the groove1 ,d1 ,fig4 #bgh1 and prevents the screw from advancing or receding without carrying the sliding plate with it4 ,the pin being removed1 the screw will no longer act in this way1 and the slide may be moved by the lever instead4 ,the other screw1 ,e1 ,f1 of fine pitch1 serves to regulate the advance of the receptacle1 and consequently the depth of cut of the tool--a round head with divisions on its edge is attached to one end1 which abuts against the pillar ,b1 ,fig4 #bgg1 which latter has a mark on its top to act as an index4 ,thus the advance of the tool can be regulated to a great nicety1 and successive predetermined and different depths may be reached and repeated at pleasure1 as is sometimes necessary4 ,c1 ,c1 ,fig4 #bgg1 is one of a pair of stops which can be fixed by their screws at any two points of the bed of the slide rest4 ,these serve to regulate the distance which the top slide and tool holder are intended to traverse1 as in drilling a number of flutes of equal length1 and many similar works4 ,they are usually made of gun-metal1 the screws of iron or steel1 or of a metal called homogeneous1 which may be described as between the two1 and1 being pleasant to work1 is worthy of notice4 ,it is absolutely necessary that the slide rest for ornamentation should be made with the greatest nicety4 ,the slides must work equally smoothly from end to end of their traverse4 ,the pitch of the screws must be not only fine1 but even and regular1 and the screw itself of precisely the same diameter from end to end1 else it will work loosely through its nut in one place1 and jamb in another4 ,it is extremely pleasant to feel the exquisite smoothness and oiliness1 for no other word will express it1 of the movements of sliding parts in the workmanship of ,munro or ,holtzapffel1 especially if compared with inferior work4 ,good amateur's work indeed is often far superior to that which is sometimes advertised1 and perhaps a few hints may not be out of place here1 relative to the construction of this necessary addition to the lathe4 ,illustration3 ,,fig4 #bgg4 ,illustration3 ,,fig4 #bgi4 ,illustration3 ,,fig4 #bhj4 ,illustration3 ,,fig4 #bgh4 ,illustration3 ,,fig4 #bha4 ,illustration3 ,,fig4 #bhb4 ,first of all1 the frame of the rest must be accurately at right angles to the spindle1 which fits into the socket4 ,these should1 therefore1 be turned together1 supposing the amateur not to have a planing machine4 ,the whole may be mounted as ,fig4 #bhb1 where ,a represents the carrier plate or chuck2 ,b1 the driver1 the tail of which should be as long or nearly so as the frame from c to ,d2 ,f is the side tool to be fixed in the slide rest for metal4 ,the effect of this arrangement is to plane the face of the slide with transverse strokes instead of lengthwise4 ,it may be afterwards finished and polished with oilstone powder on a flat slab of planed iron4 ,when the face is finished1 the whole must be reversed1 the pin of the carrier plate will bear against the frame1 which thus acts as a driver1 and the spindle must be turned4 ,in this way accuracy is ensured if the slide rest used is carefully set4 ,the chamfered sides of the slides are difficult to work with the file1 but may be so done with care1 and with a template of the desired bevel as a guide4 ,the great secret is to take plenty of time1 not to press too much upon the file nor to move it too quickly over the surface2 fine even strokes1 especially towards the finish1 must be given1 and a final polish with oilstone powder and oil used on a piece of a stick4 ,in turning the screw a back stay must be fixed opposite to the tool in the slide rest to insure the contact of the cutting edge without bending the work4 ,presuming that the screw will be cut with stock and dies1 it may be stated as a caution that the latter must not be tightened except at the commencement of cutting the thread deeper4 ,the return of the tool by a backward motion 7or unscrewing71 should not be used as a cutting action1 and therefore1 should be carried on with the dies in the same position which they had during their descent4 ,at the beginning1 therefore1 of each downward movement the dies must be tightened and oiled1 and they must not again be touched till the bottom of the screw has been reached1 and the upward movement also has been completed1 so that they have arrived again at the starting point4 ,if tightened at any other time the screw will be either conical or of a wavy section1 either of which forms would be fatal to its use4 ,the castings for such a rest should be of malleable iron1 if possible1 as being much more easy to work2 the guide bars may be of gun metal1 as also the chamfered bars1 which work on the main frame4 ,this will give a more finished appearance1 and will on the whole be more durable and satisfactory4 ,,the ,,eccentric ,,cutter ,,frame4 ,one of the most useful tools for ornamentation1 especially of plain surfaces1 such as the top of a box cover1 is the eccentric cutter1 ,fig4 #bhc4 ,the shank1 ,a1 lies in the receptacle holder of the slide rest1 and is drilled throughout to receive a steel spindle1 carrying at one end a double pulley1 ,b1 to receive the cord from the overhead motion1 and at the other frame1 ,e1 with its leading screw1 of which the movable milled and graduated head is seen at ,h4 ,this frame has one surface1 level with the centre of the main spindle1 which is cut away as shown1 and1 consequently1 as the point of the tool is on its flat side1 which latter rests upon the frame 7the bevel being below71 this point can1 by the tangent screw1 be brought into a line with the centre of the main spindle1 so that when the cord from the overhead is passed round ,b1 the spindle revolves with great rapidity1 and the point of the tool1 ,k1 in the position described1 makes a simple dot4 ,by turning round the milled screw head1 ,h1 either by the thumb and finger or by a small winch handle1 fitted on the square part beyond the head of the screw1 the tool holder1 ,d 7which is in one piece with the nut of the leading screw71 is made to traverse the frame1 and the tool will cut a circle small or large according to the eccentricity thus given to it4 ,in ,fig4 #bhe ,d1 is the tool holder on the front of the frame2 ,c1 the end of the spindle2 ,l1 a bell-shaped washer1 which is acted on by the small square-headed screw1 drawing ,d towards the frame and clamping the tool4 ,the whole is in the figure of full size4 ,the tool holder is in one piece with the nut1 through which passes the leading screw1 and which is continued as a screw for the action of the bell-shaped washer and tightening nut2 hence it is necessary to allow a degree of play between the nut and leading screw1 to prevent bending the latter when clamping the tool4 ,this is effected by filing off the threads in the nut at the top and bottom1 to render the whole slightly oval4 ,the remaining threads suffice for the action of the leading screw3 a very slight degree of play in the required direction will be found sufficient4 ,the powers of the eccentric cutter frame will be found sufficiently extensive to make it a most serviceable1 perhaps necessary1 piece of lathe apparatus4 ,if it cannot be said absolutely to supply the place of the eccentric chuck1 it has nevertheless the advantage of great lightness of construction1 lowness of cost1 and ease of manipulation4 ,the weight of the eccentric chuck1 whether single or double1 as of all chucks in which sliding plates are used1 is a sad drawback to their value--a drawback unfortunately beyond remedy1 and specially felt when the slides are drawn out to a great degree of eccentricity4 ,combined together1 these two form a compound eccentric chuck1 and in this way are capable of nearly everything in the way of eccentric ornamentation4 ,where the chuck is not to be had1 it is by all means advisable to procure the cutting frame1 for which the writer confesses a great partiality4 ,it appears1 indeed1 to him a far more rational proceeding1 as it is also now of extensive application1 to act upon fixed work by revolving or moving tools1 instead of proceeding in the contrary way2 and all these little tools used with the overhead apparatus are so lightly and elegantly constructed1 and so well adapted for the parts they have to perform1 that the originator of them 7native talent devised them71 deserves to be well and lastingly remembered2 instead of which it is doubtful whether his name is even known4 7,sic transit is a quotation too stale for this work47 ,illustration3 ,,fig4 #bhc4 ,illustration3 ,,fig4 #bhe4 ,illustration3 ,,fig4 #bhe;,b ,to cut circles deeper in one part than another--the shell pattern1 for instance--with this tool1 it is not necessary to alter the level of the sole of the rest1 as it is when the eccentric chuck is used with a fixed tool1 as it suffices to set the rest itself at an angle1 by moving it round in the socket1 so that the revolving tool should touch the face of the work sooner at one point than at an opposite one4 ,in the same way the work may be considerably undercut on one side of the circles1 by giving the angular set to the rest1 and placing a tool in the holder1 with a point of the form shown at #bhe ,b4 ,there is nothing prettier than this undercut work when well and sharply done1 for which purpose the tool should not only be rendered keen on the hone1 but burnished and polished on the brass and iron slabs already described4 ,the following remarks on the work of this cutter frame on flat surfaces only1 will be useful to the reader in designing and working out the various combinations of circles1 intersecting or otherwise1 which it is calculated to produce4 ,on a surface represented by #bhf ,a1 the line of circles1 a1 a1 is on a diameter1 and1 supposing them to be described by the eccentric cutter 7or by a simple double-pointed drill71 their centres are obtained by means of the leading screw of the slide rest1 moved the requisite number of turns between each cut1 while the work is retained in a fixed position on the mandrel4 ,but if the line of circles is on such a line as b b1 above or below the centre1 and consequently not on a diameter1 it is plain that no movement of the slide rest or cutter1 or both1 can avail to place them in position1 except with great difficulty and tedious working with the division plate of the lathe and the screw of the slide rest4 ,hence the eccentric chuck must be brought into play1 and being fixed with its slide in a vertical position1 the screw is turned and the work is lowered thereby until the line b1 b1 is on a level with the point of the tool4 ,the eccentric cutter or double drill will then suffice to work the row of circles4 ,when the centres of the circles are themselves on parts of the circumferences of other circles1 the division plate of the lathe or of the eccentric chuck will be called into requisition1 according as these circles are concentric with the mandrel or otherwise4 ,in ,fig4 #bhf;,b1 the curved lines are parts of circles of equal size with that representing the surface of the work1 and their centres lie on one and the same diameter1 viz41 at opposite extremities of the line1 a1 b4 ,being thus eccentric to the work1 the division plate of the chuck is used to arrange the intersecting circles of the pattern--its slide having been first drawn down1 until the centre of the arc to be worked with circles is brought opposite to the tool4 ,the work will be in position when1 on turning the mandrel slowly1 the cutting point of the tool passes across its centre4 ,the division of the original circle is in this instance into four parts1 two of which are thirds1 and two sixths of its circumference4 ,the arcs of circles are also lines equal to thirds of the circumference of the work4 ,it is well to remember this division of a circle by other equal circles described round it from points on its circumference1 these circles passing through the centre4 ,the original circle will in this way be divided1 as shown at ,c1 into six equal parts4 ,to produce it with the aid of the eccentric cutter is easy4 ,set the tool of the cutter first to the centre of the work1 so that on revolving it will make a simple dot4 ,this should always be done1 whatever pattern is subsequently to be cut4 ,fix the index of the division plate of the lathe at #cfj4 ,move the screw of the slide rest until the point of the cutter1 on being advanced1 rests on the circumference of the circle previously cut upon the work1 or on the circumference of the work itself1 if the divisions are to reach the edge4 ,screw back the tool 7not the rest7 until its point reaches the centre of the work and cause it to revolve so as to cut one arc4 ,move the lathe pulley forward to #fj and cut a second arc1 and so on1 advancing #fj each time1 and the figure will be cut4 ,this division of the circle will form the groundwork of many handsome patterns4 ,when the arcs thus formed are intended merely to be the lines of centres1 and not themselves to form integral parts of the pattern1 they should1 nevertheless1 be marked with a pencil in the tool holder1 if possible1 as there will be less liability to error in working the proposed pattern4 ,in the present advanced stage of the art of turning1 mere surface work done by the eccentric cutter is rather apt to be despised1 owing to the extended powers of ,ibbetson's or ,plant's geometric chuck2 but1 valuable as the two latter are1 they are necessarily so costly that few can obtain them1 whereas the little cutter frame is comparatively cheap1 and it is really capable of very exquisite work in skilful hands4 ,illustration3 ,,fig4 #bhf;,a ,illustration3 ,,fig4 #bhf;,b ,illustration3 ,,fig4 #bhf;,c ,,segment ,,engine4 ,fig4 #bhg4 ,in very many cases of ornamentation it is required that the mandrel1 instead of making an entire revolution1 should stop at a given point in both directions1 so that1 for instance1 the turner should be able to move it #fj1 #hj1 or #ajj divisions to and fro1 with the certainty of its not advancing beyond that distance4 ,this is effected by the racked and divided brass wheel ,b1 fixed on the mandrel against the small end of the pulley4 ,this wheel is sufficiently thick to allow of racking part of its edge to be acted on when necessary by the tangent screw1 and leaving the other part for divisions1 which are generally seventy-two in number1 and marked in figures at every sixth division4 ,on the other side of the plate are a number of holes drilled through its whole thickness to receive stop pins1 ,fig4 #bhi1 ,p1 which are sawn through as shown1 that they may spring1 and fit the holes tightly4 ,there are seventy-two holes corresponding with the divisions4 ,these pins are about #c_/afths of an inch diameter1 generally with flattened heads1 and a hole through them to receive a pin to aid in removing them4 ,the holes are sometimes made in the edge1 instead of the side of the segment plate1 but the latter is the best position4 ,at ,fig4 #bhh1 ,t1 is seen the interior part of the poppet1 with a piece of brass let in1 and fixed securely1 in which are inserted two screws1 against which the segment stops abut1 and prevents further rotation of the pulley4 ,side by side with this latter piece is placed the frame which carries the tangent screw4 ,it is shown at ,fig4 #bhi4 ,this frame is not fixed to the base of the poppet1 but pivotted at e1 between two short standards screwed into the poppet for that purpose4 ,when not in use1 the whole frame1 therefore1 drops down towards the front1 but it can be raised by the small cam1 ,k1 ,fig4 #bhi1 so as to gear with the worm wheel4 ,in many cases the latter is not used1 but the pulley turned by hand4 ,the screw1 however1 gives a steadier and more easily regulated movement1 essential in delicate operations1 and sometimes convenient1 even when the stops do not require to be inserted4 ,the use of the cam1 acting on the frame which carries the tangent screw1 is now generally followed in the eccentric and oval chucks1 and also in the dome chuck4 ,it enables the workman1 by throwing out of gear this part1 to turn the worm wheel with the fingers1 to set it at the required number on the division plate1 a slow process when effected by the screw4 ,illustration3 ,,fig4 #bhg4 ,illustration3 ,,fig4 #bhi4 ,illustration3 ,,fig4 #bhh4 ,,holtzapffel',s ,,rose ,,cutter ,,frame4 ,among the newer devices for ornamental turning1 must be mentioned the rose cutter frame of ,holtzapffel and ,co41 an ingenious adaptation of the principle of the rose engine1 without the drawback of cumbersomeness and costliness4 ,it works like the ordinary eccentric and other cutters by a cord from overhead motion4 ,the apparatus is represented in ,fig4 #bij1 and its various parts in ,fig4 #bia1 c4 ,illustration3 ,,fig4 #bij4 ,illustration3 ,,fig4 #bid4 ,illustration3 ,,fig4 #bia4 ,illustration3 ,,fig4 #bic;,a4 ,illustration3 ,,fig4 #bic;,b4 ,in the first of these figures1 ,a is the shank1 fitting the receptacle of the slide rest1 and drilled to receive a hardened spindle1 at one end of which is a worm wheel1 turned by tangent screw ,b ,c1 and shown again at ,a1 ,b1 ,c1 ,fig4 #bib4 ,by this are turned the parts beyond ,k1 namely1 the frame ,d1 carrying the tool1 as in the eccentric cutter1 adjacent parts ,s1 representing chamfered bar1 ,p1 back plate1 and ,o1 which is a round piece in one casting1 with the back plate1 and having a hole through it for the coiled spring seen between ,o and ,n4 ,all these are secured to the spindle1 and turn together as one piece with it4 ,fig4 #bia is a front view of these parts4 ,h is the back plate of brass1 with steel chamfered bars on its face1 ,e1 ,e1 as in the eccentric chuck4 ,between these slides the plate1 ,d1 ,d1 to the face of which is attached the long steel frame1 carrying the tool holder4 ,close to the letter ,h1 it will be noticed that a slot is cut in the back plate1 through which projects a hard steel pin1 screwed into the back of the sliding plate4 ,this is seen at ,o1 ,fig4 #bij1 and is attached to one end of a coiled spring1 the opposite end of which is secured to a pin fixed in the back plate of this part4 ,the pin ,o1 is thus kept in contact with the edge of the rosette or pattern plate1 ,k1 and1 as the whole turns with the spindle while the rosette is fixed1 the pin1 or rubber1 is compelled to follow the undulations of the pattern1 the motion being1 of course1 communicated to the tool4 ,an inspection of ,fig4 #bid will show the arrangement of the parts on which the rosettes are fixed1 and which is capable of turning1 but does not1 unless the tangent screw and wheel1 ,h1 are brought into requisition1 as will be presently explained4 ,the end of the main shank of the instrument is round1 as seen at ,c1 the worm wheel ,b being screwed fast1 by four small screws1 to the end of the square part of the shank4 ,upon this rounded end fits what may be called the sleeve ,e1 to which is fixed the tangent screw1 and on which also are placed the rosettes4 ,the latter have a large central hole1 ,fig4 #bic1 ,a and ,b1 and fitting closely beyond the screw ,f1 ,f1 of the sleeve1 and1 being prohibited from turning upon it by a small key or feather1 are secured by a screwed ring or ferrule seen at ,l1 ,fig4 #bif1 the edge of which is milled4 ,at ,f1 ,fig4 #bia1 is seen a short stop1 or set screw1 the head of which is divided into ten degrees4 ,by this1 the rubber is prevented from penetrating to the bottom of the undulations on the edge of the rosette1 and1 if it is allowed only just to touch the summits of them1 the tool will cut a circle4 ,thus1 as the screw stop can be accurately set1 one rosette will produce at pleasure graduated waved lines1 the waves growing less and less undulated as the centre 7or circumference7 of the work is approached1 giving a most delicate and chaste pattern1 and chased it certainly is4 ,another variation of the pattern producible from any rosette results from the frame of the tool holder being extended beyond the axis of the spindle in both directions4 ,when the tool is on that side of the axis nearest to the rubber pin1 the undulations of the rosettes will be so followed as to produce their exact counterpart on the work4 ,when the tool-holder is on the other side of the axis1 the undulations become reversed1 the raised parts of the rosettes producing hollows and vice versa4 ,it may here be mentioned that in the case of the rose cutter1 eccentric1 and universal cutter1 and similar apparatus1 the screw heads carry ten chief divisions and ten smaller divisions4 ,the screws are cut with ten threads to the inch1 so that one turn advances the slide1 or the tool1 or wheel as the case may be1 one-tenth of an inch4 ,one large division1 therefore1 produces a movement equal to one-hundredth1 and one small division one two-hundredth of an inch4 ,if the screw is small it is generally cut with a double thread equal to one-twentieth of an inch4 ,it is evident that in addition to the movements of the various parts of the rose cutter1 the turner also has in his power those of the slide rest1 and of the division plate on the lathe pulley1 by one or both of which further complications become possible4 ,six modifications of pattern produced from one rosette alone are shown in ,holtzapffel and ,co4's catalogue1 and these may be further multiplied according to the taste and skill of the operator4 ,it is not possible to apply rapid movement to this rose cutter1 else the rubber would probably miss touching the rosette in places2 hence the tangent or worm wheel is used to give motion to the central spindle4 ,an end view of this is given in ,fig4 #bib4 ,the object of the other tangent screw is1 to move the sleeve and therewith the rosette at pleasure1 so that the higher parts of the undulations in the second cut may1 if desired1 be arranged to meet the lower parts of the same in the first cut or to fall intermediately4 ,the effect of the gradual shifting of the rosettes in this way is perfectly marvellous1 and the writer much regrets that he is unable to supply specimen plates1 as he is not in possession of the rose cutter4 ,in the end of ,holtzapffel's latest edition of his catalogue are several such specimens1 but without any drawing or description of the instrument1 the cost of which is moreover omitted4 ,illustration3 ,,fig4 #bib4 ,the centres of circles cut by this eccentric tool will be always regulated in regard to position by the slide rest1 because these centres are1 as explained1 always in a line with the centre of the spindle4 ,hence1 to place a circle in any desired position1 it is only necessary to determine its centre1 and1 after drawing back the tool by means of the screw till its centre runs truly as a mere drill1 turn the screw of the slide rest until the point touches the required spot4 ,,universal ,,cutter ,,frame4 ,this is represented in ,fig4 #bhd1 in its latest improved form4 ,it consists of a shank1 ,a1 which fits the tool receptacle1 and is bored throughout its length for the reception of a central steel spindle1 to which is securely attached at one end the worm wheel1 ,g1 acting as a dividing plate1 and at the other the crank-formed frame1 ,b1 ,c1 with its small poppets1 ,d1 ,d4 ,these are sawn lengthwise1 and thus spring upon the centre screws1 which pass through them and carry the revolving cutter spindle1 ,k1 ,l1 ,m1 in the centre of which is a slot to receive the tool1 the latter being clamped by the tightening screw1 ,l4 ,there are certain points to be attended to in the construction of this instrument1 which must on no account be neglected4 ,in the first place1 the screws which pass through the poppets must lie in the line which would bisect at right angles that of the main spindle in the same plane4 ,a line1 in fact 7as dotted71 passing from screw to screw will pass across the centre of the end of the spindle4 ,in the next place1 when the tool-holder1 with its pulleys1 is in place between ,d1 ,d1 this line must be even with the top line of the central mortise1 ,h1 for the point of the tool is level with its upper surface1 it being bevelled below2 and it is essential that this point be capable of being so placed as to form a continuation of the centre of the main spindle4 ,at ,e1 ,e1 are shown two of four thin pulleys4 ,the two front ones are removed to show the poppets4 ,they should not be made thicker than necessary1 in order to avoid their interfering with the action of the tool4 ,either pair will be used with either pulley1 ,k1 ,k1 according as the right or left side of the instrument is the highest1 for1 as will be explained1 the cutter frame is used at all angles between the horizontal and the vertical lines1 the cuts being consequently inclined in either direction1 left1 or right1 at pleasure4 ,the centre screws and points of the tool spindle must be carefully hardened4 ,before commencing to use this cutter1 it is necessary to test the centrality of the point of the tool4 ,place the latter in its holder4 ,let the part ,c of the instrument be turned till vertical2 cause the tool to revolve and to cut a light line or scratch on the face of the work4 ,by means of the tangent screw cause ,c to become vertical in the opposite direction1 so as to bring the other pulley upwards1 and with the small screws in the poppets set the revolving tool holder1 till the tool falls exactly on the line first made4 ,it is1 of course1 understood that the line in question passed through the centre of the work4 ,if in both positions of the tool the central point is passed through1 the cutter tool is correctly placed4 ,the poppet screws are for this purpose specially1 though sometimes used to place the cutter purposely above or below the centre of the work4 ,compared with the old form previously given1 this pattern of universal cutter is very superior4 ,illustration3 ,,fig4 #bhd4 ,,rose ,,engine4 ,the rose engine1 as hitherto constructed1 has not been entirely supplanted by the neat little apparatus already described1 but is still used almost universally by the watch case makers2 and its construction differs little1 if at all1 from that described by ,bergeron2 although the slide rest used with it is somewhat modified and improved4 ,there are two kinds of rose engine1 in one of which the mandrel with its poppets and fittings oscillates between centres fixed beneath the lathe bed2 while in the other1 the frame carrying the slide rest is thus movable1 the mandrel head remaining stationary as in an ordinary lathe4 ,in both cases the mandrel is allowed a to-and-fro or pumping movement in its collars2 as the rosettes used are cut upon the face as well as upon the edge2 and the rounded parts of an article can be operated on as well as the plane surfaces4 ,the second pattern1 in which the poppet remains a fixture1 will be first described1 because it is capable of being applied to an ordinary lathe for surface work1 and if the lathe has a traversing mandrel1 it can be completely fitted for rose work4 ,the drawings and description annexed are from ,bergeron's work2 but the slide rest there represented1 and arrangement of screwed mandrel1 are omitted as obsolete3-- ,a strong iron frame1 ,a1 ,a1 ,figs4 #bie ,a1 #bie ,b1 and #bif1 is made with one of the ends carried up and branched1 so as to embrace the mandrel and rosette2 which latter is attached to the back part of the chuck which carries the work4 ,the top of the frame is double1 so as to form of itself a lathe bed of small dimensions1 upon which an ordinary slide rest can be fitted4 ,it must1 however1 be used with a short socket1 or it will be too high2 as the top of the frame alluded to stands slightly above the level of the bearers4 ,b1 is a point of hardened steel which fits into a conical hole in the bottom of the lathe poppet1 or 7if this is not long enough to reach a good way down between the bearers7 into a piece of iron arranged for the purpose similar to that now to be described1 and which is again shown in ,figs4 #big and #bih4 ,this is a kind of poppet in a reversed position1 the clamping nut and screw being above the bed1 and the head with centre screw below4 ,the frame lies1 therefore1 between the mandrel head and this reversed poppet1 or between two of the latter1 and oscillates upon their centres whenever the projections or depressions of the rosette compel it to assume such motion4 ,illustration3 ,,fig4 #bie;,a4 ,illustration3 ,,fig4 #bie;,b4 ,illustration3 ,,fig4 #bif4 ,fig4 #bii is a section of the chuck which carries the rosette1 the latter being shown in position4 ,a1 is the body of the chuck2 ,b1 the inside screw to fit the mandrel4 ,on the outside of this part are a few turns of a somewhat finer thread1 beyond which a plain part is left next to the flange1 ,c1 and on this the rosette is placed1 and is clamped by the nut1 cut outside into beads1 or milled1 or left plain and drilled for the insertion of a lever pin2 this nut is marked ,d in the figure4 ,it will be seen to lie within a recess formed in the face of the rosette1 ,e4 ,the latter is shown in ,fig4 #cjj4 ,a1 is the recess just alluded to2 ,b1 ,c1 the pattern on the face and edge2 ,d1 the large hole in its centre1 allowing it to be slipped on the back of the chuck4 ,it is prevented from turning on the latter by a pin1 which fits into the small hole1 ,f4 ,from the front face of the chuck rises a conical pin1 ,g1 similar to that on the eccentric chuck1 over which fits the circular division plate1 ,i1 with its projecting screw1 ,h1 to hold the ordinary chucks4 ,this plate is recessed at the back1 leaving a mere ring of metal1 e1 e1 which fits a corresponding circular groove1 and secures the steady movement of the plate1 which is fixed by a conical washer and screw1 as seen in the plate4 ,this division plate is formed with cogs1 into which a stop falls1 as described1 when treating of the eccentric1 but the divisions are differently arranged1 the cogs being divided into sets of eight or ten teeth4 ,let the whole circumference be first divided into six equal parts1 and1 beginning at the first division1 cut six or eight teeth1 as if the whole circle were to be divided into #fj4 ,pass to the second portion1 and cut eight teeth1 as if the circle were to be divided into #gb4 ,let the third carry eight teeth1 with a pitch of #hj to the circle2 the fourth a similar number1 with a pitch of #hd2 the fifth #if2 the sixth #ajj to the circle4 ,these must be cut with the same cutter1 so that the spring click1 or stop teeth1 may fit any of the six sets4 ,there will be several undivided spaces1 which are to be left plain4 ,the several sets are to be marked in numbers1 so that the pitch may be discovered at a glance1 and the teeth in each being so few will hardly require separate numbering4 ,the part of the apparatus which carries the rubber--that is to say1 the heads of the branched part of the swinging frame1 are made flat on the top1 which projects on three sides1 forming small tables on which the actual holder or clamp can be fixed by a turn of the screw1 ,x1 in the first figure4 ,the rubbers are merely flat pieces of steel1 with edges sufficiently sharp to penetrate to the lowest depths of the undulations and recesses on the rosettes1 but rounded off and polished1 so as not to cut and damage the softer metal against which they act2 other materials have been tried1 as ivory1 and the harder tusk of the hippopotamus1 but hard steel is most generally preferred4 ,it is1 of course1 necessary that the rubber press with some force against the rosette1 which force should1 moreover1 admit of being regulated at pleasure4 ,this is effected by a spring of steel under the lathe bed1 to the end of which is affixed the arm1 ,w1 which has a ring handle nearest to the operator1 and is perforated with a row of holes from end to end4 ,this arm is flat1 and falls into a fork at the end of the tail piece1 ,y1 which is seen in the second figure attached to the centre of the lower bar of the frame4 ,a pin passes through holes in this fork1 and through one of those in the arm4 ,by this arrangement it is easy to regulate the force which the spring shall exercise1 as this will be increased by moving the pin nearer to the spring1 and diminished by placing it in a hole nearer to the ring handle4 ,in forming the rosettes great care should be exercised to make the corresponding parts agree4 ,the depth of similar hollows must be precisely equal1 and elevated portions intended to match1 must do so with great accuracy4 ,supposing1 for instance1 a rosette to be made with ten elevations and ten recesses1 all of equal curves4 ,if these are accidentally unequal1 and it is desired to arrange a set of these waved rings one within the other1 so that the depressions of the one shall be opposite to the elevations of the other1 or so that this effect shall take place gradually--if the curves of the pattern are unequally cut the several portions of the device will not tally1 and an irregularity will be produced of disagreeable appearance2 an inspection showing at once that such irregularity is not part of the device1 but unintentional and erroneous4 ,this leads to a consideration of the division plate of this rose engine1 and an explanation of the object of its peculiar construction4 ,the pattern of the rosette is1 as it were1 in sections2 either similar elevations and recesses are alternately repeated1 or there may be a variety of such1 extending over a part of the circumference1 and forming a certain complete device1 which may then give place to a second pattern1 extending a similar distance2 and these two may alternate regularly round the circumference4 ,each of these sections must be of precisely similar length1 and the repetition of the pattern must also be precisely similar1 for the reason stated above4 ,illustration3 ,,fig4 #bii4 ,illustration3 ,,fig4 #cjj4 ,illustration3 ,,fig4 #big4 ,illustration3 ,,fig4 #bih4 ,it is evident that all possible alternations of the device or set of devices may be obtained by means of six or eight notches of the division plate2 for1 by moving it forward to that extent1 the whole pattern may be compassed4 ,in treating of the second form of rose engine1 and of the method of using it1 this will again be adverted to1 and illustrated by an example4 ,hitherto we have spoken only of the use of the pattern on the edge of the rosette1 but1 as already stated1 it is frequently repeated on the face1 and by this means it becomes easier to work upon the outside of a cylindrical piece1 as well as on the two ends4 ,patterns thus cut on the face of a rosette tend1 of course1 to move the mandrel to and fro in its collars1 which is only possible when the lathe is made on the plan of a screw-cutting or traversing mandrel lathe4 ,the spring which keeps the rubber in contact with the face of the rosette is shown at ,p4 ,the head on the top of the arm1 which forms the clamp or holder of the rubber1 must be turned round to face the rosette1 or a separate rubber must be used1 which passes through the clamp at right angles to that used in surface work1 and the frame must be prevented from oscillating by a stop which fits between the bearers of the lathe1 and embraces the upright side of the frame4 ,the top of the slide rest must be turned round1 or a side tool used4 ,in this case1 the rest and frame with its rubber become fixtures1 as in ordinary turning1 the mandrel and work being alone moved in correspondence with the pattern on the face of the rosette4 ,it would indeed be much better to do away with the frame altogether1 fixing the rubber to an upright pedestal mounted on the lathe bed1 and using the slide rest in the usual way1 were it not that in general the work is constantly being varied1 the side and face being worked in turn--and the apparatus is rather cumbrous to remove and re-mount often4 ,it is1 nevertheless1 easy to finish the ornamentation of plane surfaces first1 and then to remove the frame altogether1 and substitute a fixed rubber1 as stated4 ,the rose engine now described has certain evident advantages over the rose cutter frame1 and is capable of the most exquisite devices4 ,it may be1 perhaps1 a mere question of taste1 whether rose engine work finely executed is not in point of beauty1 superior to any that can be done by geometric chucks1 however elaborate4 ,that it is so1 is decidedly the writer's opinion1 more especially when this apparatus is used in combination with the oval chuck4 ,moreover1 there is nothing in the form of rose engine described to make it a very expensive article1 or beyond the skill of an amateur2 and with a set of only three rosettes1 the patterns may be varied continually1 and multiplied--if not ad infinitum--yet quite sufficiently for the display of skill and taste of the operator4 ,in using the rose engine1 it is necessary to carry the cord to the pulley from a very small wheel on the axle4 ,sometimes the lowest speed pulley of the flywheel may answer1 but if the recesses of the rosette are deep and sharp1 or only slightly rounded1 it may become necessary to mount a still smaller wheel on purpose2 else the rubber will jump over and miss parts of the design1 thereby spoiling the work4 ,the watch-case turners1 indeed1 altogether dispense with the flywheel1 and use instead a small pulley1 fixed to the side of the lathe bed1 and turned by hand4 ,these artificers always use a more elaborate form of rose engine1 which will be presently described1 and which is the most perfect in detail of all similar contrivances1 but it is necessarily costly1 and cannot be said to be well adapted for plain turning also1 except in a limited degree4 ,the work1 if not of soft material1 like a watch-case1 should be turned first of all upon an ordinary lathe1 the mandrel screw of which is a counterpart to that of the rose engine1 and the latter should merely be used for the final cut1 to perfect the form of the material previous to its ornamentation4 ,in the ,appendix will be found a new method of obtaining the required oscillatory motion of the rose engine1 which might apparently be applied to tool holder#bb frame here described1 or to the poppet head4 #bb ,i4e41 the main frame carrying the slide rest4 ,the rose engine proper is arranged with an oscillating poppet head carrying the mandrel and its rosettes1 the tool being stationary4 ,the following account of this machine1 and the drawings1 are copied almost exactly from ,bergeron4 ,the modern rose engine is not indeed made with the projecting lugs referred to as intended for the application of the guide ring in oval turning1 as this guide is now altered to fit a poppet head of ordinary form1 as already detailed4 ,the pulley and division plate are also of obsolete form1 but as the main arrangement of parts described are sufficiently similar to that now followed1 ,bergeron's drawing and description have been retained4 ,fig4 #cjb is a longitudinal view1 and ,fig4 #cjc a transverse view of the working parts of this lathe4 ,a1 ,a are the poppets1 which are in one casting1 with the connecting piece shown by the dotted lines1 which latter has a tail piece firmly attached to its centre1 to which a spring is affixed as in the lathe previously described4 ,in the drawing the cylindrical collars carrying the mandrel are split1 so that in case of wear they can be tightened in the usual manner by a screw at the top of the poppet marked ,b1 #cjc4 ,the lugs1 f1 f1 with square holes e1 e1 are for the application of the guide for oval turning1 the latter being originally a ring with slotted arms on either side4 ,the points of oscillation are precisely similar to those of the rose engine first described1 two short poppets ,c1 ,figs4 #cjb and #cjc1 having centre screws1 whose points fall into conical holes made in opposite faces of the poppet1 a little below the level of the lathe bed4 ,these are formed with a slit to receive the stop h1 which is hinged at the point o1 and which1 when raised by a wedge1 catches into a small projection p1 thereby fixing the poppet in a perpendicular position and preventing its oscillation4 ,the rose engine can then be used as an ordinary lathe1 to finish the preparation of the work to be operated on1 which should1 if possible1 be commenced and mainly formed on an ordinary lathe1 the mandrel of which is a counterpart of that of the rose engine4 ,the tail piece1 ,e1 does not require a separate description1 being precisely similar to that already described4 ,the to-and-fro movement of the mandrel caused by the action of the rubbers on the face of rosette1 is also arranged in a manner similar to the last4 ,f is the spring1 turning in the middle of its length on a pin in a piece of iron fixed on the bed1 so that if both ends wore free it could swing backwards and forwards between the cheeks of the lathe on this pin as a centre4 ,the upper end of this spring is branched in a semicircular form to embrace the mandrel1 this fork falling into a groove formed to receive it4 ,it can thus be brought to bear against either of the shoulders visible at this part4 ,the lower end of the spring fits into a notch1 or rather a slot in the arm ,h of the second figure2 the handle of this arm being ,l in both figs4 ,this piece is pivotted at ,k1 and at its other end falls into one of the notches in the retaining plate1 ,g1 of the first figure4 ,by this plan the tension of the spring1 can be brought against the mandrel in either direction at pleasure1 for if the lever is placed in one of the left hand notches1 the tendency of the spring will be to move the mandrel towards the right1 and vice versa4 ,the tension of the spring can also be regulated by the use of the groove ,b or ,x at pleasure4 ,in the second figure of ,bergeron's the piece which at first sight appears to be a continuation of the holding down bolt of the short poppet carrying the centre screw1 is the tail piece or lower end of the long spring just described1 and its reduced extremity is visible passing through a short slot in the lever ,h1 near the handle of which appears the edge of the notched piece ,g of the other figure4 ,all the above parts are commonly of iron1 the following are in brass or gun metal4 ,illustration3 ,,fig4 #cjc4 ,illustration3 ,,fig4 #cjd4 ,illustration3 ,,fig4 #cjb4 ,on the bed and parallel to it1 two pieces of brass1 or standards1 rise1 similar to ,h in the first figure1 the two being opposite to each other1 one on each side of the mandrel1 as shown in the second figure4 ,both these are firmly secured to the bed by long bolts and nuts1 it being of the utmost importance that they should not move or vibrate in the least4 ,they are in addition united to each other by two horizontal braces1 one of which is seen at ,n in the second figure4 ,at l1 l are seen two rectangular notches1 which are the ends of grooves made in the upper part of the head piece1 ,h1 and which traverse its whole length4 ,they receive the crooked part1 a1 of the rubber holder1 ,fig4 #cjd1 so that the latter can be slid along this bar1 and brought opposite to any one of the rosettes1 after which it can be secured in position by the screw1 b1 ,fig4 #cjd4 ,the mandrel is thus arranged4 ,it is cylindrical1 with a shoulder against which the chucks can rest1 as in an ordinary traversing mandrel1 and a similar but reversed shoulder at g1 ,fig4 #cjb4 ,against the latter abuts the end of an accurately turned sleeve of brass1 which fits over the mandrel with slight friction1 so as to have no shake or play upon it4 ,upon this sleeve the rosettes are placed4 ,they fit accurately over it1 and are prevented from turning round upon it by a feather extending the length of the sleeve1 which fits into a corresponding notch cut on the inside of the rosettes4 ,these are arranged in pairs back to back1 and each couple is separated from the next by a short sleeve or ferrule1 which ,bergeron recommends to be of wood1 as tending to hold the rosettes more securely than metal when pressed together by the nut at the end of the set4 ,the fibres of the wood are to be placed parallel with the mandrel1 because there is no shrinkage of this substance as regards its length4 ,the pulley is fixed beyond the rosettes on a part of the mandrel filed into six faces for that purpose1 and lastly comes the nut1 which secures all the parts to their several positions1 but which nevertheless does not so jam them together but that the mandrel can be turned within the sleeve when the positions of the rosettes are to be changed in the course of working a pattern4 ,the division plate is not attached to the pulley1 though lying close upon its surface4 ,it slips on to the sleeve on which the rosettes fit1 and its spring-catch only on the face of the pulley4 ,thus the latter is held to the sleeve and its fittings when the catch is down1 so that all turn together1 but1 when the catch is raised1 the division plate1 carrying with it the rosettes1 can be turned round upon the mandrel as may be required4 ,it is not necessary to repeat what has been said respecting the manner of graduating the division plate1 as that used with the lathe already described is in that respect a counterpart of what is used with the rose engine now treated of4 ,illustration3 ,,fig4 #cje1 #cjf4 ,illustration3 ,,fig4 #cjg4 ,the following description of the method pursued in turning a pattern shown in ,fig4 #cjg will suffice to show the working of the rose engine3--,first1 says ,bergeron3--,it is not enough to know the general construction of the rose engine1 it is necessary to know thoroughly the particular one in use1 i4 e41 as regards the details of its construction1 the slight defects or imperfections it may chance to have1 and the means whereby they may be lessened or corrected4 ,it is necessary1 in addition1 to know well1 and to have always at hand1 the numbers of each rosette1 or any rate to have a table of them which can be readily referred to4 ,it is equally necessary to recognise at a glance the various sets of divisions on the division plate1 for which purpose1 and that no mistake may be made1 such numbers ought to be engraved upon each4 ,the same holds good with regard to the slide rest1 and1 in addition1 practice should be frequent upon box or other inexpensive material by which the turner may have made himself perfect in the several combinations possible1 and the various effects producible by the rosettes and different shaped tools over which he has control4 ,it is thus1 by actual experiment only1 that the turner can become acquainted with the powers of his own lathe and apparatus1 and thus only1 after working out the patterns already executed1 will he be in a position to design new ones1 and to work with ease and certainty4 ,the rose engines are usually fitted with tools of variously shaped edges1 as shown in ,figs4 #cje and #cjf1 by this means a pattern of some width and great variety is of course produced at once1 and by one rosette4 ,in the following1 however1 a tool with single point1 ,fig4 #cjh1 is to be used4 ,this simplest design is supposed to be on the cover of a box or other plane surface1 and it is evident that the movement or oscillation required of the mandrel is that at right angles to the bed of the lathe4 ,to obtain this movement1 when the rubber is fixed in its clamp1 on the side of the workman1 as it is necessary that the rubber should press against the rosette through the medium of the spring1 the handle of the lever1 ,fig4 #cjb1 must be drawn forward towards the operator1 and kept by a pin1 as described1 passing through it and the tail piece of the mandrel frame4 ,the tension must not be too great1 especially if the rosette to be used is deeply indented1 and care must be taken to free the frame from the action of the stop1 p1 by removing its wedge before making any attempt to try the pressure by moving the mandrel4 ,the design under consideration is produced from rosette numbered #b in the drawing1 and in fixing the rubber care must be taken that it does not bear against the adjacent rosette4 ,choose a rosette of forty-eight teeth or undulations1 and as the second circle of ornamentation exactly intersects the first1 the raised part of the one falling under the depression of the other1 and as it were halving it1 the set of divisions on the click plate to be used will be twice #dh1 or #if4 ,place the rest parallel to the face of the work and so that the forward motion of the tool shall be perpendicular to it4 ,by means of the leading screw of the rest1 place the tool near the edge of the work and level with the centre1 and gently moving it forward and putting the lathe in motion1 commence the cut4 ,after having made a light cut1 without moving the tool1 stop the lathe and judge of the depth of cut1 and if sufficient1 screw up the stop screw of the slide rest1 to insure all the following cuts penetrating to the same depth4 ,observe the position of the tool as marked by the graduations of the slide rest1 and then withdrawing it from the cut1 move the click plate one notch1 which will divide exactly in half the several undulations of the rosette4 ,by the rest screw move the tool towards the centre of the work and mark the number of divisions passed over1 so that the circles of undulations may be equidistant1 and cut a second4 ,now for the third1 go back or advance on the click plate one division1 for the position of the undulations in the third is precisely that of the first circle4 ,it is indeed immaterial whether an advance or retreat of one notch is made in this case1 but now is evident the reason for not dividing the plate equally all round1 five or six teeth being ample for each division4 ,if there are eight rosettes the plate should be first divided into eight parts1 and each rosette having a different number of undulations1 these eight parts should be divided into degrees proportionate to the numbers on the rosette1 the one being a multiple of the other4 ,in working the side of a cylinder1 that of a box1 for example1 the longitudinal movement of the mandrel is required1 the poppet being retained immovable by the wedge and stop4 ,the tool is to be placed at right angles to the side of the work1 the rubber brought to bear on the face of the rosette4 ,the method of working will be self-evident1 after the description already given4 ,it is impossible in a brief work like the present1 to go into details of other patterns referred to and illustrated by ,bergeron1 one or two of which are nevertheless of great beauty1 and are executed with the aid of the eccentric chuck mounted on the mandrel of the rose engine4 ,there is1 however1 a different class of work1 to which reference will be made in our next1 and we shall also give a description of a simple addition to the slide rest1 used by watch case turners1 which does away with the necessity of counting the number of divisions upon this instrument when used as above4 ,the slide rest used by the watch case turners is almost identical in form with one figured and described by ,bergeron4 ,it is necessary that the tool holder should have a circular motion1 somewhat similar to that of a spherical rest1 in order to reach the sides and curved surfaces of the articles to be engine turned2 hence the tool receptacle and its bed work upon a central pin4 ,the pin here called the bed is usually a flat brass plate of a quadrant form1 the central pin being at the apex1 and carrying on its face the guides for the tool receptacle4 ,the pin on which it turns is a reversed truncated cone rising from a similar flat plate1 which itself forms the sole of the rest1 or traverses the lower frame as usual2 when the tool is beyond the central pin1 it will ornament conical surfaces1 and vice versa4 ,on the edge of the arc is a racked part1 and a tangent screw works into it4 ,the tool is moved to and fro by a lever1 as usual1 the depth of cut being regulated by a stop screw4 ,these details being already entered into1 in treating of slide rests and chucks1 need not be more specially explained here2 but a contrivance for regulating the traverse of the upper part upon the frame underneath1 is ingenious and serviceable1 and will therefore be described4 ,the end of the leading screw is fitted with a ratchet wheel of the same construction as that of the ratchet brace for drilling1 patented by ,fenn1 of ,newgate ,street1 to which in the same way a handle and spring are attached1 as shown in the drawing1 ,fig4 #cji1 ,a1 and ,fig4 #caj4 ,the handle rises between two semicircular plates drilled in the face1 with holes for the reception of stop pins1 ,b1 ,c4 ,these regulate the traverse of the handle1 and thence of the screw4 ,if the former1 therefore1 is thrown over till the left stop is touched1 and then pulled forward to the other stop1 between each cut of the tool1 the latter will leave equidistant spaces upon the work1 without need of counting divisions at each cut4 ,as a traverse of one inch or more of the lever handle at the place of the stop pins only moves the screw a very minute quantity1 the holes for the pins need not be very close together even for fine work4 ,this is a very simple contrivance1 and perfect in action1 enabling the operator to work with ease and certainty1 and with great speed4 ,illustration3 ,,fig4 #cji4 ,illustration3 ,,fig4 #caj4 ,,rectilineal ,,chuck4 ,fig4 #caa represents a modification of the eccentric chuck1 when the latter is used as a fixture1 to present to revolving cutters and drills the different parts of the work which is to be operated on4 ,the eccentric chuck is commonly made to slide in one direction only1 and the traverse is limited4 ,in the present case there is ample traverse in both directions1 the slide being arranged to descend to the lathe bed1 and upwards to an equal degree4 ,a is a cross section of this chuck1 the length of which is #g-a_/b inches4 ,it is very strongly made in brass1 and is altogether much more substantial than the eccentric chuck4 ,b and ,c are the guide bars1 between which works the sliding part4 ,the nut of the leading screw is below this as usual4 ,the tangent wheel has #abj teeth1 and is thus divided3 #j--ab--bd1 c4 ,the tangent screw head is divided thus3 #j--a--b--c--d--e1 with half divisions1 marked but not numbered4 ,this rectilineal chuck is most commonly used in a vertical position1 but may be otherwise placed4 ,in using it for any work likely to bring a strain upon it1 the ordinary spring index attached to the lathe for use with the face plate1 should not be entirely relied on to keep it in position4 ,it is safer to make use in addition of the segment engine stops or other available contrivance4 ,the special function of the chuck is the production of straight lines on the face of work forming stars or radial flutes1 which can be worked with a drill4 ,fluting is also readily done by its aid1 with the addition of the vertical eccentric1 or dome chuck1 already described4 ,its use is1 however1 by no means confined to ornamental work--small tenons1 mortises1 and even dovetails are producible by it2 and in fitting together the various parts of temples1 shrines1 and similar complicated specimens1 its uses will be innumerable2 and here may be noted the extension of the lathe and its apparatus to work apparently in no way suited to it4 ,it has now become more of a universal shaping machine than it used to be1 owing to the great accuracy of the work done by it1 and the variety of fittings that can be added to it4 ,in a later page will be found a drawing and description of a new device of the kind--a planing machine1 devised by an ingenious and first-class maker1 ,munro1 of ,lambeth1 and patented by him4 ,mention is made of it in this place1 because the rectilineal chuck is in some degree capable of similar work4 ,the slide moved up and down by a screw the handle of which is of extra length to allow the vertical traverse1 is also capable of being moved by a cam-eccentric chain or rack and cogged wheel1 so that by pulling down a handle the slide may be made to slide up and down more rapidly than by the screw motion2 any piece of wood of rectangular or other figure may thus be planed on the face1 by being fixed on the rectilineal chuck1 and acted upon by a fixed tool in the slide rest1 the latter affording the horizontal traverse of the tool across the face of the work1 the former the perpendicular movement of the material4 ,if a slide rest is thus arranged in combination with the chuck in question1 and the lathe bed is imagined to be set up on end with the chuck downwards and horizontal1 the whole will become1 in fact1 a precise counterpart of those planing machines1 the bed of which traverses to and fro1 with the work under a fixed tool4 ,munro's arrangement is1 of course1 of far more extended application1 and more suited for metal work2 but for lighter and more delicate operations of a similar kind the rectilinear chuck and slide rest will be found very serviceable4 ,it is with such an adaptation of this chuck as has been alluded to1 namely1 a quick speed movement of the slide by a lever handle1 that the rays are drawn so exquisitely fine and close upon the faces of many gold dial plates of watches1 the handle being arrested by a stop at any given point1 so that these rays shall not transgress their appointed limits4 ,it will be hardly necessary to allude to those other applications of this apparatus1 or other particulars in which it is identical with the eccentric chuck1 as the description already given of the latter applies to both alike1 the extra traverse of the present in both directions being its chief distinguishing feature4 ,illustration3 ,,fig4 #caa4 ,illustration3 ,,fig4 #cab4 ,,epicycloidal ,,chuck4 ,this chuck has been in use for many years1 and has in consequence been of late rather neglected4 ,it is1 nevertheless1 the parent of those more elaborate contrivances included under the general title of ,geometric ,chucks1 of which ,ibbetson's stands first in order of date1 and possibly of merit1 though this last qualification may admit of question4 ,the epicycloid1 defined mathematically1 is a curve described by the revolution of a point in the circumference of a circle1 when the latter is made to roll upon the concave or convex side of another circle4 ,a pin in the rim of a wheel revolving round and in contact with another wheel1 therefore1 describes this curve1 which constitutes two or more loops1 as will be seen by the annexed illustrations4 ,the number of these loops is variable1 and the chuck will produce almost any number by changing the pinions1 and thus altering the relative velocities of the revolving parts4 ,the following description will make the action of this chuck clear1 and enable any good mechanic to construct one for himself4 ,in the first place1 the above remarks show a necessity for a fixed wheel1 round which another may revolve4 ,fig4 #cac represents this attached to a plate of brass1 which can be fixed to the lathe head1 the mandrel passing through its centre4 ,this is the original pattern of plate1 and need not1 of course1 be adhered to1 as the form can be modified to suit the lathe to which it is to be applied4 ,it is merely necessary to affix such a wheel to the face of the poppet1 so as to be concentric with the mandrel a plan done away with1 however1 or rather reversed1 in ,plant's geometric chuck4 ,the epicycloidal chuck1 which screws to the mandrel as usual1 consists of a foundation plate of brass1 ,a1 ,fig4 #cad1 behind which is mounted the cogwheel1 ,b4 ,the axis of this wheel passes through the plate1 and is carried by another plate1 e1 which is curved and adjustable upon the former4 ,the axis of this wheel carries a small pinion1 ,d1 so that the whole turn together4 ,this pinion being one of a set of change wheels1 necessitates the possibility of adjusting the plate which carries its axis1 as all the several change wheels must gear with ,e1 which always retains its position on the chuck4 ,the sliding plate in question being put in place1 is clamped by the screw ,f4 ,a plate of iron1 ,g1 of the form shown1 and of sufficient thickness for the secure attachment of the wheel and of the screw which carries the ordinary chucks1 is fitted to turn on the axis of the wheel ,e4 ,its larger end traverses within the arc ,h1 which is graduated4 ,the arc is bevelled underneath1 serving to hold down securely to the foundation plate the piece of iron which is chamfered to fit it4 ,at the left side of the back plate is seen a stop1 ,l1 which is placed in such a position1 that when the iron plate rests against it1 the screw ,m is concentric with the mandrel1 and work may be turned as upon an ordinary chuck4 ,to throw the iron plate1 and consequently the nose of the chuck1 on one side1 or in other words to place the work eccentrically1 the screws which retain the arc are loosened and the adjustment made by hand4 ,the eccentricity is marked by an index on the iron plate1 which points to the graduations seen upon the face of the arc4 ,the eccentricity being determined1 the arc is again screwed down to retain the movable plate in its new position4 ,although this is ,bergeron's method1 it appears vastly inferior to the plan of racking the edge of the iron plate1 and moving it to any required degree of eccentricity by the aid of a tangent screw4 ,when made as above1 the chuck will produce loops varying in number according to the relative dimensions of the pinion 7or change wheels gearing with ,e7 and the central wheel1 ,m4 ,if the latter has #abj teeth1 and the change wheel #fj1 two loops will result4 ,if the pinion has ten teeth1 the number of loops will be #ab1 and so forth4 ,the practical limit to the number depends on the possibility of diminishing the pinion in size and number of cogs1 and still keeping the latter of such size and pitch as to gear with ,e4 ,if1 therefore1 a larger number of loops is required than can be obtained thus1 it becomes necessary so to modify the form of chuck as to permit of intermediate change wheels1 and when the modification is carried out1 we have the geometric chuck1 the most perfect1 but the most complicated and expensive of all4 ,to understand the nature of the work1 the following is given in clear language by ,bergeron1 and will sufficiently explain and simplify matters4 ,illustration3 ,,fig4 #cac4 ,illustration3 ,,fig4 #cad4 ,illustration3 ,,fig4 #cae4 ,if one considers the movement of the piece 7of work7 when the wheel ,m is concentric with the mandrel1 it will be perceived that although it makes two revolutions upon its axis1 yet inasmuch as it has no eccentricity it will describe no particular curve or figure2 but if an eccentricity of three divisions is given to it1 two buckles or loops will result as in ,fig4 #cae4 ,before cutting the material1 however1 approach the tool as near the work as possible1 and putting the lathe in motion1 observe whether the buckle#bc passes too near the centre or too far from it1 and also how near it goes to the circumference4 ,if another change wheel with forty teeth instead of sixty is substituted1 the slide ,c1 being adjusted accordingly1 three loops will be described 7forty being one-third of one hundred and twenty71 but it is always necessary before actually cutting the material1 to try whether the buckles will pass near to the centre without going beyond it4 ,the result of the latter movement will be shown presently1 as it entirely alters the appearance of the pattern4 ,the divisions commence on the arc at the left hand1 the index resting at #j when the plate is against the stop ,l1 and the screw of the chuck concentric with the mandrel4 ,the preceding figure of three loops will become similar to ,fig4 #cag1 retaining the same wheels and some degree of eccentricity1 but by means of the slide rest moving the tool towards the circumference1 so that the buckles overlap the centre4 ,the effect thus produced is1 that of a set of three curvilineal triangles of which the apex of one falls upon the base of the next4 ,the use of this chuck is stated to require upon the part of the operator more care than any other1 as regards the derangement of work or tool in the least during the operation1 as1 if either is once moved in the least out of position1 it will be found next to impossible to strike the line again1 owing to the peculiar nature of the curve1 for although the tool may be replaced upon any one part of the line already cut with the intention of deepening--it is by no means certain that it will trace the same curve again4 ,this curve1 says ,bergeron does not produce an agreeable effect on the cover of a box1 unless it is very finely cut1 the tool1 therefore1 should be very sharp in the angle and very keen4 ,bergeron specially mentions this in reference to filling the cuts with thin strips of horn or shell1 a method of inlaid ornamentation not much known or admired in the present day1 but to which allusion may probably be made again in this series4 ,to form the second set of loops1 which are parallel with the first in these designs1 it is only necessary to use the leading screw of the slide rest1 to move the tool nearer to or further from the centre1 while the eccentricity and the arrangement of change wheels remain as before4 ,it is scarcely necessary to detail the formation of the larger series of four loops and upwards1 as these are simply the result of different sized change wheels3 the following principles1 however1 by which the buckling of the several loops is controlled or prevented1 may perhaps be serviceable4 ,when1 for example an eccentricity of sixteen divisions is used--if the tool is placed at a distance of two such divisions from the centre of the piece1 a line only will be produced of as many curves as the wheel or pinion ,d would produce buckles4 ,if the tool is moved further from the centre by a quarter division1 the angles 7connecting the curves7 will be more defined1 but still no buckles will be made4 ,a little further movement of the tool will produce very small buckles which will thus gradually increase as the tool is set further and farther from the centre--until at last when the curves pass beyond the centre1 the result is arrived at already shown in ,fig4 #cag4 ,another form of this chuck is shown in #cah1 in which1 instead of the iron plate being pivotted for the purpose of eccentricity upon the axis of the wheel ,e1 a parallel slide motion is given to the main wheel by guide bars1 as in the eccentric and oval chucks4 ,this form is figured in ,lardner's ,cabinet ,cyclopdia4 ,the large front wheel carrying the screw for chucks is pivotted to the slide ,c1 and protected by a plate ,d which nearly covers it4 ,the wheel ,l1 is arranged to follow this slide1 so as to remain in gear with the large wheel without leaving the fixed wheel or ring on the face of the poppet4 ,in both patterns of this chuck the front wheel is used as a division plate1 being moved in either direction as many cogs as desired to produce interlacing of the looped designs4 ,it is better1 however1 to add a racked division plate and tangent screw1 as in the eccentric chuck to act as one piece with the chuck screw1 and with the latter turning on a conical pin in the centre of the large wheel underneath4 ,the above apparatus requires to be used with a slow motion owing to the complication of parts1 and the whole ought to be so well constructed1 that the various wheels revolve with perfect smoothness and without shake or noise4 #bc ,the word buckle is used to signify the small loops--not the large curves4 ,illustration3 ,,fig4 #caf4 ,illustration3 ,,fig4 #cag4 ,illustration3 ,,fig4 #cah4 ,,the ,,spiral ,,chuck 7,,fig4 #cai74 ,there is no class of work on the whole more interesting than that executed by the aid of the spiral chuck1 especially with an addition to be described here4 ,this apparatus has grown1 almost as a matter of course1 from the adaptation to the ordinary lathe of the system of change wheels for the production of screws of various pitches4 ,a spiral is1 in fact1 a screw with very extended pitch1 the threads either closely enwrapping a cylinder which forms the core or body of the screw1 or being entirely separate and independent of such core1 the latter being by far the most light and elegant4 ,the chuck here described is used with the same arm or bracket as has been already spoken of1 standing out from the poppet to carry change wheels1 and is itself adjustable to suit different diameters of the same4 ,in the sectional view of this chuck given here1 ,a1 ,h1 is the body with internal screw as ,b1 to fit the mandrel4 ,the cog wheel of the chuck which gears into the first on the movable arm or standard1 is cast with a large central hole to allow it to be stopped on at ,d1 where it is retained by a nut ,c4 ,this permits a change of such wheel for one of different size or for the apparatus to be presently described4 ,thus far the chuck is only applicable to the production of screws or spirals with a single thread4 ,f1 is a dividing plate with racked edge acted on by the tangent-screw ,e1 and carrying the screw1 ,g1 a counterpart of that upon the mandrel4 ,this plate carries #if divisions or teeth4 ,the latter may be used with a spring click if preferred2 but the racked edge gives perhaps the more delicate power of adjustment4 ,the spiral chuck constructed in this way is capable of producing any required number of screw threads or spirals1 solid or detached1 and of any ordinary pitch4 ,it is1 however1 chiefly intended for the production of spirals or twists for articles of virtu4 ,the method of proceeding has already been described in a previous page4 ,it is one rather of care than skill1 as the lathe apparatus ensures the correct movement of the tool where the shape of the latter determines the form of thread1 angular1 round1 or moulded at pleasure4 ,a few of the tools required are shown in the drawing4 ,for finishing the rounded threads1 ,nos4 #c and #d may be used1 which are similar to those required for turning ivory rings1 the one completing half the thread1 the other applied in the opposite direction1 meeting the cut of the first and finishing the operation4 ,as it is necessary to get round to the back of the threads in this case1 no inner mandrel can be used to support the work1 and1 therefore1 great care and delicate handling are necessary to prevent breaking the twists4 ,the stops should also be used upon the bed of the slide-rest1 to limit the traverse of the tool and prevent it from striking the shoulder1 and destroying any bead or other moulding formed there4 ,this is more specially needed1 when there are two or more such twists rising from the same base 7that is when there are two or more threads to the screw74 ,the additional apparatus now to be described1 adds considerably to the powers of the spiral chuck4 ,it is called the reciprocating apparatus1 and its effect is1 to cause a to and fro movement of the work1 at the same time that the motion of the tool is continued in a horizontal direction4 ,fig4 #cbj shows the simplest of the effects thus produced4 ,the screw is commenced and carried to any desired distance on the cylinder4 ,the action and horizontal traverse of the tool is continued1 but that of the cylinder reversed1 and the cut is thus carried upwards4 ,the tool may be a revolving cutter1 the action of which1 being continuous and in the same direction1 would seem preferable1 as the greater the speed with which the tool attacks the material the better is generally the result in work of this kind4 ,a fixed tool1 moreover1 must have a central edge chamfered above and below1 and there is also a tendency with any such fixed tool to unscrew the chuck1 as the resistance occurs in that direction in the upward cut4 ,illustration3 ,,fig4 #cbj1 #cba1 #cbb1 #cbc1 #cbd1 #cbe4 ,the details of the arrangement are as follows3--,the several parts being drawn of full size1 ,fig4 #cba ,a is an eccentric capable of slight adjustment by the use of either hole1 one being further from the centre than the other4 ,fig4 #cbb gives another view of this eccentric1 which is precisely similar to that used in model engines4 ,it is turned as a circular plate of gun-metal1 with one flange4 ,the plate being five-tenths of an inch thick1 a second plate1 forming another flange1 is attached by four small screws1 after the ring of the eccentric is in place4 ,this ring is of iron1 or1 still better1 of steel1 and is made in one piece1 with the arm ,b1 which is six inches long2 the main part of it is flat1 but it is rounded towards the end1 and turned at ,e1 after which it is again flattened to work against the arm ,d1 or still better forked to embrace the latter4 ,it will be seen that ,d is also a flat plate1 with a turned ring similar to the first1 but without the enclosed eccentric4 ,in this is drilled a series of ten holes1 into any of which a pin can be fitted1 so as to unite the arms ,b and ,d1 the pin becoming a hinge or centre of oscillation4 ,the circular ring of the part ,d fits on the part ,d1 ,d of the chuck1 on which it can be secured by the ferrule ,c1 the arm ,d being then in a vertical position4 ,the holes in the eccentric can 7either of them7 be fitted over and secured to the end of the leading screw of the slide-rest4 ,the handle being then placed on the other end of the screw and turned by the hand1 the eccentric will cause the arm ,d to oscillate to and fro through the medium of the connecting rod ,b1 thereby giving to the chuck1 and to the work attached to it1 a similar to and fro movement4 ,the extent of this movement depends upon the length of the lever ,d brought into action4 ,with the pin in the holes #a1 #b1 #c1 the oscillation will be inconsiderable1 but with the pin in either hole numbered #h1 #i1 #aj1 it will be much increased4 ,in the first1 therefore1 a short wave1 ,fig4 #cbj1 will result2 in the second case these will be more like ,fig4 #cbj ,b4 ,this apparatus will completely alter the character of a spiral1 which1 if cut through a hollow cylinder 7as in the case of detached twists7 becomes a zigzag of curved sides curious enough to behold4 ,the apparatus1 it must be understood1 is worked entirely by the handle of the slide-rest1 the lathe-cord being thrown off unless the latter is carried to the overhead instead1 to put in action revolving cutters4 ,the reciprocal action is1 in fact1 a self-acting segment engine4 ,it has been already stated that for the production of spiral work revolving cutters are preferable to fixed ones1 unless1 indeed1 it is required to finish up a perfectly round thread1 when ,figs4 #c and #d of the tools drawn are required4 ,revolving cutters must be placed in the frame of the universal cutter and set to the rake of the thread4 ,drills may be used for the reciprocating movement1 as they make very clean work1 and the rake need not with these be attended to4 ,in face work drills are specially to be used to produce patterns like ,fig4 #cbe1 and others derived from this simple one4 ,an additional apparatus1 represented in ,fig4 #cbc1 is required for the latter process1 to enable the rest to be turned in its socket so as to face the work1 and notwithstanding the alteration of its position still to keep up the gearing of the wheels4 ,a rest socket to be made and mounted as usual is fitted with a stem surmounted by an accurately drilled boss ,a1 through which passes a spindle fitted with the wheel ,c1 to gear with that on the arm carrying the change-wheels1 and which may be changed for one of larger or smaller size4 ,this is for cutting such work as ,fig4 #cbd1 representing1 of course1 only a single spiral1 very open and of itself of no beauty1 but which by intersection of other spirals can be converted into a pattern of great elegance4 ,when it is desired to produce the waved spiral the eccentric is fixed to the rod instead of the wheel ,c1 and the work proceeds the same as when a cylindrical surface is to be worked4 ,in the ,fig4 shown the division plate of this chuck is of course used4 ,illustration3 #a4 ,illustration3 #b4 ,illustration3 #c4 ,illustration3 #d4 ,illustration3 #e4 ,illustration3 #f4 ,it is evident that the variations producible by working intersecting spirals and waved lines are very numerous1 and these may be additionally varied by the combination of eccentric and spiral movements4 ,the following six patterns are re-engraved from ,valicourt's ,hand ,book1 which is almost identical with that of ,bergeron4 ,they were not engraved in time to be inserted under the head of eccentric chuck work4 ,the notation and description annexed is from a manuscript book kindly lent to the writer by an amateur4 ,bed-plate1 #d deg41 must be taken to mean that the work is shifted 7on one of the beds of the chuck7 four of the marked divisions for eccentricity1 counting from the axial line of the mandrel4 ,slide rest1 #d deg41 means that the cutting tool is moved four corresponding divisions in its bed for radius of the circle to be cut2 and so throughout4 #d 991 means four times repeated4 ,the cutting tools1 unless otherwise expressed1 are double angled1 and #be cutting tool1 means #be deg4 of cutting edge4 ,holtzapffel's scale of divisions is ,illustration ,the scale used in ,valicourt is which is that here quoted4 ,illustration ,if bed-plate and slide rest are both equally diminished at each cut1 a shell results1 with the close part internal4 ,if bed-plate is increased and slide rest diminished1 the close part of the shell is external4 ,,specimen ,i4--,tools #be1 #cb1 #cf2 ,click-plate #if or #bhh4 ,bed-plate moved4 ,slide rest moved4 ,circles done4 ,tool4 #c #b #ab99 7#a done #g missed7 #be #f #a #ab99 7#a done #g missed7 #aj #c #dh99 7#a done #a missed7 #cf #c #af #bd99 7#a done #c missed7 #bc #d-a_/b #d99 7#af done #h missed7 #bi-a_/b #b #if99 #be #cc #a #if99 or #cc #e_/h #bhh99 ,,specimen ,,ii4--,tools #bh1 #cf2 ,click-plate #bhh4 ,bed-plate4 ,slide rest4 ,circles done4 ,tool4 #a #a_/b #ab #bh #d #a-a_/b #ab #g-a_/b #b #d 7#h done #d missed7 #cf #ac #c-a_/b #bd #bh #ai-c_/d #c-a_/b #d 7#af done #h missed7 #cf #ai-c_/d #a_/b #d 7in spaces7 #ba-c_/d #a #d 7above last7 ,b #ag-c_/d m #a #d 7below last7 #cf #cj #a_/b #ab 7#bj done #d missed7 #bh #bi-c_/h #a_/b #ab 7 #a #ah 7 7 #a #d 7 #bh-c_/d #a_/b #ab ,ditto4 #bh-a_/h #a_/b #ab #bg-a_/b #a_/b #ab 7#ae done #d missed7 7 #a #d 7 #bf-g_/h #a_/b #ab 7 #a #ah 7 7 #a #d 7 #bf-a_/d #a_/b ,as before #be-e_/h #a_/b ,ditto4 #be #a_/b #ab 7#bj done #d missed7 ,from ,b to here1 border1 if with #if click-plate1 not good-looking2 tool a boring-bit4 #cc-a_/af #g_/h #ab 7#g done #a missed7 #ca-i_/af #ac-afth #ab 7#a #e 7 7#a #a 7 #bi-a_/af #c_/d #ab 7#a #a 7 7#e #a 7 #bg-i_/af #aa-afth #ab 7#a #a 7 7#a #e 7 #be-c_/d #c_/d #ab 7#a #a 7 7#g #a 7 ,,specimen ,,iii4--,click-plate #if4 ,bed-plate4 ,slide rest4 ,circles done4 ,tool4 #a-a_/d #a-a_/h #h #cf #d-a_/d #b-a_/h #bd #e-a_/h #aa-c_/d #bd #ba-a_/b #d-c_/d #if #bg-c_/d #a-a_/b #if #bh ,,specimen ,,iv4 ,the centre of this is a star of six curved rays1 described by fixing the cutter at the centre and turning the mandrel by hand through so many divisions--for convenience so many #dhths of the circumference4 ,these rays are marked by ,b4 7,the segment stop is constructed for this very kind of work1 and is to be used in the present case73-- ,bed-plate4 ,slide rest4 ,arcs done for star4 #e ,b #e #f 7#ab_/dhths of the circle7 #e ,b #e #ab 7#aa_/dhths 7 #e ,b #e #ab 7#aj_/dhths 7 #e ,b #e #ab 7 #h_/dhths 7 #ad-a_/h #e #bd 7#b done1 #b missed7 #ai-c_/d #a_/b #if #bd-a_/d #d #cb #bi-a_/b #b-a_/b #cb 7intersecting7 #cj-a_/b #b #cb ,,specimen ,v4--,catherine wheel2 tool #bh4 ,the ground grailed by concentric circles contiguous to each other4 ,the arcs by fours1 all of same radius4 ,bed-plate4 ,rest4 ,arcs done4 #j #a_/b #c_/d #a-a_/d c4 7for grailing7 ,b #cj #cj #ab 7#af_/dh7 7,repeat at three next divisions47 ,,specimen ,,vi4--,tools #bh1 #cf2 ,click-plate1 #bhh4 ,bed-plate4 ,rest4 ,number4 #a-a_/d #a #h done ,b #ab #ab #ab-g_/dh 7to meet next circle7 #d-c_/h #ag #bd #cj #a_/b #ab #bi-a_/b #a #ab 7,on same radius as the last1 and surrounding it47 #bi #a-a_/b #ab #bh-a_/b #b #ab #bh #b-a_/b #ab #bg-a_/b #c #ab #bg #c-a_/b #ab #bf-a_/b #d #ab #bc-a_/b #a #ab 7#c done1 #ba missed between last1 or if click-plate #if47 #be #a #ab 7between last7 ,although in the matter of beauty the patterns here given are by no means comparable to many others1 especially to some lately published from blocks cut by ,mr4 ,george ,plant1 for the ,english ,mechanic2 they are1 by their comparative simplicity1 well selected to give the learner a good idea of designing and working with the eccentric chuck4 ,it is not1 indeed1 proposed by the writer to multiply patterns1 as mere copying of such is of small interest to those who are really endued with taste and skill2 and the variations producible by combinations of different numbers of divisions of the click-plate and slide rest are of such infinite number1 that printed designs of a score or two would not serve to teach the nature of this work better than the half dozen now before the reader4 ,when a new chuck1 indeed1 is brought out1 it is well to give a few specimens of its work1 to show the possible purchaser its value as a means of ornamentation and the extent of its capabilities2 but when these are understood1 the purchaser had much better design for himself1 instead of becoming a lazy imitator and copying patterns laid down by others4 ,details of designs that are presented in a tabular form remind us sadly 7for we are married7 of the old knit one1 drop two1 purl or some such mysterious and1 to us1 detestable jargon wherewith ladies were1 or are1 wont to worry the ears of mankind4 99 99 99 99 99 ,the chuck of ,professor ,ibbetson1 and the elliptic cutting frame of ,captain ,ash1 are not introduced here1 partly because this work has reached its intended limit1 and partly because the inventors themselves have published separate works entirely devoted to a description of the arrangements and capabilities of their respective chucks4 ,a brief notice is appended of ,plant's geometric chuck1 contributed by the inventor to the pages of the ,english ,mechanic4#bd #bd ,see ,appendix4 99 99 99 99 99 ,the author now concludes his pleasant labours1 the result of which is contained in the preceding pages4 ,these labours have been lightened1 and the work itself benefited1 by several kindly-written remarks received from various readers of the ,english ,mechanic1 while the articles were in course of production in that paper4 ,criticisms and suggestions also came to hand in which no such kindly feelings appeared4 ,these also have1 nevertheless1 had an equal share of attention1 and where they appeared to be of value they have been turned to profit1 and have resulted in various more or less important alterations and additions4 ,the ,lathe and its ,uses1 thus re-arranged and modified1 must now take its chance in the world with other productions of a similar character2 and the writer hopes it may suffice to help those who need such assistance1 and may be well received by others who though able to walk alone may yet cherish a kindly feeling for the friendly walking-stick4 ,,appendix4 ,,professor ,,willis',s ,,tool ,,holder ,,for ,,the ,,slide ,,rest4 ,illustration ,this--described and drawn first in ,holtzapffel's ,mechanical ,manipulation1 to which work the author1 and1 indeed1 most authors of books of the nature of the present1 are indebted for much of their information--is now become very general1 and from its perfect action ought to be universally used in all factories in which the lathe bears a part4 ,it permits the tool to be set at any required angle upon the bed of the slide rest1 and holds it securely when placed in position4 ,it is likewise so constructed as to be easily removed from the table of the rest1 so that other forms of apparatus may be attached if desired4 ,one nut only has to be turned to fix the tool1 this nut turning on a strong central screw1 ,a1 in the figure1 the lower part of which1 as far as the shoulder1 is screwed into the top plate of the rest4 ,this shoulder is directed to be made with flattened sides1 so as to be capable of being unscrewed by the application of a wrench4 ,the actual clamp is a triangular piece of cast or wrought iron1 ,b1 in the centre of which is a hole to allow this piece to go easily over the screw4 ,the hole is hollowed out into a cup-shaped cavity1 into which fits a hemispherical washer1 shown at ,c in the section4 ,the clamping nut1 ,d1 acts upon this washer1 which permits the triangle to take up a position not necessarily quite parallel to the bed of the slide rest1 and thus a tool whose upper and lower surfaces may not be strictly parallel will be securely grasped4 ,the piece called triangular is not precisely of that form1 but of the shape shown in the second figure1 in which ,e1 ,e1 represent two hard steel pins1 slightly projecting--one of these1 ,e1 appearing in the first figure4 ,these pins rest upon the upper surface of the tool4 ,at the third angle the clamping piece is drilled and tapped to receive a screw1 which must work stiffly in this hole4 ,thus when a tool is placed in position1 as shown1 the clamping nut maintains a pressure upon the three points beneath the apices of the triangle4 ,as thus arranged the tool would be stiffly and securely held2 but ,professor ,willis has added a second triangular piece1 nearly similar to the first1 except that it is provided with a boss1 in which a notch or groove is cut1 ,k1 in both figures1 into which the point of the small screw falls4 ,this lower triangle1 which is free to revolve round the central screw1 is also cut away at the line ,l1 ,l1 of the second figure1 so as to form a guide or rest for the side of the tool1 which is thus kept at the same distance from the central screw1 and placed in a moment exactly under the studs or points of the upper plate4 ,a careful inspection of the two drawings will make the precise arrangement clear4 ,in making it1 which is not very difficult1 care must be taken to make the triangle of such size and so to place it1 that no angle can overhang the top plate of the rest1 in whatever position it may be4 ,the hole in the upper triangle or clamp must be tolerably large and slightly conical--the base of the cone upwards1 to allow this piece to take up a bearing1 as described4 ,the hemispherical washer is always in a horizontal position1 and the hole through it may be only of sufficient diameter to allow it to pass freely over the central screw4 ,,munro',s ,,planing ,,machine ,,to ,,be ,,attached ,,to ,,the ,,lathe1 ,,and ,,worked ,,with ,,the ,,foot4 ,in the ,english ,mechanic of ,nov4 #b1 #ahff1 a brief notice was given of the above4 ,the author of the present work having carefully inspected the machine and seen it in operation1 considers it of such great value to the amateur mechanic1 as well as to the professional turner of metal work1 that he has had an engraving of the machine carefully made from a photograph1 and has here appended it to illustrate the description given4 ,it is a lathe for planing1 cutting key-grooves in wheels1 collars1 c41 and cutting racks on the teeth of wheels4 ,the lathe is of the usual construction1 but outside the right hand standard is fixed a vertical spindle1 which is made to rotate by a pair of bevel wheels1 the pinion being fast to the end of the crank shaft1 and in contact with a wheel of double the number of teeth on the vertical spindle4 ,on the top of the latter is a crank-plate1 which will give a stroke of ten inches or less at pleasure4 ,the planing-machine is fixed by two bolts to the lathe-bed1 and a connecting rod is attached to the sliding plate or bed of the planing machine1 the other end of which is made fast to the pin of the crank-plate4 ,the work is clamped by simple means to this sliding bed1 and thus passes to and fro under the tool which1 by self-acting gear1 is made to traverse sideways after each stroke as in the large planing machines4 ,the whole works almost noiselessly and with the greatest ease1 each part being accurately fitted1 and the whole well finished4 ,for such purposes as planing the face of the slide valve and its bed in small engines1 or shaping the guide bars of eccentric and other chucks1 facing the frames of slide-rests1 c41 it is exactly what is needed by the amateur1 rendering the workshop complete for all purposes without the necessity for adding a large and separate planing machine1 which takes up room that cannot always be conveniently spared4 ,with such a lathe as that in the frontispiece1 fitted with one of these planing machines1 there is scarcely a model of machinery that could not be made4 ,any of our readers interested in mechanics would be wise to trip over to ,lambeth and view the machine in operation2 and the writer will guarantee1 not only the most civil and obliging attention from the inventor1 but the greatest pleasure and satisfaction from the working of the machine itself4 ,there is a simple arrangement for key-grooving and slotting1 by attaching the upper slide of the ordinary rest to the crank plate of this machine1 in which case most of the apparatus is removed4 ,illustration3 ,,munro',s ,,machine ,,turning ,,lathe ,,for ,,planing1 ,,etc4 ,,hicks' ,,expanding ,,mandrel4 ,mention of this has been made in the body of the work4 ,it is used for turning rings and washers1 and various sizes of these can be turned upon the same mandrel1 so that a set of three will suffice for all the work likely to be met with even in the largest factories4 ,fig4 #a represents the mandrel complete4 ,f1 ,f is the central part1 with a conical boss1 ,a1 cast upon it1 and the whole turned with great accuracy4 ,four longitudinal dovetailed slots1 seen plainly in ,fig4 #c1 are then planed in the conical part1 and into these are fitted steel wedges1 ,fig4 #b1 ,a and ,b1 and ,b1 ,fig4 #c4 ,c1 ,fig4 #a1 is a hollow conical washer1 which can be advanced over the central part when driven forward by the nut ,d4 ,this washer1 acting on the ends of the sliding wedges1 causes them to move towards the large end of the cone ,a1 and1 from the form of these and of the cone1 any washer or ring will be held tightly when placed outside these wedges1 and will also be mounted concentrically4 ,illustration3 ,,fig4 #a4 ,illustration3 ,,fig4 #b4 ,illustration3 ,,fig4 #c4 ,,turning ,,spheres ,,by ,,means ,,of ,,templates4 ,it is but right to state that the above method has been objected to by a practical workman1 whose business has led him to study the matter closely4 ,he states that it is impossible in this way to effect the desired object4 ,as the writer has not been able to test the working of the apparatus on his own lathe1 he felt inclined1 at first1 to withdraw the whole chapter4 ,the objections offered1 however1 were not1 to his mind1 entirely satisfactory2 and the opinion of other equally scientific and practical men being favourable1 the chapter has been retained4 ,it is possible1 nevertheless1 that there may be a mathematical reason which the writer is not competent to work out1 and the objector being a man of great mechanical knowledge and experience1 his remarks are worthy of consideration4 ,the practical 7not insuperable7 difficulty appears to be the production of a proper tool for this work4 ,,plant',s ,,geometric ,,chuck4 ,this chuck is put in motion by an entirely new method2 none of its parts being attached to the lathe head1 the whole can be put in motion or released in an instant1 and without stopping the lathe4 ,the whole of its work is executed by the continuous motion of the lathe1 so that1 when the chuck is adjusted1 any figure 7no matter how complex7 may be begun and completed without once stopping the lathe4 ,by the different arrangements and adjustments of the chuck and slide rest1 an infinite variety of the most beautiful geometrical figures may be produced2 and some of them of so strange and fortuitous a nature as to bid defiance to any imitation4 ,description of the ,drawings4 ,fig4 #a is a front view1 and ,fig4 #b a view of the back of the chuck4 ,illustration3 ,fig4 #a4 ,illustration3 ,fig4 #b ,illustration3 ,,front ,,elevation4 ,illustration ,illustration ,illustration ,illustration ,illustration ,illustration ,a ,a4 ,the foundation plate screwing on the plate of the mandrel and carrying the whole of the other parts of the chuck4 ,b1 ,c4 ,the two driving wheels giving an independent motion to the chuck4 ,d4 ,angular wheel moving freely on the wheel ,c for the angular adjustment of the figures4 ,e4 ,pinion of any number of teeth fitting on the shaft carrying ,d and ,c4 ,h4 ,large wheel of #abj teeth1 forming the foundation of the second part1 and driven from the pinion ,e by the wheels ,f1 ,g1 and ,t4 ,l4 ,large wheel of #if teeth driven by the pinions and wheels ,u1 ,i1 ,j1 ,k1 and forming the foundation plate of the third part1 ,m1 which carries the nose of the chuck4 ,n1 ,n4 ,self-adjusting radius plates for carrying the various change wheels4 ,o1 ,p4 ,the eccentric slides of the first and second parts4 ,fig4 #b shows the arrangement of the driving wheels and pinions on the back of the chuck4 ,the working of the chuck is as follows3-- ,if the pinion ,e has #bj teeth1 and is geared direct into the wheel ,h1 by means of an intermediate wheel1 it will give six loops inwards if the motions are similar1 and outward loops if the motions are contrary4 ,if the wheel ,h is driven from the pinion ,g it will give #ab1 #bd1 or #dh loops4 ,pinion of #bd teeth will give #e1 #aj1 #bj1 or #dj loops4 ,pinion of #cj teeth will give #d1 #h1 #af1 or #cb loops4 ,pinion of #dj teeth will give #c1 #f1 #ah1 or #cf loops4 ,pinion of #fj teeth will give two loops inwards1 if the motions are similar1 but1 if the motions are contrary1 it will produce an ellipse of any proportion from a straight line to a circle4 ,other combinations will give circulating or overlaying loops4 ,by the different arrangements of wheels and pinions on the plates ,n1 ,n any number of loops can be produced up to #b1eib in the circle4 ,on the opposite page we illustrate some work executed with this chuck by ,mr4 ,plant4 ,fig4 #c is a side elevation of the chuck full size4 ,a1 ,a1 the foundation plate screwing on the nose of the mandrel1 and carrying the whole of the other parts of the chuck4 ,b1 ,c1 the two driving wheels giving an independent motion to the chuck4 ,d1 ,d1 angular wheel moving freely on the wheel ,c1 for the angular adjustment of the figures4 ,e1 ,e1 pinion of any number of teeth fitting on the shaft carrying ,c and ,d4 ,h1 ,h1 large wheel of #abj teeth1 forming foundation of the second part1 and driven from the pinion ,e by the wheels ,f1 ,g1 and ,t4 ,l1 large wheel of #if teeth driven by the wheels and pinions ,i1 ,j1 ,k1 and forming the foundation of the third part1 ,m1 which carries the nose of the chuck4 ,n1 ,n1 self-adjusting radius plates for carrying the various change wheels1 c4 ,o1 ,p1 the eccentric slides of the first and second parts4 ,q1 ,r1 the screws working the eccentric slides4 ,a ,,paper ,,on ,,the ,,principles ,,which ,,govern ,,the ,,formation ,,and ,,application ,,of ,,acute ,,edges1 ,,with ,,special ,,reference ,,to ,,fixed ,,turning-,,tools1 ,,contributed ,,by ,,mr4 ,,dodsworth ,,haydon4 ,the formation of the tools used for turning and planing the metals is a subject of very great importance to the practical engineer1 and it is indeed only when the mathematical principles upon which such tools act are closely followed by the workman that they produce their best effects4--,holtzapffel1 vol4 #b1 p4 #ihc4 ,as the best lathe can do no more than place the work in the most favourable position for the operation of the tool1 and the best tool can only do good work when applied as well as constructed on true principles1 no argument is needed to prove the truth of the statement taken as the text of this paper4 ,but while many of our most eminent practical authorities1 such as ,nasmyth1 ,holtzapffel1 ,babbage1 ,prof4 ,willis1 and others1 have contributed valuable papers on the subject1 no single writer can be said to have embodied all that should be known upon it as a whole4 ,principle may be looked upon as the essence of practice1 and in connection with this particular subject1 the reduction of practice to principle is of comparatively modern growth4 ,this will account for the fragmentary character and occasional difference of opinion1 which marks the treatises of the above-named eminent authorities when compared with each other4 ,as a step towards some more concise and perfect code of principle1 ,i have endeavoured to collate and arrange in consecutive order1 all those laws which govern the action of acute edged turning tools4 ,the object of this paper is not to supply patterns of tools1 as the best form will be no better than the worst unless properly applied2 but to set forth those general principles1 which may enable the workman to distinguish between forms which are accidental and those which are essential1 and thus to make the shape of any tool his servant rather than his guide4 ,whatever the shape or purpose of any acute-edged tool may be1 its action will always depend on the manner in which the extreme edge is applied to the surface acted upon2 and as the same laws govern the action of every acute edge1 whether formed on a razor or a tool for cast iron1 it will assist a clear comprehension of this subject to consider first the action of edges generally1 without reference to any particular tool4 ,the same edge may be made to act in four different ways1 viz43 to cut1 dig1 chatter or scrape4 ,digging and chattering are intermediate stages between cutting and scraping1 and are fatal to good work4 ,thus cutting and scraping remain the two standard principles1 on one of which every tool should be made to act2 and while cutting depends on the penetration of the edge1 scraping results from using an edge so that it cannot penetrate4 ,consequently1 the conditions most favourable to cutting will give the key to both principles of action4 ,every cutting edge is simply a wedge1 keen enough to guide its own path without depending on the grain or other accidental line of separation in the material on which it is employed2 and when such a wedge is forced into any substance1 it will show a constant tendency to penetrate in a line with that face which receives most opposition4 ,the comparative amount of opposition which each face receives1 will be determined either by one having more of its surface in contact with the material than the other as in ,fig4 #b1 or by the material giving way on one side1 as in ,figs4 #a and #c4 ,these last two figures illustrate the action of all paring tools1 to which class cutting lathe tools belong4 ,the dotted lines are added in ,fig4 #b1 to show that the action of the edge is the same1 whether it be formed by one or two bevels4 ,illustration3 ,,illus4 ,no4 #a ,illustration3 ,,illus4 ,no4 #b ,illustration3 ,,illus4 ,no4 #c ,thus in all cases1--except when an edge is applied so that the pressure is equal on both faces1--one face will guide the course of the edge1 and in paring tools this will always be the lower face1 or that next the surface of the work4 ,the first consideration in placing any paring tool must therefore always be that1 the lower face of the edge should lie as nearly as possible in a line with the direction the cut is intended to follow1 so as to place the whole edge in its natural wedge-like position3 for when any edge is compelled to act in a manner contrary to this1 it will assuredly assert its natural tendency by digging and chattering in the direction of its lower face4 ,but when the action of the tool is continuous as in turning1 planing1 or boring1 care must be taken that this face of the edge does not actually rub against that of the work2 and1 to avoid this1 ,nasmyth recommends that the face of the edge should be inclined from the surface of the work at an angle of #c4 ,babbage calls this angle the angle of relief1 because it relieves the friction2 and to show how little variation is admissible in this angle1 ,holtzapffel places its maximum at #f4 ,in cylindrical work the angle of relief is estimated from a tangent to the circumference4 ,thus1 in ,figs4 #d and #g1 the lines ,c1 ,d1 may represent plane surfaces or tangents at pleasure1 and in either case the lower face of each edge is supposed to make an angle of #c with these lines respectively4 ,an examination of the nature of the force required to separate any shaving will show the importance of close attention to the above rule4 ,babbage has pointed out that this process involves two forces1 which1 though simultaneous in their action1 are distinct in the nature of their operation4 ,the first is that necessary to divide the material atom from atom1 and depends on the kind of edge employed4 ,the second force is that required to wedge back the shaving1 so as to make way for the further progress of the edge1 and depends on the manner in which it is applied to the work4 ,now in fibrous and cohesive materials1 the amount of force required to wedge back the shaving is usually greater than that required to effect the initial penetration1 and must always depend on the angle which the upper surface of the edge makes with the face of the work2 while it is obvious that1 whatever the acuteness of the particular edge employed may be1 this angle will be reduced to the minimum obtainable with such an edge1 by keeping its lower face as close as possible to the surface from which the shaving is being wedged off4#be ,a comparison of ,figs4 #d and #e will illustrate this4 ,both edges are supposed to be of the same acuteness1 viz41 #fj1 and in ,fig4 #d1 where the angle of relief is only #c1 the edge of #fj will wedge off the shaving at the smallest available angle1 viz41 #fc1 while the position of the same edge in ,fig4 #e increases this angle to #ij4 #be ,in adopting ,mr4 ,babbage's arguments ,i have varied their form4 ,mr4 ,babbage takes the square of #ij and divides it into three parts1 viz43 ,angle of relief #c ditto edge #fj #ij ditto escape #bg ,the angle of escape is thus estimated from the horizontal line perpendicular to a base line presented by the surface of the work or by a tangent to it4 ,but as the value of this angle depends directly on its relation to the base line1 and has only a complementary relation to the horizontal line1 ,i have thought it better to confine the illustration to the same base as being more directly connected with the wedge-like action of the edge4 ,thus1 as far as regards the force required to bend back the shaving1 the edge of ,fig4 #e might just as well be nearly square1 or #hg1 taking off #c for the angle of relief4 ,indeed1 this less acute edge would work better than one more acute but badly placed1 as in ,fig4 #e2 for the lower face here points too much into the work1 creating the tendency to dig explained above4 ,the same arguments and illustrations apply with equal force to drills and boring tools1 and ,fig4 #e may be looked at as representing one edge of a common drill1 in which the acuteness is obtained by bevelling the under sides only1 leaving the upper face of each edge perpendicular to the surface acted upon4 ,nasmyth has pointed out that the less acute drills of this class are made the better and more smoothly they will cut2 for1 so long as the upper faces are left square to the surface of the work1 increasing the bevel of the lower faces can only increase the tendency to dig and chatter4 ,thus1 whenever acuteness is desired in any cutting edge1 it should always be obtained from the upper face2 and the dotted lines in ,fig4 #d1 suggesting a tool for metal in one case1 and a common wood-turning chisel in the other1 are added to illustrate this1 by showing that the line of the lower face is common to both4 ,no tools afford a better illustration of this principle in boring tools than the ,american twist drills1 which owe the ease and beauty of their action to the spiral flutes being placed so as to give the necessary acuteness from the upper face of each edge1 thus allowing the lower faces to be kept as close as possible to the surface of the work4 ,there is yet one more important practical advantage to be gained from adopting the smallest possible angle of relief4 ,the arrow in ,figs4 #d and #e shows the direction in which the strain of the cut will fall on the edges respectively4 ,it has been shown that the position of ,fig4 #e increases the amount of strain on the edge1 and yet it is apparent that it is less able to bear this increased strain2 for while this falls on ,fig4 #d in its strongest direction--viz41 almost down the length of one face--it falls on ,fig4 #e across the end of the edge1 thus rendering it far more liable to wear and fracture4 ,it is therefore evident that1 in treating plane surfaces1 the cutting action of any acute edge is most favoured when its lower face is placed nearly parallel with the surface acted on2 and in treating cylindrical surfaces1 when the same face occupies the same position with regard to some tangent of the circumference2 or1 in other words1 when the lower face is almost at right angles to some radius of the circle1 as in ,fig4 #d3 and it follows that the tendency to penetrate will be most effectually counteracted when a line at right angles to the surface1 or a radius of the circle1 as in ,fig4 #f1 bisects the edge1 making each face equidistant from the surface which moves across it4 ,thus1 ,fig4 #f represents the scraping position2 and it is obvious that all bow-drills or other tools1 which are said to cut both ways1 must really act on the scraping principle4 ,practical illustrations in support of the universal application of these principles might be multiplied indefinitely2 but two very common operations will suffice to prove that the position of the edge determines the nature of its action4 ,if a penknife be not held with its blade perpendicular to the paper1 when used for scratching out1 it will be sure to hang and chatter2 and the flatter a razor is held to the skin in shaving the more free will the chin be from uncomfortable digs and chatters afterwards4 ,the conditions which next demand notice in the case of turning-tools are those which must be observed to preserve the proper position of the edge under the strain put upon it4 ,these relate to the form of the tool1 and1 in the case of cylindrical work with fixed tools1 to the part of the surface at which the edge of the tool should be applied4 ,drills and boring tools require little notice in this respect1 for1 as the strain is round their axis1 it is only necessary that their shafts should be strong enough not to twist or bend4 ,it must1 however1 be remembered that when common drills are required to be very acute1 the edges should be thrown up a little or hollowed out so as to give the acuteness on the upper face as explained above4#bf #bf ,the common form of drill is rendered far more efficient with wrought iron and materials that require cutting1 by twisting the flat shaft when hot1 so as to reverse the position of each edge after the manner of a screw-auger4 ,the lower faces can then be kept as close as possible to the face of the work while the twist will give a moderate degree of acuteness on the upper face4 ,hand-turning is simply a matter of manual dexterity1 and as any part of the same plane or the same circumference presents the same surface to the edge of the tool1 the correct relation between the edge and the surface can be obtained in many places1 and therefore the particular point at which the edge should be applied is simply a matter of personal convenience1 and may vary with the height of the lathe or that of the workman1 or the shape and nature of the tool employed4 ,the use of the graver affords a good illustration of this2 and it may be remarked1 in connection with this tool1 that none is more simple in construction1 more perfect in principle1 or more convenient in application4 ,when its use is once thoroughly mastered it will do anything from smoothing a pin to roughing out a cylinder four or five inches in diameter4 ,the graver is simply a square bar of steel ground off obliquely at the end2 and by varying the obliquity of this slope the act of grinding one plane face will give two cutting edges of any desired acuteness1 and three heels from which to use these edges at choice4 ,in hand-turning only one edge of the graver is used at a time1 and the lozenge-shaped face is made the lower face common to each edge4 ,now1 when the graver is used for roughing1 the point is generally buried in the clean metal below the central line of the work1 and the lower face is placed against1 and takes the shaving from1 the little shoulder which it forms on the cylinder4 ,when the graver is used for smoothing1 the lower face is placed nearly flat against the face of the work1 and the edge is generally made to bite on1 or a little above1 the central line4 ,but for very light finishing cuts the graver may be used from the heel at the bottom of its lozenge face1 and in this position its point is over the top of the work1 bringing the biting part of the edge still more above the central line4 ,thus1 the only three points to consider in placing the tool in hand-turning are--first1 that the lower face of the edge should occupy the proper position with regard to the surface2 secondly1 that the handle of the tool should come up conveniently to the hands of the operator2 and thirdly1 that while these two conditions are observed1 the heel of the tool should be able to take a firm bearing on the rest4 ,the best rule for hand-turning is1 therefore1 to apply the tool to the work1 with these ends in view before fixing the rest1 and then to bring that up to the necessary position4 ,when the heel of any hand tool has a firm bearing on the rest1 and the edge is applied in the wedge-like position1 the preservation of this during the progress of the work depends on delicacy of touch rather than muscular power4 ,but when the edges are applied out of their natural line1 it puzzles a strong wrist to keep them to their cut at all without digging into the work4 ,this affords the best practical illustration of the necessity of careful attention to the position of slide-rest tools1 which are deprived of all power of accommodation to the sense of touch1 and which therefore require accurate adjustment in the first instance4 ,for the motion of the tool is now confined to that of the rest1 and as this moves in horizontal planes1 the edge of the tool must be applied to the work on that parallel plane which passes through the lathe centres4 ,the reason for this rule will be at once apparent1 if the edge be not placed on this central line in facing up a plate--for then it will lose its cut before reaching the centre1 leaving a core untouched4 ,now although it would require an exaggerated error in the position of the edge to lose cut altogether in turning a cylinder1 yet this example proves that1 unless the edge be applied exactly on the central line the relative position between it and the surface of the work1 on which the cutting action depends1 will imperceptibly change with the reduction of the work2 and supposing this to vary much in diameter1 the same tool may cut beautifully on one part and badly on another4 ,fig4 #d1 which illustrates the cutting action of the edge1 has been purposely placed on a part of the circle where a slide-rest tool could only act for a very short time1 in order to draw attention to the difference between those conditions which govern the cutting action1 and those which depend on the motion of the rest from which the tool is used4 ,it is obvious that if ,fig4 #d were moved inwards on a horizontal line the edge would pass over the smaller circle without touching it4 ,the illustration is of course exaggerated1 but it proves that ,fig4 #g is the only position in which the tool will cut over varying diameters without some change in the relative positions of its lower face and that of the work4 ,hence the usual instructions to apply the edge about the centre of the work4 ,but ,babbage has observed1 that however good this direction may be as far it goes1 it is insufficient and liable to mislead when given alone4 ,it is impossible to do away with elasticity when the tool is supported at some lateral distance from the line of strain1 as in the slide rest or planing machine2 and unless this elasticity is counteracted by the position of the tool1 it may upset the best position of the edge4 ,to meet this1 ,babbage gives the following rule--,first1 consider whereabouts the tool itself will bend under strain on its edge1 when fixed in the rest2 and then take care that this part of the tool1 which ,babbage calls the centre of flexure1--is placed above a line joining the centre of the work and the edge of the tool4 ,fig4 #g will explain the reasons for this rule and the consequences of neglecting it when there is much strain put on the edge4 ,let ,e1 ,i1 ,f1 be the line joining the centre of the work and the edge of the tool4 ,then if ,g above this line be the centre of flexure1 when the tool bends its edge must follow some part of the arc1 ,h1 ,i1 ,j1 from ,g as a centre1 and will be thrown out of the work4 ,but if ,k below the line1 ,e1 ,i1 ,f1 be the centre of flexure1 then1 under the same circumstances1 the edge will follow some part of the arc ,l1 ,i1 ,m1 from ,k as a centre1 and must dig into the work4 ,it is important to recognise this principle1 because while it shows that every tool in which the top of the edge stands above the shaft must be liable to the evils resulting from elasticity1 it shows also that even cranked tools may fail to obviate the danger1 unless care is taken to place the weakest point in the shaft above the central line4 ,babbage remarks1 that although it is not always possible to strengthen any part of a tool1 it is always possible and sometimes desirable to make some particular point weaker than the rest1 by cutting away a little where the weak point should be4 ,fig4 #i shows that the crank principle may be applied in another form1 and although the crank is upwards in this case1 the same object is attained by making ,p the weakest point1 and placing it above the central line1 ,n1 ,o4 ,this form1 however1 is only used for light finishing cuts2 for any unnecessary length of crank evidently adds elasticity1 and ,holtzapffel observes that1 in adopting the crank form tools the principle must not be carried to excess1 as it must be remembered we can never expunge elasticity from our materials1 whether viewed in relation to the machine1 the tool1 or the work4 ,the crank1 therefore1 should only be just sufficient to give the edge the right direction if the tool should spring2 and ,holtzapffel remarks1 that as a tool will generally bend somewhere in the central line of its shaft1 it is sufficient if the top of the edge is kept on or just below this line1 as in ,fig4 #h4 ,referring again to ,fig4 #g1 and looking at the line ,c1 ,d1 as a plane surface1 and ,i1 ,f1 as a line perpendicular to that surface1 the same arguments and illustrations apply to the form of a tool in the planing machine4 ,the point at which the tool is now applied ceases to be of moment4 ,having considered the conditions necessary to insure the best cutting action of acute edges and the preservation of that action during the progress of the work1 it remains to treat of the edges most suitable to particular materials1 the method of giving them any desired angle1 and the manner of applying slide-rest tools so as to obtain the best work with the least expenditure of force and time4 ,willis observes that different metals and qualities of the same metal require to be treated with edges differing in their degree of acuteness1 and all the standard authorities concur in giving the following code as near enough for all practical purposes4 ,the modification of these angles is ruled by the general principle that fibrous and cohesive materials require more acute edges than crystalline and granular substances1 as will be apparent in the following code3-- ,wrought iron and steel #fj ,cast do4 do4 #gj ,roughing brass #hj ,finishing do4 #ij ,thus the edges available for the metals commonly treated in the lathe find their maximum at #ij and minimum at #fj4 ,the maximum requires no explanation1 as when any edge is larger it ceases to be an acute edge4 ,with regard to the minimum of #fj1 ,babbage has pointed out that this is dependent not only on the strength necessary to resist the strain of the cut1 but further and chiefly on the temper which must be preserved in the edge2 and if this be less than #fj the mass of metal composing the extreme edge will be too small to carry off the heat generated by the cut1 consequently the extreme edge would soon lose temper and become useless4 ,but these different edges are formed in very different ways according to the purpose for which the tool is intended2 and this will be best understood by comparing the action of a hand-turning chisel with that of a pointed slide-rest tool4 ,in the first case the edge is applied at an oblique tangent to the surface1 and removes the shaving by passing under its whole width1 much after the manner in which an apple is pared1 or a ribbon unwound from a stick1 when the lower edge of one turn just overlaps the top edge of the turn below it1 and so on4 ,in this case the shaving can be cleanly detached by one straight edge4 ,but the position and motion of the slide-rest tool being perpendicular to the axis of the work1 its action becomes that of uncoiling rather than paring2 and as a cord or wire wound round a stick touches the face of the stick in one direction1 and the coil next to itself in another1 so in this case the width and thickness of the shaving lie in opposite directions1 as illustrated by the dark band in ,fig4 #aj4 ,consequently1 unless the shaving be cut simultaneously in these two directions--viz41 from the face of the work on one side1 and from the matter under removal on the other1 it is obvious that it must be torn from the work in one direction1 thus increasing the labour and spoiling the appearance of the work if the tearing should be from its face4 ,now1 in practice1 at any rate in the rough cut1 it is usual to take the width of the shaving from the superfluous matter2 and if the tool be placed1 as in ,fig4 #aa1 it can only cut on one edge2 thus the edge of the shaving will be torn from the face of the work1 while the point of the tool will trace a fine thread in its progress along it1 leaving the face with a rough unfinished appearance4 ,but if the edges be formed so that they can be placed as in ,figs4 #aj and #ab1 then both can cut simultaneously1 and the screw-like trace of the point may be obliterated4 ,this method of using the tool will leave the work with a good face from the first rough cut1 leaving very little for the finishing cut to do2 in addition to which the labour will be reduced to a minimum1 thereby permitting a much heavier cut from the same amount of force4 ,in turning any plane surface the corner of the edge should be sufficiently relieved from it to avoid the danger of catching2 but1 in turning cylindrical surfaces1 if the tool be carefully made and placed1 the slope of the upper surface will carry the corner out of cut4 ,experiment must decide the exact adjustment2 but the great aim should be to keep the face of the tool next the work as nearly parallel with it as possible1 because it is only that face which leaves any trace of the tool's action on the face of the work--the action of the other edge being lost with the shaving4 ,illustration3 ,,illus4 ,no4 #d ,thus tools may be broadly divided into two classes--viz41 single-edged and double-edged--remembering always that this distinction refers to the manner in which they should act1 and not to the number of edges which it may be convenient to form on the same tool4 ,in single-edged tools1 whether there be one or many edges1 each edge acts independently in removing its own shaving1 and may therefore be formed separately4 ,in this case a longitudinal section1 showing the angle of the point1 will give a true idea of that of the cutting edge4 ,but1 in the case of double-edged tools1 as the two edges should co-operate in the removal of the same shaving1 they must also be formed so that1 while each lower face can occupy its proper position with regard to that surface of the work opposed to it1 both edges shall possess the same degree of acuteness4 ,in this case the two edges are formed by three planes--viz41 two side faces and one upper surface common to both2 and the angle of the point is now not only not that of the cutting edges1 but has not even any fixed relation to them1 for the cutting edges may vary some #be or more on the very same longitudinal section of the point4 ,prof4 ,willis has pointed out that in these tools the angles of the cutting edges depend on the section and plan angles of the point conjointly 7,fig4 #h is a section view2 ,figs4 #aj1 #aa and #ab are plan views74 ,from this it follows that cutting edges of exactly the same angle may be obtained by a great variety of combinations in the plan and section angles2 and in note ,a1 ,u1 of ,holtzapffel's work1 vol4 ii4 p4 #iid1 ,prof4 ,willis has given a table1 showing some of the different combinations by which cutting edges of certain angles may be produced with accuracy and simplicity4 ,the following short table is arranged from this source and though much abbreviated will be found sufficient for all ordinary purposes4 ,illustration3 ------------------------------------- ,,plan ,,angle ,,with ,,section ,,angles --------------------- #adj #gi4e #fi #eh #abj #gh4e #fg #ee #ajj #gg #fc4e #di4e #ij #gf #fa #de #gj #gb4e #ec4e #bi --------------------- ,,will ,,give ------- ,,cutting ,,edges --------------------- #hj #gj #fj ----------------------------------- ,the graver will again serve to illustrate the use of this table2 for although only one edge is employed at the same time in hand turning1 it belongs properly to the double edged class4 ,this will be very apparent if a graver is held point upwards side by side with a point tool1 and the dotted lines are added in ,fig4 #h1 to make the similarity of form more evident4 ,now ,holtzapffel has said of the graver when employed for its original purpose of engraving1 that no instrument works more perfectly1 pointing out that1 while both the edges are engaged in cutting the same shaving1 both the lower faces of the edges are respectively inclined at the smallest possible angle from the sides of the ,v-shaped groove4 ,fig4 #aj has already been used to illustrate the best position of the slide-rest tool1 and if the illustration be turned round until the letters ,q1 ,r1 read horizontally1 and this line be taken to represent a flat surface with the graver acting upon it1 it will be seen that the shaving is removed in exactly the same manner in both cases2 the only difference being that the section of the shaving is triangular in one case and rectangular in the other4 ,but so far as the tool is concerned the action is identical in each case1 thus proving that every point tool may be so made and placed as to merit ,holtzapffel's eulogium on the graver1 and that this simple tool is in fact the type of all double-edged tools4 ,the graver being made from a square bar has of course a plan angle of #ij1 and using it to illustrate the table1 we will suppose that it is desired to give it two cutting edges of #fj each4 ,referring to #ij under the heading of plan angle1 #de will be found on this line in the column over cutting edge #fj2 denoting that the section angle of the point1 i4e41 the slope at which the graver is ground1 must be #de to give the desired edges4 ,in the same way1 if the section angle were #fa the cutting edges would be #gj4 ,but taking the plan angle of #abj1 the table shows that this would produce the same cutting edges of #fj with the larger section of #ee2 and from this we have the important rule that1 in obtaining cutting edges of any given degree of acuteness the larger the plan angle is made1 the larger also may be the section angle4 ,thus pointed tools though constructed on the principle of the graver are an improvement on it in its simple form2 for by making both plan and section angles as wide as possible1 it is obvious that the strength and durability of the point will be much increased4 ,it is1 therefore1 always better to give slide-rest tools a large plan angle1 as in ,fig4 #ab2 and plan #abj1 with section #ee1 will be found a very useful and durable tool for surfacing purposes with wrought iron4 ,when there are rectangular corners to cut in and out of1 of course the plan angle cannot be more than #ij1 and then it is well to sacrifice a little of the acuteness1 as the section of #de makes the point rather too weak4 ,it is also worthy of remark as a mathematical fact1 that unless the plan angle exceed #fj1 it is impossible to obtain two cutting edges of that degree of acuteness2 and in any case1 such a plan angle would be radically bad1 because it could not be used on the double-edged principle without undercutting the shaving4 ,it is somewhat remarkable1 in connection with this point1 that while ,holtzapffel1 vol4 ii4 p4 #ecf1 recommends prismatic cutters1 he should add a footnote which indirectly but most conclusively corroborates ,prof4 ,willis' condemnation of that particular form1 by admitting that the proper degree of acuteness cannot be given to both edges4 ,as the practical result of a circular edge is to cut in two opposite directions1--the edge passing gradually from one to the other1--so round-nosed tools belong properly to the double-edged class1 and are open to great objections unless carefully formed on this principle4 ,illustration3 ,,illus4 ,no4 #e ,this is illustrated in ,fig4 #ac1 representing an oblique section of a round bar2 and supposing the section to be made at an angle of #de1 it is obvious that the highest part of the edge at ,s will be exactly of this angle1 while the lower point at ,t will be #ace1 and the side points at ,u and ,v will be #ij each4 ,thus1 between the point ,s and the points ,u and ,v on each side respectively1 the edge will gradually pass through a range of #de1 consequently no two adjacent points on the same side will be of the same angle1 and the highest point ,s may be too acute to stand while the lowest1 ,u or ,v1 is too blunt to cut4 ,whenever1 therefore1 it is intended to round the nose of the tool1 it should be first formed as a double-edged point tool1 with a section angle agreeing as nearly as practicable with the intended degree of acuteness in the edge1 so as to secure the highest points from being too weak1 and the table given above will show what plan angle must be used1 in combination with this section1 to secure any part from being too blunt4 ,thus1 supposing a circular edge of about #fj is desired1 the section of #eh approaches this most nearly1 and if the plan of #adj1 which1 with this section1 gives two straight cutting edges of #fj1 be adopted1 there can only be a variation of #b in different parts of the edge4 ,but it will be observed that this combination admits of very little rounding2 and although less acute edges1 being obtainable with a smaller plan-angle1 admit of rather more rounding1 it may be taken as a general rule that when any tool is much rounded on the nose1 so as to present a large segment of a circle1 different parts of the edge must vary considerably in acuteness4 ,although ,professor ,willis objects to rounding the nose of a tool at all on account of the necessary variation in the character of the edge and some other reasons1 ,i am disposed to think that when the tool is carefully formed on the principles given above1 it is very advantageous to round off the point slightly for taking heavy cuts2 and ,i have found this form a favourite one in such workshops as ,woolwich ,arsenal and ,portsmouth ,dockyard4 ,but care must be taken to place the nose of the tool towards the width of the shaving 7presuming that this is taken from the matter to be removed1 as it usually is17 for unless the edge is straight1 and almost parallel with the face of the work as it leaves it1 the face would be marked with a series of concave grooves of greater or less width1 according to the feed given to the tool2 and even when this is very slow1 if the curved part of the edge were placed towards the face of the work it would present the appearance of corrugated iron1 when examined under a magnifying lens4 ,willis further advances against the round nose that1 as the shaving removed by it must be of a curvilinear section1 it will oppose more force in rolling itself off the edge1 than a flat shaving4 ,this would be quite true if a flat shaving could be rolled up on itself like a piece of tape or ribbon2 but ,i think the professor has overlooked the fact that when two cutting edges have one common upper face the shaving must be bent laterally as well as in its length2 and ,i am disposed to think1 from practical experiment1 that there is very little difference on the point of the force required1 and that when a point of large plan angle is just rounded off it stands better and cuts sweeter than when the point is not so rounded4 ,but this only applies to heavy cuts1 and for ordinary surfacing work nothing can act more perfectly than a point tool of wide plan-angle placed as described above4 ,if a double-edged tool1 with edges of #fj1 be thus used in turning wrought iron or steel1 and be well lubricated with clean water during the progress of the work1 its face may be left with a burnished brilliancy that a touch of the finest emery would spoil4 ,but1 as the scheme of this paper is confined to the principles which determine the action of edges1 and the rules by which those edges may be formed with certainty1 it will be well to conclude these remarks with a few hints as to the construction of ordinary slide-rest tools4 ,bearing in mind that all double-edged tools belong to the graver class1 it is well to form the side faces carefully in the first instance1 and then never to alter these1 but to keep the tool in order by grinding in the upper surface only1 just as the graver is treated4 ,nasmyth's cone gauge1 illustrated in ,holtzapffel1 vol4 ii41 p4 #ecd1 and also in ,baker's ,mechanism1 p4 #bcf1 affords a ready means of forming the side faces with accuracy4 ,but the range and convenience of this gauge is much increased by dispensing with every part of the arrangement1 except the cone itself4 ,this can be made of any piece of stout metal bar turned truly1 with the slide-rest set at an angle of #c1 and the base should be broad enough to stand steady by itself when squared off truly in the lathe1 as in ,fig4 #ad4 ,two marks can then be made upon it3 one as at ,w1 showing the exact height of the lathe-centre when the cone stands on the bed of the lathe1 and another as at ,x1 showing the height of the centre when the cone is placed on any given part of the slide-rest4 ,thus1 in whatever direction the tool is to be used1 its adjustment can be accurately made in the first instance on the slide-rest itself1 and again tested after the tool is clamped down4 ,it is too common a practice in setting slide-rest tools to wedge up one end or the other1 with regard only to the application of the edge on the central line4 ,but this generally sacrifices the position of the lower faces1 which is essential1 to a consideration which has been shown to be only secondary4 ,the best plan is to keep several strips1 varying from #a_/cb to #a_/b inch in thickness1 but all about as long and wide as the shaft of the tool4 ,these can be made of bar iron for the thicker strips1 and sheet iron or tin for the thinner ones2 and by using any two or three of these together1 the tool can be packed up parallel to the bed of the slide-rest4 ,the adjustment of the edge can thus be made with the greatest ease and certainty without altering the relative position of the lower faces4 ,it may be well to remark that in using the cone gauge1 it is the lower faces of each edge which are to be tried against it1 and not the front line of the point1 as the inclination of this rule will vary slightly with variations in the plan-angle of the tool1 although the slope of the faces remains the same4 ,but the section angle is always to be estimated from the front line1 whatever its slope may be4 ,illustration3 ,no4 #f ,when the principles which this paper has endeavoured to embody are once thoroughly understood1 no handy workmen need ever be at a loss to form and apply his edges with the best effect under any shape the circumstances may require4 ,the first point to be observed is the manner in which the work should be attacked--that is to say1 whether the removal of the shaving or scraping requires the use of a single or double-edged tool4 ,the next point is the position of the lower face or faces of the edges1 so that they may be applied in the required direction1 and in the position explained above4 ,this involves the nature of the treatment best suited to the material1 both as regards the kind of edge employed and the principle on which it should be applied--viz41 cutting or scraping4 ,in double-edged tools the position of the two lower faces determines that of the point1 which is simply an accident resulting from the meeting of the cutting edges2 but which1 when so determined1 affords a guide for the slope of the upper face4 ,this must be so ground that it gives each edge the same degree of acuteness4 ,thus1 in ,fig4 #ae1 the point of the tool being at ,a1 the slope must be made in the direction ,a1 ,b2 while1 in ,fig4 #af1 the point being at ,c1 the slope of the upper face must be in the direction ,c1 ,d4 ,the writer is fully aware that those who expect to find a rule of thumb in this paper1 will be miserably disappointed4 ,but while he is conscious that the principles of which he has treated admit of a much fuller and yet more concise definition1 he would remind the novice that there is no royal road to learning1 and that where practice of hand is wanting it can only be supplied by greater knowledge of principle4 ,his object will therefore be fulfilled if this supplementary paper can supply any explanation or illustration of principle that may add to the practical utility of a work so exhaustive of its subject as the ,lathe and its ,uses4 ,,detached-,,cutter ,,holders4 ,where amateurs experience inconvenience in making their tools from the want of a forge1 the use of detached cutters in a tool holder will be found of the greatest advantage for outside work4 ,even in plain turning there must always be some special forms for cutting into odd corners and deep grooves2 but with a good tool holder and a grindstone1 which is an indispensable piece of furniture in every metal turner's shop1 the cumbrous array of slide-rest tools may be reduced to a few special forms and a very small box of cutters4 ,these also possess another great advantage2 for the spirit of the old adage quoted by ,holtzapffel-- ,he that would a good edge win ,must forge thick and grind thin1 may be carried out far more conveniently than in the case of whole tools which are generally filed into shape before tempering1 and when worn down must go to the fire again and have the process repeated4 ,but the detached cutter admits of being tempered evenly throughout its whole length and ground up afterwards as long as it lasts1 without going to the forge again to the deterioration of the steel4 ,the patterns of tool-holders are innumerable1 but very few are good for general service1 because most of them are arranged so that the natural sides of the cutter are used for the face or faces of the edge4 ,thus either the plan angle of the point is limited to the angles presented by the transverse section of the cutter employed1 or else the section angle is fixed by the position in which the cutter is clamped4 ,holtzapffel's arrangement is open to the first objection1 ,babbage's to the second4 ,to obviate this inconvenience1 ,prof4 ,willis arranged a holder which clamps the cutter at an angle of #ee from the horizontal line4 ,thus no side can be used either for the lower or upper face of the edge1 but any faces can be ground upon it2 and the plan and section angle of the edge may be varied at pleasure within the whole range available for metal turning4 ,prof4 ,willis's holder for the cutter is almost a facsimile of his admirable tool-holder for the slide-rest1 than which none is more convenient or can act more perfectly4 ,but the arrangement is a little complicated for a cutter holder1 and must be very carefully made with the knowledge of certain laws1 if it is to insure a perfect grip of the cutter4 ,it is also designed for the use of sound wire cutters which require filing flat on one side4 ,illustration ,adopting ,willis's inclination for the cutter ,i have found that all its advantages may be secured with a simpler form of holder and common square for steel for the cutter4 ,the holder is simply the modification of an old pattern to suit the inclination of #ee1 and the sketch needs little explanation beyond saying that the nick in the solid part should be rather less than a square angle1 and made perfectly true all the way down1 or1 if anything1 rather hollowed in the middle1 so as to insure the greatest amount of pressure at the top and bottom1 as otherwise the cutter might not sit quite true and firm4 ,the angle at the end of the strap against which the cutter bears should be rather more than square1 both to allow for any want of exact truth in the squaring of the cutter and to avoid the wedging action which would be set up on tightening the screw if this angle were less than square1 as this could of course create a risk of splitting the strap4 ,the end of the screw and the cup in which it fits should be round1 as this allows of a little play and insures a truer grip in the strap than a pointed screw working into a conical hole4 ,a perspective sketch of a detached cutter is added1 with dotted lines to show how exactly the arrangement of the faces can be accommodated to the positions which have been shown to be the best in solid tools for the slide-rest4 ,d4 ,,haydon4 ,,new ,,form ,,of ,,rose ,,engine ,,by ,e4 ,,taylor4 ,seeing that the ,editor of the above ,articles has illustrated and described ,holtzapffel and ,co4's ,rose ,cutter and two methods of executing rose cutting1 the latter being the ordinary rose engine1 ,i am induced to send you a description of a method that ,i have adopted whereby ,i can with considerable despatch execute this description of turning4 ,i will first preface my description by saying some thirty years ago ,i purchased ,ibbetson's ,book on eccentric turning1 and ,i was so much taken with it and the illustrations1 that ,i determined to make myself in accordance with his description and engravings an eccentric chuck2 and although ,i was a long time about it1 being at the time much otherwise engaged1 ,i succeeded beyond my expectations1 and was enabled to do some very fine work with it2 and ,i have never regretted the time ,i spent over the chuck1 as ,i became familiar with metal turning and screw cutting flying in the lathe1 which latter ,i was surprised to find how easily ,i could execute4 ,however1 ,i was much disappointed in the usefulness of the chuck 7,holtzapffel's eccentric cutter1 which ,i purchased is far more useful71 and also with the tediousness of using it 7fancy stopping the lathe to alter the chuck #cfj times or #ahj times to cut a row of circles either distinct or overlaying each other71 and there was also a certain vibration occasioned in using the chuck which ,i also disliked4 ,i therefore determined to cut up some rosettes and convert my headstock into a rose engine1 to effect which object ,i got ,holtzapffel and ,co4 to return up with a new steel collar and make my mandrel traversing4 ,i cut myself a rosette both ways with #af waves1 and ,i was much pleased with the variety of work ,i could perform with this one1 but the rosette took me a long time to make1 and disheartened me from cutting up a variety4 ,it1 however1 occurred to me that if ,i added an extra mandrel by the side of and attached to my headstock1 and on which extra mandrel1 if ,i had an eccentric chuck connected with a rod to the wall of my room1 ,i could get my headstock to oscillate1 and by connecting and multiplying wheels cause as many waves on each revolution of my principal mandrel ,i pleased2 this after much time and patience ,i succeeded in doing1 and worked it with the hand motion often adopted for rose work4 ,after between two and three years1 ,i put the extra mandrel over my principal mandrel instead of by the side as before1 to enable me to dispense with the hand motion and to work the upper mandrel with the slow motion on my lathe wheel1 and which ,i found a very great improvement1 and ,i now give the details of the plan ,i have adopted for the benefit of your numerous readers4 ,the drawings are to a two-inch scale1 or one sixth of their full size4 ,fig4 #djj is a side view of my headstock 7part in section7 with the upper mandrel1 ,a1 added1 showing the connection by an intermediate spindle1 ,b1 with the large cog wheel1 ,c1 on my lower mandrel1 ,d1 and other additions4 ,the back centre1 ,e1 of my headstock is connected with the back screw1 ,f1 and drawn out or pushed in with it1 and is fixed by the set screw1 ,g4 ,when drawn out the steel screw1 ,h1 at the end of the mandrel1 ,d1 removes to receive the screw guides which are then fastened by it1 and the piece1 ,i1 with segments of a thread to match the guides1 is slid up by a wedge to the guides and then fastened by the screw ,j1 ,i1 can also fix some roses cut on the side1 and other apparatus with this screw ,h4#bg #bg ,it is not a good plan to make the point1 ,e1 movable4 ,it would be better to slip the guides or rosettes over it3 and generally to arrange this part as usual with a traversing mandrel1 ,p1 ,h4 ,the large cog wheel1 ,c1 is screwed up with the screw1 ,k1 to the mandrel pulley1 ,l4 ,on the front of the pulley is the division plate as usual4 ,the intermediate adjustable spindle1 ,b1 is carried in a frame shown separately by ,fig4 #dje2 it is allowed to rise or fall as may be required for the wheel1 ,m1 to gear with the great wheel1 ,c2 provision being also made for an intermediate wheel1 ,n1 7see ,fig4 #djc7 to connect the wheel1 ,o1 with the wheel1 ,p1 on the upper mandrel when required4 ,the eccentric chuck is fixed on screw ,q of the upper mandrel4 ,fig4 #dja is a plan of the mould for the back cast-iron upright1 fixed to the headstock with screws at the foot1 showing the circular grooves #a1 #b and #c1 necessary for the spindles for the connecting wheels2 the centre hole1 #d1 is for the gun-metal collar1 or the upper mandrel4 ,fig4 #djb1 is a plan of the mould for the front cast-iron upright2 the centre holes #a and #b are for the collars of the mandrels4 ,no4 #b is made to just fit over the steel collar of the lower mandrel1 and is fixed to the headstock by a brass rose and three screws2 it is also fixed at the foot with two screws to the headstock4 ,these two castings1 #dja and #djb1 are bolted together with two bolts and nuts through the holes #e and #f1 as shown in ,fig4 #djj4 ,fig4 #djc1 is a back view of the additions1 showing the cog wheels and their connections1 also the brass bearings for the lower mandrel required when allowed to traverse4 ,this was a solid piece of brass with a hole bored out and ground to fit the mandrel4 ,it was then drilled the whole depth in two places1 for two steel steady pins1 b1 c1 made to fit quite tight1 and at both ends for bolts and nuts1 a1 d1 afterwards sawn in two with the circular saw1 and when put together and two holes drilled through the thickness for fixing it was put in its place1 adjusted1 and re-ground on4 ,the holes for fixing were very carefully continued through the cast iron upright1 and the whole was finally fixed with two screw bolts and nuts4 ,fig4 #djd1 is a front view1 showing the eccentric chuck1 ,r1 on the upper mandrel1 the slide of which when used is connected with the bracket in the wall1 ,fig4 #djf1 causing the whole apparatus to oscillate in proportion to the eccentricity of the chuck on its centres one of which is marked at ,s4 ,the chuck has a circular movement for laying the waves in any position with one another1 but which also is effected by another plan to be presently described4 ,the whole poppet with its fittings is hung on centres similar to the rose engine described in this work4 ,the top part of the bed ,t removes1 and the two screws1 one shown at ,v1 are taken out to allow the oscillation4 ,the large cog wheel has #aib teeth4 ,illustration3 ,,fig4 #djj4 ,illustration3 ,,fig4 #dja4 ,illustration3 ,,fig4 #djb4 ,illustration3 ,,fig4 #djc4 ,illustration3 ,,fig4 #djd4 ,illustration3 ,,fig4 #dje4 ,illustration3 ,,fig4 #djf4 ,the whole of the additions to my headstock were all of my own fitting up4 ,the brass cog wheels were bored out and ground to fit an arbor made on purpose1 exactly corresponding in diameter with the ends of the spindles so that they might fit indiscriminately on either spindle4 ,when turned up1 the teeth were cut with a circular cutter1 which ,i made just of the exact shape and thickness required for the space between the teeth4 ,the cutter was turned of steel2 then wrapped in leather and enclosed in sheet iron4 ,it was then put in the fire1 made red hot1 and left for the fire to go out1 the next day being soft1 it was cut with sharp chisels into a circular file and hardened1 and with it in the cutter frame the teeth of the wheels were cut4 ,the central boss of each wheel has a notch cut across the face to receive a pin in the arbor and in the spindles1 which prevents the wheels from turning round on the latter when screwed up4 ,this rose engine works beautifully smooth and easy1 and ornamentation can be done with it with greater rapidity than with the ordinary engine1 by arranging the connecting wheels so that the upper mandrel makes so many waves and one-half1 one-third1 one-fourth1 one-fifth1 one-sixth1 or any other part of a wave1 on each revolution of the lower mandrel1 because then it requires certain revolutions of the lower mandrel before the tool comes into the same cut again--say1 for instance1 it makes #d-e_/f waves on each revolution1 then it takes #bi revolutions of the upper mandrel to complete the pattern1 whereby certain patterns are completed without stopping the lathe1 which is an advantage that the rose engine proper does not possess4 ,another great advantage is1 that the waves can be either flat1 sharp1 or intermediate1 as required for large or small work1 by altering the eccentric chuck on the upper mandrel4 ,i give a few specimens1 not for the beauty of design1 but to illustrate the working of the engine4 ,the centre of ,fig4 #djg is performed by having a wheel of #hj teeth on the upper mandrel1 connected with one of #be teeth on the intermediate spindle1 which has another of #ej teeth connected with the large wheel of #aib teeth on the lower mandrel2 thus1 #hj_/be #ej_/aij #a-a_/e producing on each revolution of the lower mandrel one wave1 and one-fifth of another wave1 requiring six revolutions to complete the pattern4 ,the remainder of the pattern is completed by wheels1 #af1 #ej2 #dh1 #aib making #ab-a_/b waves on each revolution of the lower mandrel1 requiring #be waves to complete the pattern1 and laying the waves over each other1 and with the slide rest movement of the tool4 ,fig4 #djh is produced by wheels #cb1 #dh2 #bd1 #aib making #ab waves4 ,the centre is done by altering the eccentric chuck each time4 ,it was purposely executed askew1 by the tool not being placed in the centre1 to show the importance of doing so for some patterns4 ,the rim was executed with the same wheels1 and with the slide rest movement of the tool1 and1 after two cuts1 the chuck turned half round1 to lay the waves over each other for the other two cuts4 ,fig4 #dji is all executed with wheels #if1 #cj2 #be1 #aib making two waves and two-fifths of another wave1 requiring #ab waves to complete the pattern4 ,the two centre rims produced by placing the tool above the centre4 ,the outside by four movements of the slide rest tool1 illustrating how soon patterns are produced1 and when well cut up look very pretty4 ,fig4 #daj is executed with wheels #hj1 #ej2 #be1 #aib making four waves and four-fifths of another wave1 requiring #bd waves to complete the pattern4 ,the centre is all done without stopping2 the outside rim by altering the eccentric chuck four times1 to make each successive wave flatter4 ,fig4 #daa is an illustration of the upper mandrel1 making #e-a_/c revolutions to one of the lathe1 requiring #af revolutions to complete the pattern and slide-rest movement4 ,fig4 #dab4 ,the outer pattern of this figure is produced by the upper mandrel making #ab-d_/e revolutions to one of the lathe1 requiring #fd revolutions to complete the pattern4 ,the centre is a rosette of #e waves1 slide-rest movement and placed across each other4 ,illustration3 ,,fig4 #djg4 ,illustration3 ,,fig4 #djh4 ,illustration3 ,,fig4 #dji4 ,illustration3 ,,fig4 #daj4 ,illustration3 ,,fig4 #daa4 ,illustration3 ,,fig4 #dab4 ,fig4 #dac4 ,the whole of this pattern produced by the upper mandrel making #c-c_/e revolutions to one of the lathe1 producing #ah waves across each other with slide-rest movement for the middle rim4 ,fig4 #dad illustrates a rosette of nine waves with slide-rest movement1 and #c divisions of the circular movement of the eccentric chuck for each successive line1 producing the waved appearance4 ,fig4 #dae illustrates a rosette of #bd waves with the slide-rest movement4 ,fig4 #daf4 ,another illustration of a rosette of #bd waves1 rather more sharp than in ,fig4 #dae1 with slide-rest movement and #i divisions of the circular movement of the eccentric chuck1 giving it a pleasing circular waved appearance4 ,fig4 #dag4 ,also another illustration as the last1 but with the waves much sharper1 the slide-rest movement and only two divisions of the circular movement of the eccentric chuck producing the star-like pattern4 ,fig4 #dah illustrates also a rosette of #bd waves1 with the eccentric chuck turned half-way round with each movement of the slide-rest1 producing the pattern so often seen on the back of watches1 only being on wood it is on a larger scale4 ,illustration3 ,,fig4 #dac4 ,illustration3 ,,fig4 #dad4 ,illustration3 ,,fig4 #dae4 ,illustration3 ,,fig4 #daf4 ,illustration3 ,,fig4 #dag4 ,illustration3 ,,fig4 #dah4 ,the above illustrations are sufficient to give a distinct idea of the working of my engine1 and the last four show how easily patterns are multiplied and varied4 ,the whole of the preceding patterns were executed by the wood being chucked in the lathe in the usual ordinary way without any particular chuck whatever1 but in combination with any of the ornamental chucks innumerable patterns can be produced4 ,fig4 #dai is one illustration with an eccentric chuck on the lathe mandrel4 ,illustration3 ,,fig4 #dai4 ,that my description may be complete ,i will now give drawings of my eccentric chuck for the upper mandrel4 ,it requires to be constructed differently to the ordinary eccentric chuck1 as the circular movement requires to be always central1 and only the slide carrying the pin to receive the rod must move eccentrically4 ,illustration3 ,,fig4 #dbj1 also #dbb4 ,illustration3 ,,fig4 #dba1 also #dbc4 ,figs4 #dbj and #dba1 are full-size drawings of my eccentric chuck on my upper mandrel1 used for producing the foregoing specimens4 ,in this case ,i have preferred a wood foundation1 as not being so likely to run off as metal1 on reversing the motion which is sometimes necessary on account of idle wheels for the connections4 ,i used a piece of well-seasoned ,spanish mahogany1 taking care that the grain of the wood was at right angles with the length of the screw of the mandrel4 ,a piece of brass is screwed at the back to prevent the screw cutting into the wood4 ,fig4 #dbj is a section1 and ,fig4 #dba a front view of the chuck1 and ,i think all sufficiently clear4 ,i will just say the long fine threaded screw ,i cut up with the stocks and dies in the lathe1 using steel wire of the necessary size4 ,this ,i manage easily1 and keep the wire straight by allowing it to expand in length4 ,i chuck the steel wire concentrically1 and removing the centre from the back poppet1 substitute a brass centre with a hole the size of the steel wire1 which is allowed about a quarter of an inch entry4 ,i then turn down a little below the depth of the intended screw thread for about half an inch in length next the back centre1 to allow the dies to come back to be tightened up1 and which must only be done at the commencement and not on the return motion of the dies4 ,the collar on the screw is a piece of brass with a hole of a size to drive on the wire tight1 and is then pinned on and turned up true1 and finished with the division marks4 ,,oval ,,turning ,,and ,,rose ,,cutting ,,with ,,templates ,,with ,,my ,,apparatus4 ,figs4 #dbb and #dbc are full size drawings of my chuck1 with circular movement for templates for my upper mandrel1 which has also a wood foundation4 ,fig4 #dbb is a section1 and ,fig4 #dbc is a front view4 ,by removing the eccentric chuck from the upper mandrel1 and substituting the chuck ,figs4 #dbb and #dbc with a circular movement1 to receive templates of any pattern1 ,,ovals with the oval template can be turned and also with any irregular templates1 patterns cut and placed in any direction over each other1 by causing the templates to work against a rubber or roller as most desirable1 with an india-rubber spring to keep them together4 ,the following illustrations will give some faint idea of productions from templates4 ,fig4 #dbd1 is the production of an oval template and slide-rest movement1 both mandrels making equal revolutions4 ,fig4 #dbe the same as ,fig4 #dbd1 with the patterns laid across each other by turning the circular movement of the chuck #ab divisions4 ,fig4 #dbf1 is from an oval template1 which is caused to make two revolutions to one of the lathe mandrel producing #d waves and undulations and with the slide-rest movement4 ,it will be perceived in this case the form of the oval is superseded by another pattern1 and shows how great a change in the form of patterns from templates my rose engine with change wheels effects4 ,fig4 #dbg1 is also from an oval template1 caused to make #e revolutions to one of the lathe1 and with the circular movement of the chuck and the slide-rest movement1 and in this case the form of the oval is also superseded4 ,indeed1 none but those who have made the matter their study would have the slightest idea that this pattern could be produced from an oval template4 ,fig4 #dbh1 is also from an oval template1 it is finer than #dbg1 but is done in the same way by the template making nine revolutions to one of the lathe mandrel4 ,illustration3 ,,fig4 #dbd4 ,illustration3 ,,fig4 #dbe4 ,illustration3 ,,fig4 #dbf4 ,illustration3 ,,fig4 #dbg4 ,illustration3 ,,fig4 #dbh4 ,the above are a few specimens of the oval1 but sufficient to draw attention to the great variety of patterns that can be executed1 and these illustrations have only been made to go even revolutions with the lathe mandrel2 but of course can be made to go1 as already described1 uneven revolutions1 laying the lines over each other for variety of patterns4 ,fig4 #dbi1 is a curiosity from a square template with equal revolutions1 the outside rim and inside pattern by the circular movement of the template chuck4 ,fig4 #dcj1 is also from a square template made to go two revolutions to one of the lathe and with the slide-rest movement4 ,the centre pattern with the circular movement of the chuck4 ,fig4 #dca1 is the production of a heart-shape template1 and with the slide-rest movement and the patterns laid across each other1 the mandrels making equal revolutions4 ,fig4 #dcb1 is also from a heart-shape template made to go two revolutions to one of the lathe and the slide-rest movement4 ,but in this case the slide-rest tool is used on the opposite side of the lathe bed to the roller against the template1 and therefore reversing the pattern1 that is1 the projections of the pattern are the hollows of the template1 and vice versa4 ,i have introduced it to show how easily patterns are multiplied in the most simple way4 ,it will also be observed that the form of the template is superseded4 ,fig4 #dcc1 is another illustration of the heart-shape template1 but made to go five revolutions to one of the lathe1 with the circular movement of the template chuck1 and the slide-rest movement1 and in which case the form of the template is entirely superseded4 ,fig4 #dcd1 is also a similar illustration to #dcc1 only finer2 they can be of course as fine as desired4 ,the above are1 ,i think1 sufficient to illustrate the productions from templates1 some very pretty patterns can be executed4 ,my object is more particularly to exhibit the use and extended application of my rose engine1 and it will be perceived the last two are not the most easily working templates4 ,the variety of patterns that can be executed with this engine are so innumerable that one may say they are infinite4 ,well may you in your article quote what ,bergeron says of the rose engine1 that it is necessary to know thoroughly the particular one in use4 ,i also make use of the cogwheel on my mandrel1 by connecting it by a spindle and the change wheels with a large compound slide rest1 for executing spiral turning1 and also with my slide rest for ornamental turning1 for small spiral work2 and with a chuck with a circular movement ,i can cut several spirals to one stem4 ,illustration3 ,,fig4 #dbi4 ,illustration3 ,,fig4 #dcj4 ,illustration3 ,,fig4 #dca4 ,illustration3 ,,fig4 #dcb4 ,illustration3 ,,fig4 #dcc4 ,illustration3 ,,fig4 #dcd4 ,in concluding my description ,i will say the specimens given have all been cut on a plain surface1 and this has been unavoidable on account of printing1 but for the information of those unacquainted with the rose engine1 the very great advantages of which over the eccentric and geometrical chucks are that the work can be executed on concave or convex surfaces4 ,i make use of mine for ornamenting the roofs of temples and ,chinese pagodas1 either domed1 curvilinear1 or circular pointed1 by representing them covered with shingles1 c4 ,the geometric chuck will produce very beautiful intricate lacework1 but not more so than my apparatus1 as they both are on the same principle of change wheels1 and can both produce equally fine work2 but with my apparatus the work is always concentric with the mandrel1 and therefore much more pleasing to execute4 ,,elias ,,taylor4 ,hartford ,villa1 ,patcham1 near ,brighton1 ,sussex4 ,,judd ,,glass1 ,,phoenix ,,printing ,,works1 ,,doctors' ,,commons1 ,e4,c4 ,,advertisements4 ,,established ,a4,d4 #ahbb4 ,illustration ,,james ,,lewis4 #da1 ,,great ,,queen ,,street1 ,,lincoln',s ,,inn ,,fields1 7,late ,,lewis ,,son1 of ,wych ,street1 ,strand71 ,engineer1 ,machinist1 ,lathe and ,tool ,maker1 and ,modeller of ,new ,inventions1 for ,english or ,foreign ,patents1 from ,drawings or ,specifications1 in ,brass1 ,iron1 or ,wood4 ,also ,manufacturer of ,steam ,engines and ,boilers for driving ,amateur ,lathes1 ,pleasure ,boats1 c41 the ,boilers fitted with ,messrs4 ,field's ,patent ,circulating ,tubes2 whereby a great saving of ,fuel and space is effected2 or can be fitted for ,gas4 ,model ,steam ,engines and ,boilers kept in ,stock1 and the different parts may be had for making the same4 ,estimates given for all kinds of ,work4 ,country ,orders punctually attended to4 ,,joseph ,,lewis',s4 ,,patent ,,combined ,,drill1 ,,circular ,,saw1 ,,and ,,fret ,,machine4 ,illustration ,patterns and designs for ,picture ,frames1 ,brackets1 ,reading ,desks1 etc41 from #c;d4 each1 or #bs4 #f;d4 per dozen assorted4 ,to fix on ,lathe #c #j #j ,ladies' ,machine #d #j #j ,ditto ditto #e #j #j ,gentlemen's ditto #e #j #j ,ditto1 with drill #f #aj #j ,gentlemen's ,machines with ,circular ,saw #h #j #j ,ditto1 ditto1 ditto1 with the improved ,saw-shifting ,apparatus complete #i #aj #j ,best ,saws from #d-a_/b;d4 per doz41 #ds4 per gross4 ,ornamental ,drills from #as4 each4 #ea1 ,,high ,,street1 ,,bloomsbury4 ,illustration ,,joseph ,,lewis1 ,,engineer1 ,,machinist1 ,,lathe ,,and ,,tool ,,maker1 ,,and ,,modeller ,,of ,,new ,,inventions4 ,manufacturer of every description of ,plain and ,ornamental ,lathes1 ,chucks1 ,slide ,rests1 ,tools1 ,drills1 over-hand motions1 ,division ,plates1 c4 ,lathes #h #j #j1 #aj #j #j1 #ab #j #j1 #ad #j #j1 #af #j #j1 #be #j #j4 ,amateurs supplied with ,castings1 ,forgings of ,lathe ,engines1 c41 and assisted in making the same4 ,illustration ,,joseph ,,lewis',s ,apparatus for cutting ,screws of all nitches1 self-acting1 made and fitted to any ,lathe4 #ea1 ,high ,st41 ,bloomsbury1 ,london4 ,,james ,,munro1 7,from ,messrs4 ,,holtzapffel ,co47 ,,engineer1 ,,machinist1 ,,lathe ,,and ,,tool ,,maker1 ,,manufacturer ,,of ,,all ,,kinds ,,of ,,lathe ,,apparatus ,,for ,,plain ,,or ,,ornamental ,,turning1 ,,die ,,stocks1 ,,taps1 ,,screw ,,tools1 ,,oval ,,and ,,eccentric ,,chucks1 ,,cutting ,,frames1 c4 #d1 ,,gibson ,,street1 ,,waterloo ,,road1 ,,london1 ,s4 ,illustration3 ,,machine ,,turning ,,lathe ,,for ,,planing1 ,,etc41 ,,etc4 ,,invented ,,by ,j4 ,,munro4 ,illustration3 ,,hand ,,planing ,,machine4 99 99 99 99 99 ,,james ,,munro respectfully invites the attention of ,amateurs and ,manufacturers to the excellence of workmanship and construction of the various descriptions of ,lathe ,machines and apparatus produced in his manufactory1 which has secured the approval of numerous patrons4 99 99 99 99 99 ,specimens may be seen at the ,museum of ,patents1 ,south ,kensington4 ,,the ,,english ,,mechanic ,and ,mirror of ,science1 ,,is ,,an ,,illustrated ,,record ,,of ,engineering1 ,building1 ,new ,inventions1 ,photography1 ,chemistry1 ,electricity1 c41 c4 99 99 99 99 99 ,weekly1 price #b;d42 post #c;d4 ,monthly parts1 #i;d42 post #aa;d4 ,quarterly ,subscription1 post-free1 #cs4 #c;d4 ,vol4 ,,vi4 now ready1 #gs42 post-free1 #hs4 99 99 99 99 99 7,from the ,weekly ,times47 ,technical education forms just now a topic of more than ordinary importance1 and1 as far as we can see1 ',the ,english ,mechanic' fills a large space in providing technical food for the workmen of ,great ,britain4 ,there is scarcely a subject in the scientific or mechanical world that is not practically described in this excellent journal1 and all the technicalities explained with a particularity quite remarkable4 ,here the workman in all departments of trade will find something to interest him1 and many things explained by which he will be able to make the best use of his knowledge4 ,the editor is always anxious to satisfy the cravings of his readers by giving every information possible to those who may require it4 ,the trouble taken in this department is apparent on reference to the ',letters to the ,editor' and ',replies to ,queries1' both of which form original1 very important1 and useful features of the magazine4 ,under the head1 also1 of ',our ,subscribers' ,exchange ,club1' a means is opened for persons to exchange one article for another on mutually advantageous terms1 and for this accommodation no charge is made4 ,for instance1 one correspondent says he has a silver watch which he would exchange for ',the ,lives of ,eminent ,men2' another wants 'a cottage piano' for 'a three-horse power horizontal engine2' and a third has 'a hand sewing machine1' which he would give for 'a parallel sliding vice4' ,the illustrations of ',the ,english ,mechanic' are worthy of all praise2 they are drawn with an exactness which is so necessary1 and so much appreciated by workmen1 and are also well printed4 ,throughout the whole publication there is a visible1 a practical1 and technical knowledge of a high order--a kind of knowledge that is highly prized by all mechanics and men of science4 99 99 99 99 99 7,from the ,morning ,advertiser7 ',the ,english ,mechanic4'--,illustrated with appropriate engravings1 this valuable periodical is replete with information of the most valuable kind in every department of engineering1 and in all applications of the principles of physical science4 ,its contents are exceedingly varied1 and embrace1 in a form adapted for immediate and convenient reference1 a well-digested account of any noteworthy progress made in the mechanical or chemical arts1 at home or abroad4 ,for all purposes of the inventor1 we do not know a periodical more likely to give him that assistance which he could expect to derive from recent means and appliances4 99 99 99 99 99 7,from the ,observer47 ',the ,english ,mechanic and ,mirror of ,science' is a publication which contains much that is new and instructive in various branches of science4 99 99 99 99 99 ,now ready1 price #i;d42 post free1 #aj;d4 ,,the ,,engineer',s ,,slide ,,rule1 and its ,,applications4 ,a complete investigation of the principles upon which the ,slide ,rule is constructed1 together with the method of its application to all purposes of the ,practical ,mechanic4 99 99 99 99 99 ,published by the ,proprietor1 ,,geo4 ,,maddick1 #b #c1 ,shoe ,lane1 ,fleet ,street1 ,and to be had of all ,booksellers4 ,,established ,a4,d4 #ahaj4 ,illustration ,w4 ,j4 ,,evans1 ,,engine1 ,,lathe ,,and ,,tool ,,maker1 ,,and ,,general ,,machinist1 #ajd1 ,,wardour ,,street1 ,,soho1 ,,london4 ,,turning1 ,,planing1 ,,screw ,,and ,,wheel ,,cutting ,,to ,,drawings ,,and ,,models4 ,amateurs' turning ,lathes of every description for ,plain1 ,eccentric1 ,oval and ,ornamental turning1 also the various tools and apparatus the ,mechanical ,arts4 ,instruction given to ,amateurs in ,plain and ,ornamental ,turning in all its ,branches4 ,contractor to ,her ,majesty's ,war ,department4 99 99 99 99 99 ,,lathes1 ,,and ,,every ,,description ,,of ,,tool ,,for ,,amateur ,,turners4 ,lathes complete1 #g #es41 #i1 #aa1 #af #afs4 ,,chucks ,,all ,,kinds ,,of ,,apparatus ,,fitted ,,to ,,lathes4 ,engineers' ,files and ,tools of every description4 ,,american ,,twist ,,drills1 ,and ,self-centering ,chucks for holding all sized ,drills4 ,,american ,,scroll ,,chucks ,,of ,,all ,,sizes ,can be readily fitted to any ,lathe4 99 99 99 99 99 ,,joseph ,,buck1 #abd1 ,,newgate ,,street1 ,e4,c41 ,and #afd1 ,,waterloo ,,road1 ,s41 ,,london4 ,w4 ,,blackett1 ,,hope ,,iron ,,works1 ,,southwark ,,bridge ,,road1 ,,london1 ,,manufacturer ,,of ,engineers1 ,millwrights1 ,iron ,ship ,builders1 and ,boiler ,makers' ,tools4 ,illustration3 ,,planing ,,machine4 ,illustration3 ,,screw ,,cutting ,,foot ,,lathe4 ,illustration3 ,,sliding ,,and ,,screw ,,cutting ,,lathe4 ,the ,machines usually on hand consist of large and small ,boring and ,drilling ,machines2 ,universal ,shaping1 ,planing1 ,slotting1 ,bolt-screwing1 ,single and ,double ended ,punching and ,shearing ,machines2 a variety of ,self-acting1 ,sliding1 and ,screw-cutting ,lathes1 ,hand ,lathes1 ,foot ,lathes1 ,compound ,slide ,rests1 ,planed ,iron ,lathe ,beds1 ,ratchet ,drill ,braces1 ,screwing ,tackle1 ,screw ,jacks1 and other ,tools1 such as are usually required in ,engineering ,establishments4 ,tools not in stock made to order4 ,,advertisements4 ,by ,her ,majesty's ,royal ,letters ,patent4 ,illustration ,,cunningham ,,and ,,co41 #dhj1 ,,new ,,oxford ,,street1 ,,london1 ,w4,c41 ,,ornamental ,,wood ,,and ,,metal ,,cutting ,,machines1 ,,and ,,drilling ,,apparatus4 ,,adapted ,,for ,,ladies' ,,use4 ,illustration ,useful to the following ,trades--,organ ,builders--,cabinet ,makers--,pattern ,makers--,chair ,makers--,gun ,case ,makers--,marqueterie ,makers--,toy ,maker--,jewel ,case ,makers--,carvers--,cutlers--,leather ,cutters--,engravers--,jewellers--,chand elier ,makers--,electrotypers--,stereotypers-- c4 ,will cut ,brass a ,quarter inch thick with ease4 ,the working of the ,machine is very simple1 and can be learnt by an amateur in five minutes4 ,patentees of the ,,cam ,,roller ,,buffing1 ,,for ,preventing ,noise in ,machinery4 ,illustration ,see ,,engineer1 ,jan4 #bdth1 #ahfh4 ,w4 ,j4 ,,cunningham ,,and ,,co4 ,beg to call the attention of the ,public to their newly-invented ,ornamental ,wood and ,metal ,cutting ,machine4 ,its extreme simplicity of construction precluding the possibility of speedily getting out of order1 having no springs1 and its peculiar adaptability to all kinds of fret-work render it at once an acquisition and an indispensability where accuracy1 expedition1 and high finish are required4 ,the working is exceedingly easy1 requiring no more exertion than an ordinary ,sewing ,machine for ladies' use1 and making as little noise4 ,its great utility1 combined with neatness of construction1 fits it not only for the workshop1 but the drawing-room of the amateur4 ,the saw takes the place of a pencil in the hands of the operator1 enabling him to produce the most elaborate artistic designs in wood-work4 ,box or other hard texture woods1 #a inch thick1 are as readily sawn through as the finest veneer2 metallic plates of #a_/h inch thick are also speedily pierced4 ,magnificent specimens executed by this machine1 which have been universally admired for their extreme delicacy and perfection1 and acknowledged to be unrivalled1 may be seen at the inventor's address4 ,the length of stroke of the saw can be varied to the work in hand4 ,a simple mechanical contrivance is attached for blowing the sawdust from the saw whilst working1 also a ,circular ,saw4 ,an equally valuable invention is ,w4 ,j4 ,c4 ,co4's ,,patented ,,drilling ,,apparatus which is with the greatest advantage combined with the ,sawing ,machine1 enhancing and enlarging its range of usefulness1 or it may be adapted to a lathe1 or as a distinct machine4 ,its great advantages over the ordinary lathe for drilling purposes must be apparent when by the addition of this apparatus to a #e inch centre lathe the operator is enabled to drill in the centre of three or more feet1 and the drill being vertical and worked by leverage1 greater accuracy and facility is ensured4 ,for ornamental purposes it surpasses all hitherto contrived methods1 not being limited to one centre around which to describe curves1 angles1 circles1 or any other mathematical figure1 the operator is at perfect liberty to describe every conceivable device the fancy can dictate4 ,advantages and ,capabilities of this ,machine4 ,this ,machine can be adapted to any ,lathe1 see page #aca4 ,this ,machine has a ,circular ,saw4 ,this ,machine has a ,vertical ,saw4 ,this ,machine has a true ,parallel ,motion4 ,this ,machine has no ,springs whatever4 ,this ,machine has a ,bead and ,moulding ,apparatus4 ,this ,machine has a ,planing ,apparatus4 ,this ,machine has a ,drilling and ,grooving ,apparatus4 ,this ,machine has a ,kinography that will engrave hundreds of different patterns on wood or metal4 ,this ,machine will cut ,spirals and ,ovals4 ,this ,machine has a ,pentagraph1 for reducing1 enlarging1 and cutting on the face of wood any drawing from paper or fret-work4 ,circulars and all particulars on application4 ,every kind of ,materials1 viz41 ,saws1 ,fret ,patterns1 ,fancy ,wood ,drills1 ,cutters1 c41 kept in stock4 ,,manufacturers ,,of ,,turning ,,lathes4 ,,and ,,all ,,kinds ,,of ,,mechanical ,,tools4 ,,moseley ,,and ,,simpson1 ,,late ,,john ,,moseley ,,son1 #ag #ah1 ,,king ,,st4 ,,and #bg1 ,,bedford ,,st41 ,,covent ,,garden1 ,,london1 ,w4,c4 ,,established #agcj4 ,illustration ,illustration ,,lathe ,,and ,,tool ,,manufacturers1 c41 c4 ,,price ,,list ,,of ,,lathes4 ,turning ,lathe1 ,iron ,frame and ,bed planed true1 ,wood ,tool ,board1 ,iron ,cone ,mandrel1 ,cylinder poppet head1 ,rest and two ,tees1 ,turned ,grooved ,wheel ,crank1 ,treadle complete with #c ,chucks3-- ,no4 #a4 #c-a_/b inch centre1 and #b foot #f inch ,bed #aj #aj #j #b4 #d-a_/b #c ,bed #ab #ab #j #c4 #e #d #ae #ae #j #d4 #e #d with ,brass ,pulley and ,slide ,rest #ba #j #j #e4 #f inch centre and #d feet ,bed with ,slide ,rest complete #be #j #j #f4 #g inch centre1 #f feet ,bed1 self-acting1 and ,screw ,cutting leading ,screw1 and #bb ,change ,wheels #dj #j #j ,for ,lathes of other descriptions1 ,estimates are furnished on ,application4 ,,turning ,,tools4 s4 d4 ,chisels for ,soft ,wood1 the set of #f handled #h #j ,gouges #i #j ,tools for hardwood and metal1 handled and ready for use1 per dozen #ae #j ,drills handled #j #g ,arm ,rests ,handled #b #f ,callipers from #a #j ,turner's ,squares from #f #j ,all ,kinds of ,chucks1 ,cutters1 c41 made to order4 ,transcriber's ,note3 #a4 ,page #ch1 ,bunhill-row1 ,covent-garden and ,charing-cross seems to be an old-fashioned way of writing4 #b4 ,italics are shown as text1 bold is shown as text4 #c4 ,carat characters are shown as ,x4 #d4 ,this table of contents has been created by the transcriber to aid the reader4 #e4 ,footnote #bj1 ,page #ahc3 ,footnote marker is missing4 #f4 ,page #bch3 starting the #crd table1 there is a fraction #cc-a_/ad4 ,this has been changed this to #cc-a_/af1 as it seems to be a mistake4 #g4 ,spelling errors such as guidepiece1 sawgates1 swiveljoint1 tongueing and whiteing have been retained as they are in the original4 #h4 ,discrepancies with #c_/d-;inch and #a_/d;in4 have been retained as in the original4 #i4 ,inconsistencies with images3 a4 ,page #bb3 ,fig #ca;,d is incorrect in the book as ,e4 ,changed to #ca;,d and the fig4 no4 on the image has been removed4 b4 ,pages #cf #ch3 numbers #ec-ef are repeated4 c4 ,page #gd3 ,it seems the reference 7,fig4 #abf7 should be ,fig4#aaf4 d4 ,page #hi3 ,there is no ,fig4 #acg or a reference to it4 e4 ,page #ii3 ,the number #i on the image is back to front4 ,there does not seem to be a ,fig4 #adh1 although it is referred to 7page #ih74 f4 ,page #ih3 ,fig4 #adh is incorrectly numbered on the image as #adc4 g4 ,page #ajj3 ,there is a #bnd reference to ,fig4 #adi1 which it seems has to be an illustration of a pattern1 but there is no #bnd ,fig4 #adi4 ,it seems the ,fig4 nos4 mentioned in the reference should be #aej to #aec4 h4 ,page #ajd3 ,the illustration is incorrectly numbered as #aec 7should be #aef74 i4 ,page #ajg3 ,the number #i on the image is back to front4 j4 ,page #aaa3 ,the number #f on the images is back to front4 k4 ,page #aab3 ,fig4 #aff incorrectly numbered as #afe4 l4 ,page #ada3 ,there is no ,fig4 #bjd4 7assumed to be the top image above ,fig4#bje74 m4 ,page #aei_/afj3 ,number repeat for ,fig4 #bbi4 n4 ,page #afj3 ,there is no ,fig4 #bcj4 ,possibly the #bnd no4 #bbi4 o4 ,page #agh-ahd3 ,numbers #bdf-bee are number repeats4 p4 ,page #ahe_/f3 ,there is no ,fig4 #beg1 but no reference to it either1 so it is assumed this was an omission by the author4 q4 ,page #ahi3 ,there is no ,fig4 #bfa1 although it is referred to on page #ahi4 ,the reference has been changed to ,fig4 #bfb1 which it pertains to4 r4 ,page #bja3 ,fig4 #bhd is out of sequence1 it appears on page #bji4 s4 ,page #bjg3 ,it seems the reference should be to ,fig4 #bij1 not #bif which has no ,l in the figure4 t4 ,page #bca3 ,fig1 #cai is referred to1 but there is no ,fig4 #cai4 ,presumably the first figure on ,page #bcc4 u4 ,page #bcf3 ,illustration top un-numbered1 presumably #d4 v4 ,page #bgh3 ,figs1 #dbb_/c is referred to1 but there are no ,figs4 #dbb_/c4 ,based on extensive research1 comparing two different copies of a matching edition1 and correlation of illustrations with the text1 it appears that the inconsistencies in numbering within the book make it seem that something is missing4 ,the images are in fact ,figs4 #dbj and #dba4