,,electric ,,gas ,,lighting ,,how ,,to ,,install ,,electric ,,gas ,,igniting ,,apparatus ,,including ,,the ,,jump ,,spark ,,and ,,multiple ,,systems ,,for ,,use ,,in ,,houses1 ,,churches1 ,,theatres1 ,,halls1 ,,schools1 ,,stores ,,or ,,any ,,large ,,buildings ,,also ,,the ,,care ,,and ,,selection ,,of ,,suitable ,,batteries4 ,,wiring ,,and ,,repairs ,by ,h4 ,s4 ,,norrie 7,,norman ,h4 ,,schneider7 7,author of 8,induction ,coils and ,coil ,making07 ,,first ,,edition ,,new ,,york ,,spon ,,chamberlain #ab ,,cortlandt ,,street ,,london ,e4 ,f4 ,n4 ,,spon1 ,,limited1 #abe ,,strand #aija ,entered according to ,act of ,congress in the year #aija ,by ,,spon ,,chamberlain in the office of the ,librarian of ,congress1 ,washington1 ,d4 ,c4 ,,the ,,burr ,,printing ,,house1 ,,frankfort ,,and ,,jacob ,,sts41 ,n4,y4 ,,preface ,the ,electric ,light possesses the great advantage over gas1 in that it can be turned on or lighted from a distance4 ,the customary means of igniting gas with a match or taper is both dangerous and often inconvenient4 ,the inventive genius of modern times has evolved a means of lighting gas by electricity which is both reliable and easy of application4 ,it requires no very complicated devices1 nor does it necessitate a deep knowledge of electrical matters for its installation4 ,the object of the following pages is to enable any one possessing ordinary mechanical ability to construct much of the apparatus used1 or at least to successfully erect it and keep it in operation4 ,we beg to thank the following firms for the use of illustrations3 ,edwards ,co41 ,mott ,haven1 ,new ,york2 ,a4 ,l4 ,bogart1 ,new ,york2 ,wm4 ,roche1 ,new ,york2 ,the ,electric ,gas-,lighting ,co41 ,boston1 ,mass41 and ,the ,manhattan ,electrical ,supply ,co41 ,new ,york4 ,,contents4 ,,chapter ,i4 ,,introductory ,,remarks4 ,introduction2 means of producing sparks2 ,induction--,simple induction coils--,ruhmkorff ,coils #a ,,chapter ,,ii4 ,,multiple ,,gas ,,lighting4 ,application of induction coils to gas-lighting--,forms of burners used--,pendant ,burners--,ratchet ,burners--,stem ,burners--,welsbach ,burners--,burners for ,acetylene ,gas--,burners for ,gasolene--,automatic ,burners #g ,,chapter ,,iii4 ,,connections ,,and ,,wiring4 ,how to connect up apparatus--,wiring a house--,locating breaks or short-circuits--,wiring in finished houses--,general remarks #bf ,,chapter ,,iv4 ,,primary ,,coils ,,and ,,safety ,,devices4 ,how to make a simple induction coil--,automatic ,cut-outs--,the ,syracuse ,cut-out--,boston ,cut-out--,edwards' ,cut-out #df ,,chapter ,v4 ,,lighting ,,of ,,large ,,buildings4 ,series or ,jump ,spark ,system--,burners used--,how to ,wire--,edwards' ,condenser ,system--,switches for series lighting--,how to make a #b-;inch spark1 ,ruhmkorff ,coil #ee ,,chapter ,,vi4 ,,how ,,to ,,select ,,batteries ,,for ,,gas ,,lighting4 ,electrical ,rules--,electromotive force--,amperes--,resistance--,selecting a battery--,arrangement of battery--,series--,multiple--,how to get high voltage or large current--,the ,leclanche ,cell--,the ,samson ,cell--,the ,dry ,cell and how to make one--,the ,edison-,lalande ,cell--,the ,fuller ,cell--,care and maintenance of batteries #gh ,,list ,,of ,,illustrations4 ,,frontispiece--,,complete ,,wiring ,,plan ,,for ,a ,,house4 #a ,,diagram ,,of ,,simple ,,circuit #b #b ,,diagram ,,of ,,simple ,,circuit ,,with ,,spiral #b #c ,,diagram ,,of ,,simple ,,circuit ,,with ,,spiral ,,and ,,galvanometer #b #d ,,diagram ,,of ,,circuit ,,with ,,iron ,,core #d #e ,,diagram ,,of ,,ruhmkorff ,,coil #d #f ,,elevation ,,of ,,ruhmkorff ,,coil #f #g ,,pendant ,,burner #g #h ,,burner ,,circuit #h #i ,,plain ,,burner #aj #aj ,,ratchet ,,burner #aa #aa ,,stiff-,,pull ,,pendant #ab #ab ,,stem ,,burner #ad #ac ,,argand ,,burner #ae #ad ,,welsbach ,,burner #af #ae ,,acetylene ,,burner #ag #af ,,push ,,button #ai #ag ,,bartholdi ,,burner #ba #ah ,,boston ,,automatic #bb #ai ,,concealed ,,automatic #bd #bj ,,diagram ,,wiring ,,one 8,,automatic0 ,,from ,,two ,,pushes #bg #ba ,,diagram ,,wiring ,,one 8,,automatic0 ,,and ,,two ,,pendant ,,burners #bh #bb ,,simple ,,switch ,,connections #cc #bc ,,details ,,of ,,automatic ,,connections #ce #bd ,,details ,,of ,,cellar ,,automatic ,,circuits #ce #be ,,nut ,,wrench #dj #bf ,,automatic ,,operated ,,by ,,door-,,trip #dd #bg ,,primary ,,coil #df #bh ,,syracuse ,,cut-,,out #ej #bi ,,boston ,,cut-,,out #ea #cj ,,details ,,cut-,,out ,,rod--,,normal #eb #ca ,,details ,,cut-,,out ,,rod--,,operating #ec #cb ,,bulb ,,cut-,,out #ed #cc ,,jump ,,spark ,,burner #ef #cd ,,welsbach ,,burner ,,for ,,series ,,lighting #ef #ce ,,pillar ,,burner #ef #cf ,,circuit ,,for ,,jump ,,spark ,,gas ,,lighting #eg #cg ,,insulator #ei #ch ,,edwards' ,,condenser #fj #ci ,,edwards' ,,burner #fa #dj ,,edwards' ,,burner #fa #da ,,diagram ,,of ,,edwards' ,,condenser ,,circuit #fb #db ,,circuit ,,for ,,jump ,,spark ,,switch #fd #dc ,,electromagnetic ,,trailer #ff #dd ,,diagram ,,of ,,ruhmkorff ,,coil ,,circuit #fh #de ,,windings ,,of ,,sections #gc #df ,,sectional ,,diagram #gd #dg ,,contact ,,breaker #ge #dh ,,contact ,,key #gf #di ,,fall ,,of ,,potential ,,diagram #gi #ej ,,series ,,arrangement #ha #ea ,,multiple ,,arrangement #hb #eb ,,leclanche ,,cell #hd #ec ,,samson ,,cell #hg #ed ,,new ,,standard ,,cell #ij #ee ,,edison-,,lalande ,,cell #ib #ef ,,fuller ,,cell #id #eg ,,grenet ,,cell #ie ,,chapter ,i4 ,,introductory ,,remarks4 ,the enormous number of fires arising from the use of matches1 and the great convenience and freedom from danger of the electric method of gas lighting1 are alone sufficient reasons for the issue of these pages4 ,the veriest tyro in electrical operations knows that electricity will cause a spark1 and most persons are aware that the spark possesses considerable deflagratory powers1 varying with the character of the spark4 ,in electric gas lighting a spark of the proper character is passed across a jet of gas and ignites it4 ,sparks can be produced by various means3 friction1 battery current1 induction either galvanic or electro-magnetic1 by a ,wimshurst or ,toepler ,holtz machine1 or an induction coil operated by a battery4 ,for our purposes we will consider only the latter2 the former are rarely used1 being uncertain and unwieldy4 ,of batteries there are many kinds1 and although all will produce sparks1 yet for electric gas lighting those made for intermittent work and classed as open circuit cells are to be preferred4 ,open circuit batteries1 which will be fully described in a subsequent chapter1 include the ,leclanche1 and most of the so-called 8dry0 cells4 ,illustration3 ,,fig4 #a4 ,illustration3 ,,fig4 #b4 ,illustration3 ,,fig4 #c4 ,if two wires be attached to a cell of battery ,b1 one to the carbon or positive pole and the other to the zinc or negative pole1 and their free ends be tapped together1 minute sparks at ,c will be observed each time the wires separate 7,fig4 #a74 ,if now a coil of insulated wire ,s be included in the circuit1 ,fig4 #b1 upon repeating the make and break of contact1 the sparks will be much increased4 ,this arises from induction1 each adjacent turn of wire acting upon its neighbor4 ,to better understand the action of induction1 we will consider the following examples3 ,fig4 #c4 ,a is a circuit in which is the battery cell ,b4 ,c is a second circuit lying close to but well insulated from circuit ,a4 ,g is a galvanometer in which a magnetized needle swings right or left each time a current is passed through a coil of wire encircling it4 ,now1 although there is no battery cell in circuit ,c1 yet the needle will swing each time the circuit ,a is closed or opened2 that is1 each time the wire ends are touched together or separated4 ,this swing of course indicates that a current is passing through circuit ,c1 but as there is no battery or other source of electrical energy included in it1 it is clear that it arises from the action of the current in circuit ,a4 ,in point of fact1 the needle swings one way when the circuit is closed and the reverse way when it is opened2 but the greater swing on opening the circuit indicates the greater strength of the induced current at the moment the current ceases to flow in circuit ,a4 ,note that these current impulses are only momentary4 ,in the case of our single coil1 ,fig4 #b1 each turn of wire acted upon itself in a similar manner to the circuit ,a upon circuit ,c4 ,illustration3 ,,fig4 #d4 ,illustration3 ,,fig4 #e4 ,an iron rod or bundle of iron wires1 ,p1 inserted in the coil1 ,fig4 #d1 but carefully insulated from it1 will immensely increase the inductive effects and consequently the spark4 ,this arrangement constitutes the simple primary coil used in pull-down or pendant and automatic burners4 ,this spark is often a source of inconvenience2 it appears wherever a circuit including similar coils is made and broken4 ,in telegraph apparatus at key and relay contacts it is noticeable2 in fact1 the writer has used temporarily a pair of electro-magnets from a telegraph sounder and obtained spark enough to operate a gas lighting burner4 ,to produce a long spark which will jump across an air gap1 a more complicated form of coil is needed1 one which more closely corresponds to the experiment noted in ,fig4 #c4 ,the simple primary coil has here another coil of finer wire1 ,s1 wound on it but carefully insulated from it 7,fig4 #e74 ,this second coil1 or 8secondary10 has a vast number of turns of fine wire as compared with the primary1 which has only comparatively few turns of coarse wire4 ,a primary coil of #dj feet of ,no4 #ad ,b4 ,s4 copper wire would be inserted in a secondary coil of perhaps #af1jjj feet of ,no4 #cf ,b4 ,s4 ,this secondary coil1 in fact all the apparatus constituting the induction coil1 must be most highly insulated1 as the electromotive force of the spark is tremendous1 and it would be liable to pierce its way through and into the internal winding and so destroy the apparatus4 ,the circuit in the primary is made and broken either by a hand key or by an automatic contact-breaker at ,c4 ,with a large coil1 the intensity of the spark at ,g is such that it will jump an air-gap of from one-eighth of an inch to over three feet4#a #a ,see ,norrie1 ,induction ,coils and ,coil-,making4 ,this combination of coils and contact-breaker is generally known as a ,ruhmkorff or intensity coil1 and is shown in elevation in ,fig4 #f4 ,illustration3 ,,fig4 #f4 ,,chapter ,,ii4 ,,multiple ,,gas ,,lighting4 ,illustration3 ,,fig4 #g4 ,as we have already seen how a spark is exhibited at an interrupted contact1 the means of its application to gas lighting will be considered4 ,fig4 #g represents the most generally used kind of electric gas burner or 8pendant burner40 ,its application is shown in ,fig4 #h4 ,the wire ,w from the coil ,c is attached to the brass insulated collar carrying the contact ,s4 ,the other wire from coil ,c and battery ,b is attached to the gas pipe ,g4 ,as the burner is also screwed into the gas pipe itself1 the circuit would be closed were it not for the gap at ,a on the burner1 caused by the collar carrying the contact ,c and wire ,w1 being insulated from the burner pillar ,p4 ,when1 however1 a pull is given to the burner arm chain so as to cause the end of the spring ,r to strike contact ,c in passing1 contact is made and broken1 and a spark passes which ignites the gas issuing from the burner tip1 the gas having previously been turned on4 ,a piece of chain with a metal ball is attached to the burner arm in order to pull it down4 ,in this class of burner there are many different makes differing only in minor details4 ,illustration3 ,,fig4 #h4 ,fig4 #i shows a form of pendant burner which has no platinum contact1 but has a broad lug on the insulated collar which is scraped against by the spiral spring when the arm is pulled down4 ,it will be seen that the lug is not held by an insulated collar on the burner top1 but is on the extension of an arm attached to the burner pillar by a large screw and insulating washers4 ,the circuit wire goes under the smaller screw seen on the lower part of the contact arm1 this forming a strong and neat form of attachment4 ,illustration3 ,,fig4 #i4 ,now it has heretofore been necessary to turn on the gas before pulling the chain of a pendant burner1 but as this is not always desirable the ratchet burner is made4 ,fig4 #aj shows burner carrying a toothed wheel1 which is partly rotated when the arm is pulled down4 ,this wheel is mounted on the stem of a valve which opens or shuts according to the point of rotation1 and thus shuts off or admits the gas to flow up to the burner4 ,one pull of the arm turns the gas on2 at the same time the wipe spring touches the contact on burner collar1 and the gas lights4 ,a second pull and the wheel1 rotating1 turns off the gas4 ,in all burners of this class a spring is provided to carry the arm up and back into its original position ready for another pull4 ,some burners do not make contact when the arm flies back1 thus saving battery current4 ,illustration3 ,,fig4 #aj4 ,illustration3 ,,fig4 #aa4 ,fig4 #aa is an improved form of burner wherein the movable electrode does not pass through the gas flame1 neither do the electrodes come in contact with each other when the gas is being turned off4 ,reference to the cut will show a pin protruding from the base of the coiled spring electrodes1 which pin is so arranged as to come in contact with the short end of the pull-arm4 ,when this pull-arm is pulled down it pushes up this pin1 elongating the spiral spring electrode sufficiently to make and break contact at the fixed electrode on the burner collar4 ,this burner can be fitted with a porcelain candle slip if desired to match the imitation candle burners4 ,,stem ,,burners4 ,objection is sometimes made to the ordinary chain pulls from the fact that they jar the fixtures1 and also are liable to bend the fixture branches from the strain used in operating the arm4 ,to overcome these objections the stem style of burner is manufactured 7see ,fig4 #ab74 ,this stem1 it will be seen1 carries a convenient key at the end1 which is turned either right or left as in an ordinary gas-cock4 ,the moving contact only makes contact when the gas is being turned on and lighted4 ,when turning it off1 the arm is retracted so as not to touch the fixed electrode1 thus saving battery current4 ,illustration3 ,,fig4 #ab4 ,fig4 #ac is a simple lighting attachment for an ,argand burner4 ,the moving lever which carries the pull has a ,german silver spiral spring on its top end4 ,this strikes against the lug projecting from the circuit-wire arm and makes a spark4 ,the lower part of the circuit-wire arm has a screw and washers for ready attachment1 and is strongly and substantially made4 ,illustration3 ,,fig4 #ac4 ,a means of igniting the gas from a ,welsbach burner is shown in ,fig4 #ad1 and is so simple as to need no further explanation4 ,,acetylene ,,burners4 ,owing to the deposits of carbon1 it is necessary to construct burners for acetylene gas in a different and more substantial manner than those designed for coal gas4 ,illustration3 ,,fig4 #ad4 ,the best arrangement is depicted in ,fig4 #ae1 which has a pilot-tube burner as well as the two main tips4 ,on turning the key1 gas is admitted to both main and pilot burners1 but the electrode in breaking contact only ignites the gas at pilot burner1 which1 in its turn1 acts as a lighter for the main burner4 ,turning the main burner out1 the pilot light can be left burning if desired1 giving a small light1 it being not feasible to turn down the main burner owing to the before-mentioned carbonization4 ,illustration3 ,,fig4 #ae4 ,the orifice of an acetylene burner is much smaller than that of a coal gas burner1 the former burning about one-half foot per hour1 against six or seven feet of the latter4 ,,burners ,,for ,,gasolene4 ,the flame from this gas is hotter than that of coal gas1 and deposits so much more carbon that a slight modification is necessary in the construction of burners for it4 ,the details can be readily seen on observation of a burner1 being simply in the adjustment of the contacts and their operation4 ,it is better1 however1 to use a larger coil and a stronger battery for gasolene gas lighting than would be needed for coal gas--say1 #f cells of ,samson1 or large-size ,new ,standard dry battery and a #aj-;inch coil having about #d pounds or more of wire on it4 ,,automatic ,,burners4 ,illustration3 ,,fig4 #af4 ,there are several forms of these burners1 but the principle of all is the same4 ,a gas burner protrudes from the top of a brass case which encloses the actuating mechanism4 ,this mechanism consists generally of two electro-magnets1 the armature of one opening the valve and allowing the gas to flow1 at the same time vibrating a platinum-tipped rod against an electrode upon the burner collar4 ,this produces a series of sparks at the burner tip which ignites the gas4 ,a second magnet is provided which shuts the valve and extinguishes the gas4 ,some devices use one electro-magnet to both open and close the valve1 but the majority have double electro-magnets4 ,the circuit is worked from a push button1 ,fig4 #af1 situated wherever desired2 pressure on a white button lights the gas and on a black one shuts it off4 ,,bartholdi ,,automatic ,,burner4 ,instead of a rotating stop-cock1 as in other automatics1 a gravity valve is employed in the ,bartholdi1 which is held to its seat by the weight of the armature and connecting stem1 as shown in figure #ag4 ,when the gas is turned off the valve rests upon its seat1 as indicated in the cut4 ,by a closure of the electric circuit at the turn-on button1 two of the helices ,m ,p are energized1 causing the armature ,j to be lifted1 thus1 by means of the stem ,h1 raising the valve ,g from its seat into the dotted position1 and opening the gas way so that the gas may issue to the tip1 as shown by the arrows4 ,at the same time1 the top of the valve strikes against the end of the lever ,w1 causing the circuit to be broken at the spark points ,t ,u1 resulting in a continuous sparking as long as the finger presses the button4 ,the magnet when raising the armature has also twisted or partially revolved it1 so as to bring the notch d in the armature over the end of the hook e1 as shown in the dotted lines4 ,when the circuit is broken by lifting the finger from the button1 the notch falls into the hook and the valve is locked open4 ,illustration3 ,,fig4 #ag4 ,to extinguish the flame1 the turn-off button is pressed1 when a second magnet 7not shown in cut7 lifts the armature and twists it in the opposite direction1 so that when the circuit is broken the armature falls free to its normal position1 closing the valve4 ,illustration3 ,,fig4 #ah4 ,,the ,,advance ,,automatic4 ,this automatic burner1 ,fig4 #ah1 is typical of the class having two magnets1 one to open valve and light gas1 and another to close valve and extinguish the light4 ,it embodies an improvement over the older types of burners in that the binding posts are mounted on a rubber strip held by two screws1 thus preventing the twisting and loosening so common heretofore4 ,it also allows of the valve being opened and gas lighted by means of a match should the battery fail4 ,,vibrator ,,burner4 ,this is an automatic burner which has no valve mechanism1 but ignites the gas only4 ,it is generally placed in a cluster or ring where the burners are close enough to light by contagion4 ,it is much smaller in diameter than the regular automatic burners1 being but one and three-quarter inches in diameter4 ,,argand ,,automatic ,,burners4 ,automatic burners are also made for ,argand1 but present no radical difference in construction over the regular type4 ,,the ,,concealed ,,automatic ,,burner4 ,illustration3 ,,fig4 #ai4 ,this automatic1 ,fig4 #ai1 consists of two iron-clad magnets1 placed one above the other1 between which is located a gas valve4 ,through an extension of the latter a pin is driven1 one end acted upon by the upper armature to open the valve and ignite the gas1 the other by the lower armature which serves to close the valve and extinguish the flame4 ,around the burner is placed a porcelain candle slip of #c_/d-;inch diameter and from #d-c_/d inches in length upwards4 ,,chapter ,,iii4 ,,connections ,,and ,,wiring4 ,fig4 #bj shows how to connect up an automatic burner with two pushes2 thus one can be downstairs in the hall and the other upstairs1 allowing one to either extinguish or light the gas from either place4 ,the value of this arrangement is obvious2 it allows one to light up the hall before descending at night1 or to put out the gas after one is safely upstairs4 ,again1 an automatic burner can be put in the cellar and lighted and extinguished from the head of the cellar-stairs1 saving matches and danger of fire4 ,fig4 #ba shows the connections of one automatic burner and two pendant or rachet burners4 ,p ,p are the pendent burners1 ,a the automatic burner1 ,c the primary coil1 ,s the buttons which control the automatic burner1 ,m ,m ,m the cells of battery1 of which there should be at least four1 if not six4 ,a low-resistance cell must be used here1 as before mentioned1 one that gives not less than #e amperes on short circuit4 ,it will be seen here that one side of the battery is connected to ground 7or gas pipe71 the circuit being completed owing to the burners being themselves screwed into the gas pipe4 ,care must be taken1 however1 to first see that no insulating bushings have been used at the gas fixtures1 as is done in wiring for electric light4 ,in this case a double circuit will have to be run4 ,illustration3 ,,fig4 #bj4 ,illustration3 ,,fig4 #ba4 ,in wiring up an automatic burner with two electro-magnets1 two wires are run1 one from the black button and one from the white button on push-plate4 ,most burners have binding posts inside the case1 the wires running through a rubber-bushed hole in the base4 ,one of the greatest defects in the old style automatics arose from the two binding posts being fixed on a hard rubber block1 which was held by one screw to the burner top4 ,this screw got loose at times and the block used to twist1 making it hard to tighten the wires4 ,but improvements have been made in this direction1 the later burners having a block with a projection which engages in a hole in the cover1 and is held by two screws4 ,if the push has been set in place1 and all wiring done1 connect up the burner1 first ascertaining to which binding post the two wires run4 ,this is done by having one button pressed1 the lighting 7white7 one1 for example1 and then touching the binding post with either wire4 ,the lighting armature will buzz violently when touched1 whereas the extinguishing one only strikes once when contact is made4 ,when only one person is working1 a pin can be wedged in the push so as to keep the circuit closed4 ,in setting up these burners care must be taken not to bend contacts or alter adjustments1 and absolute precaution is necessary that no wires touch where uninsulated4 ,a cause of trouble is a dirty burner which does not allow the gas to strike the contact spark4 ,the collar carrying the second contact may shift1 or perhaps become short-circuited in a pendant or ratchet burner2 a strip of asbestos will remedy this4 ,,burner ,,distribution4 ,in fitting a house with electric lighting burners1 the question of selection is best solved as follows3 ,for the main hall and foot of the cellar-stairs1 use the automatic burner4 ,for other hallways1 dining-room1 drawing-room1 and bathroom use ratchet burners which turn on and light gas when chain is pulled4 ,for bedrooms use plain pendant burners2 automatics and ratchets add an element of danger1 in that they may not turn off gas1 or may leak4 ,most of this type on the market are as reliable as it is possible to make them1 but still accidents will happen4 ,the frontispiece shows a diagram of the wiring in a dwelling house of medium size1 dividing it into three sections1 each section being controlled by a switch--either a hand switch or one of the automatic cut-out switches elsewhere described4 ,the burners are distributed as follows3 ,no4 #a in the front cellar1 pendant or ratchet4 ,no4 #b in the rear cellar at foot of stairway is an automatic burner controlled from kitchen above4 ,nos4 #c and #d ratchet burners on chandeliers in drawing-room and dining-room4 ,no4 #e ratchet or pendant in kitchen4 ,no4 #f pendant in bedroom4 ,no4 #g ratchet or pendant in bathroom4 ,no4 #h pendant in bedroom4 ,no4 #i pendant in bedroom4 ,nos4 #aj1 #aa1 and #ab pendants in bedroom4 ,no4 #ac automatic burner in hallway operated from pushes in lower and in upper hallways4 ,the articles required for this job are as follows3 ,two automatic burners4 ,three gas lighting push-buttons and bases4 ,pendant and ratchet burners according to number of lights in rooms4 ,six cells--open circuit battery4 ,one three-lever switch4 ,one #h or #aj inch spark coil4 ,three pounds ,no4 #af patent finish office wire4 ,two ounces ,no4 #bd gas-fixture wire4 ,one pound tinned #c_/h staples4 ,few square inches tinfoil4 ,small roll insulating tape4 ,tools3 #d-;inch screwdriver1 pocket knife1 #d-a_/b-;inch side-cutting pliers1 hammer1 piece of sandpaper4 ,the simple section switch is shown enlarged in ,fig4 #bb4 ,the wires #a1 #b1 and #c are from their respective circuits and terminate at the switch arms ,a ,a ,a4 ,the wire from the battery ,b and coil ,c runs to each switch-stud ,s ,s ,s4 ,if trouble shows on the line1 each circuit can be thrown off by moving its switch arm until the fault is located4 ,if it is not found at once1 and the battery is weak1 7test each cell with an ordinary electric bell71 open all the circuits until the battery is recuperated1 and disconnect the battery wire from the switch4 ,then attach the battery wire to the bell and touch each switch lever with a wire from the other binding post of the bell4 ,if there is a short circuit on any section1 the bell will ring or tremble when the arm is touched4 ,illustration3 ,,fig4 #bb4 ,on the contrary1 if the burners fail to work and no sign of a short circuit can be thus obtained1 it is evident that a wire is broken or a screw is loose4 ,to locate a break1 connect up the bell as just described and attach the testing wire to the switch with all levers closed2 this is actually putting the bell in series with the battery1 coil1 and ground4 ,then hunt for the break4 ,take a long piece of wire and fasten one end to a ground pipe4 ,then touch the other end to the circuit wire in the cellar as far as you can go1 baring the insulation in spots1 but carefully re-insulating it again4 ,if there is no break in the cellar1 the bell will ring loudly at each contact4 ,next1 proceed to the next floor and repeat the operation1 gradually working away from the battery4 ,as soon as you pass the break1 the bell will fail to respond4 ,two persons here are better than one1 as it may be necessary to go quite a distance from the bell before finding the trouble4 ,fig4 #bc shows details of the wiring from the hall light to the two push-buttons4 ,a wire is run right down from the top push ,t1 middle connection1 past the lower push ,l1 where a similar branch joins it1 until it reaches the section switch4 ,the lighting and extinguishing wires from the lower push run up and are joined on to the similar wires from the top push1 which latter wires go directly through the floor and ceiling to the automatic burner ,a4 ,illustration3 ,,fig4 #bc4 ,illustration3 ,,fig4 #bd4 ,fig4 #bd is the detail of the wiring for the cellar automatic burner ,a1 from the push ,p1 and is so clearly shown as not to require further explanation4 ,the secret of success in gas-lighting work is careful wiring4 ,the platinum tip of the vibrating rod is often bent1 either by accidental blow or by the continual hammering against the tip on the collar4 ,this often causes an open circuit when the lighting armature refuses to buzz4 ,again1 soot will form1 causing weak action owing to imperfect contact4 ,examine1 adjust1 and clean2 here1 as in all electrical work1 contacts must be clean4 ,in general wiring1 use weatherproof office wire1 or1 better still1 well-made electric light wire4 ,for ordinary house work ,no4 #af ,b4 ,s4 gauge is preferable2 smaller wire means higher resistance and less current at burner4 ,for braided office wire1 ,no4 #af runs about #ie feet to the pound1 ,no4 #ah about #ace feet to the pound4 ,the cheaper grades of wire without the patent finish or extra insulation are not worth using2 sooner or later trouble will ensue1 and once a house is wired1 it is no pleasant job to hunt trouble1 especially if the wire was put on before the plaster4 ,in modern buildings in large cities1 the use of conduit tubes has become general1 but the handling of these conduits comes more under the province of the electric-light wireman and less within the scope of these pages4 ,in wiring new wooden buildings do not draw wires too tight2 the wood may expand and either break wire or cause a weakening of the insulation4 ,in wiring before the plaster is put on1 always leave a good length free1 so it will not be covered up by the plasterers4 ,the wire used on the gas fixture is of a special kind1 being made for the purpose4 ,it is made in two sizes1 ,no4 #bb and ,no4 #bd ,b4 ,s4 gauge1 and with three windings of cotton1 three outer layers of cotton and one of silk1 or three windings of cotton which is soaked in fireproof preparation1 and then wound with silk4 ,as the piece used is generally short1 these small sizes are sufficient in carrying capacity4 ,after wiring up a fixture1 this fine wire can be tied on to the pipes1 etc41 with thread1 and a good coating or two of shellac varnish applied4 ,when this is dry1 the thread can be removed and the shellac will hold the wires on to the fixture4 ,on no account finally connect up the battery to a circuit when shellacking the wire4 ,wait until the shellac is thoroughly dry and hard--at least half a day1 if possible4 ,white lead is generally used at the joints where the burner screws into the fixture1 but tinfoil wrapped round the joint will give good service4 ,it prevents leaks and ensures a good contact4 ,the ground connection at the battery must be first-class2 do not be content with just wrapping a few turns of wire around the pipe in the cellar 7assuming the battery is in the cellar71 but clean and scrape the pipe2 clean at least two feet of the wire1 wind it tightly and evenly on the pipe and solder it4 ,there is a pipe-clamp made which is clamped on the pipe and the wire attached to that1 but it must be properly put on a clean surface4 ,,wiring ,,finished ,,houses4 ,in wiring finished houses1 especially wooden ones1 the wires can be run along skirting boards1 and often pushed out of sight in the space between the floor and the skirting4 ,this is quite permissible1 as the wires1 unlike electric-light wires1 carry no dangerous current2 but waterproof wire becomes preferable1 as the water used in washing a floor will often creep under and rot the insulation4 ,in going upstairs1 wires can often be run in the fluting of a moulding along the stairway1 and be quite inconspicuous2 but wherever possible1 fish the wires up inside the wall4 ,the main thing to be considered in wiring is that the wires are large enough1 well insulated1 all joints well made and taped and put where there is no danger of injury4 ,rats have a habit of gnawing paraffin-coated insulation1 and it is well to run such in metal tubes4 ,in joining or splicing wires1 do it in a thorough manner1 and solder if possible4 ,never use the old bell-hanger joint--the one in which the ends of the wires are merely looped together4 ,strip insulation and scrape or sandpaper bright about three inches of each wire to be spliced4 ,then1 placing the bare wires across each other about three-quarters of an inch from the insulation1 tightly wind the loose bare ends of each around the bare inside portion of the one it is being spliced to4 ,a touch of solder will prevent trouble from oxidation1 after the adhesive tape has been wrapped on4 ,attention to details like these will often ensure the satisfactory working of the job4 ,a handy tool for gas-lighting wiring is shown in ,fig4 #be4 ,one end is bored out to fit the small nuts on the ratchet and pendant burners1 and the other is filed flat for use as a screwdriver4 ,illustration3 ,,fig4 #be4 ,a case may arise where there is electric light on the same chandelier as the gas lights1 and that an insulating bushing has been screwed in between the fixture and the pipe4 ,in this case it will be necessary to run two wires to each burner1 the pipe common return being now unavailable4 ,another scheme is to interpose an insulating bushing under each burner2 then the second or return wire need only be run from the burner to the gas pipe outside the main bushing4 ,but the local fire-insurance rules must first be consulted4 ,most ceiling gas fixtures will admit of the fixture wire being run inside the brass shell1 which makes a neater job4 ,but the very best of insulation must be used1 and great care be taken that it be not abraded4 ,it should be shellacked or otherwise insulated before use4 ,the electric-light fixture wires are admirable for use here if there is room4 ,for concealed work in a finished house1 locate the position of the fixture under the floor of the room above by measuring both in the room where the fixture is and in the room above4 ,then cut out a piece of the floor1 drill up from underneath through the fixture plaster-rose with a fine drill1 and push the fixture wire up4 ,the main wire can be laid under the carpet1 or along the floor-crack in the upstairs room4 ,in wiring up wall-fixtures1 push-buttons1 etc41 it is often possible to fish the wire up from the floor by punching a hole at the fixture and inserting a piece of chain 7made for the purpose71 attached to a long and stout thread4 ,then drill into the skirting near the floor plumb underneath the first hole and fish for the chain with a piece of wire having a hook on the end of it4 ,where fixtures have brass rosettes1 these can be removed by 7generally7 unscrewing the fixture1 but first shut off the gas at the meter1 or plug the hole2 this may seem unnecessary advice1 but experience warrants its being given4 ,when the chain is fished out1 a piece of wire can be attached to the thread and pulled through in turn4 ,in most cases its point of exit at the fixture can be concealed by the rosette1 through a hole in which it passes4 ,take care that the edges of this hole do not cut the insulation4 ,care must be taken at every step in gas-lighting wiring4 ,in wiring up a push-button1 screw all wires tightly under their respective binding screws1 and then cover wherever possible with adhesive tape4 ,as the wires must be somewhat loose to allow of the connections being made at the back of the push-button at the wall1 they will have to be carefully pushed into the hole1 and if they are not tightly held by screws1 trouble will result4 ,it is a good plan1 when using fine enough wire1 to make a sort of eye at the end of the wire and pass the screw through this1 instead of merely giving the wire end a turn around the screw and then driving the screw home4 ,of course washers should be used wherever an ordinary screw holds a bare wire4 ,,automatic ,,burner ,,operated ,,by ,,door4 ,one of the uses to which an automatic burner can be put is in conjunction with an electric door-spring1 lighting when the door is opened1 but preferably extinguished by independent push4 ,in this case1 a form of trip spring should be used which would only make contact during a portion of the travel of door4 ,such a trip is shown in ,fig4 #bf4 ,a is automatic burner2 ,c1 the primary coil2 ,b1 the battery2 ,t1 a swinging trip piece of brass hinged in brass plate1 ,p1 which is screwed over the door in such manner that the door opening in direction of the arrow will cause the trip ,t to strike against the spring ,s1 and make contact4 ,this spring is insulated from the plate ,p by the hard rubber block ,r4 ,on the door being opened1 the trip will make contact long enough to light the burner and will then fall back as the door passes4 ,on shutting the door1 the trip will be raised and will fall as the door passes1 but will not make contact4 ,or1 if so desired1 it can be made to operate a second contact to extinguish the burner by fixing a second insulated spring so it will be pressed when the top of trip makes a downward movement--as when the door passes it in shutting4 ,illustration3 ,,fig4 #bf4 ,various applications of automatic burners in connection with burglar alarms will suggest themselves1 but in these cases the utmost care must be taken that the apparatus is in good working order2 failure to light might cause the room to be filled with gas1 and serious results ensue4 ,for those persons who use gas stoves and are mechanically inclined1 an arrangement of an alarm clock with an automatic burner will enable them to light up without getting out of bed1 or perhaps even waking up4 ,,chapter ,,iv4 ,,primary ,,coils ,,and ,,safety ,,devices4 ,to construct a primary coil such as used with pendant or automatic burners presents no difficulty4 ,the most convenient sizes are those #h to #aj inches in length and about #c inches in diameter4 ,it is quite common to speak of these coils as #h or #aj inch coils2 to the writer's knowledge this has been taken to mean a ,ruhmkorff or double-wound induction coil1 giving a free #h or #aj inch spark4 ,illustration3 ,,fig4 #bg4 ,to make such a coil 7,fig4 #bg71 proceed as follows3 ,prepare a spool by gluing a paper or fibre tube #c_/d inch in outside diameter by about #a-af inch thick into square or round spool ends three inches square1 one-half inch thick1 and having each a centre hole just large enough to admit of the tube being held tightly4 ,these ends should be firmly fixed on the tube2 a pin or two driven through tube into end will assist in strengthening the joint4 ,now wind on the tube about #c pounds ,no4 #ab ,b4 ,s4 cotton-covered magnet wire4 ,this will give about six layers of #hj turns each1 nearly #ejj turns in all1 a total length of1 say1 #aej feet1 measuring 4#be ohm4 ,the ends of the wire are to be brought out through holes drilled in the spool ends1 and can be fixed to brass binding posts on those ends4 ,into the paper tube push as many iron wires #h inches long by ,no4 #bb ,b4 ,w4 gauge as will fill it4 ,these iron wires can be tightened finally by driving in at each end1 a stout wire nail4 ,although not absolutely necessary1 a coat or two of shellac varnish applied to the windings will make a better insulation4 ,shellac varnish is readily made by dissolving one part gum shellac in four parts of alcohol4 ,for coils which are likely to be in damp places1 a good saturation with insulating compound1 such as ,p4 ,b4 paint1 will render them waterproof4 ,the need for good insulation in these primary coils is not so urgent as in ,ruhmkorff coils1 owing to the lower potential of the current4 ,a smaller coil can be made with ,no4 #ad ,b4 ,s4 wire where the battery is of higher resistance 7or gives less than ten amperes on short circuit74 ,the remarks on battery selection on another page will be found to meet application here4 ,,automatic ,,cut-,,outs4 ,where there are a number of burners to be installed in different parts of a house1 it becomes desirable to wire in a number of circuits4 ,as one end of the circuit is already grounded1 a second ground will cause material injury to the battery if not detected in time4 ,it becomes1 therefore1 necessary to be able to open a grounded circuit without affecting all the lights in a house4 ,this is possible with the multiple circuit arrangement by using a switch1 either automatic or operated by hand4 ,the simplest form of danger signal is the relay electric bell attachment1 which device is mounted on the end of the gas-lighting coil4 ,it consists of an armature which closes a circuit when attracted by the coil core1 in which circuit are included a battery and electric bell4 ,now when an ordinary pendant or ratchet burner is pulled1 it only sends a momentary current through the coil1 enough to magnetize the core1 but not enough to attract the armature sufficiently long for the bell to ring4 ,but if a short circuit or ground should occur1 the armature is held against the contact long enough to cause the bell to ring and give warning4 ,in some cases a constant ringing attachment is added1 in which case the bell rings until some one stops it4 ,,the ,,syracuse ,,cut-,,out4 ,this is a most ingenious device for opening a short circuit1 depending on its action upon the sluggish movement of glycerine 7,fig4 #bh74 ,a sealed glass tube pivoted near its centre contains a portion of glycerine sufficient to considerably overbalance it and keep one end down4 ,a soft iron armature is attached to this tube in such manner that each time a current flows through a pair of electro-magnets1 the attraction of the armature causes the tube to tilt and the glycerine flows along to the other end4 ,now it will be readily seen that if the tube is only tilted for a second or so1 the slow-moving glycerine will not have flowed sufficiently to the end to overbalance it1 but it requires an attraction of the armature for a considerable period4 ,this electro-magnet is in circuit with the gas-lighting wires1 the tube being provided with contacts in such manner that1 when fully tilted1 the circuit is broken4 ,the momentary jerks imparted to the armature by the operation of a pendant or automatic burner will not be enough to permanently tilt the tube and break contact1 but a short circuit will hold the armature tight down1 until the increasing weight of glycerine causes the tube to open the circuit4 ,illustration3 ,,fig4 #bh4 ,illustration3 ,,fig4 #bi4 ,,automatic ,,sectional ,,cut-,,out4 ,illustration3 ,,fig4 #cj4 ,this cut-out1 ,fig4 #bi1 is representative of the class which use clockwork1 and is both simple and reliable4 ,the house circuit is in series with an electro-magnet which controls a clockwork having a long pinion shaft4 ,this clockwork starts and runs while the house circuit is closed1 as on operating a burner1 but stops when the circuit is opened and flow of current ceases4 ,the wires leading to different circuits in the building run through a number of contact springs mounted on sliding rods1 which have teeth cut on the under side 7,fig4 #cj74 ,these rods have soft iron armatures on the opposite ends from the contact springs1 which rest over electro-magnets1 also connected to the house circuits4 ,when the clockwork starts1 the pinion shaft revolves1 but does not engage in any of the sliding rods1 as they just clear it4 ,should a heavy or continuous current pass through one of the electro-magnets1 it attracts the armature on the corresponding rod 7,fig4 #ca71 and the turning pinion engages in the teeth1 drawing up the rod and breaking contact4 ,illustration3 ,,fig4 #ca4 ,fig4 #cb is a form of battery protector which works on the gravity principle4 ,here each section is governed by a rocking contact1 operated by two glass bulbs partially filled with a volatile fluid 7such as ether71 and joined by a glass tube4 ,in one of these bulbs is a platinum wire which is included in the circuit and heats upon the passage of a strong or continuous current4 ,if the circuit is closed too long1 the heating of the platinum wire causes the fluid to flow into the upper bulb1 and1 as the bulbs are pivoted1 the increased weight of the upper bulb now overbalances the rocker and breaks the circuit on that section4 ,illustration3 ,,fig4 #cb4 ,,chapter ,v4 ,,lighting ,,of ,,large ,,buildings4 ,the jump spark system is used where it is desired to light clusters of gas jets situated in inaccessible places1 or a number of them simultaneously4 ,the spark from a ,ruhmkorff coil1 being made by a contact broken at the coil and not at the burner1 can be divided up among a number of simple burners placed in series4 ,one of the burners used and known as the ,smith jump spark burner is shown in ,fig4 #cc4 ,the wires from the coil are attached to the electrodes shown on each side of the burner1 and the spark jumps across the gap1 situated nearly over the burner orifice4 ,there is a guard-flange of mica round the lower part4 ,fig4 #cd shows the manner in which the jump spark is applied to a ,welsbach burner4 ,a small porcelain clip carrying the spark-gap wires is held on the top of the burner chimney4 ,the electrodes project down into the chimney so that a draught of air cannot carry the stream of gas away from the spark-gap4 ,illustration3 ,,fig4 #cc4 ,illustration3 ,,fig4 #ce4 ,illustration3 ,,fig4 #cd4 ,fig4 #ce shows a burner intended for the stage of a theatre1 or where the lights are located in dangerous and inaccessible places4 ,the burner is made of porcelain upon which are spun the metal top and bottom4 ,one electrode is also clamped around it1 allowing of adjustment and better insulation4 ,illustration3 ,,fig4 #cf4 ,these burners are used in series1 as shown in ,fig4 #cf4 ,b ,b ,b are the burners2 ,s ,s1 the secondary wires from the ,ruhmkorff coil1 ,i2 ,p ,p1 the primary coil wires from battery1 opened and closed by means of the key1 ,k4 ,it is often possible to place plain burners close enough so that they can ignite by contagion4 ,in this case one of the plain burners is removed and replaced by a multiple burner1 as above4 ,it is customary to allow sixteen burners to one inch of spark1 in which case the spark gaps are adjusted about one-sixteenth of an inch apart4 ,a coil giving a #b-;inch spark would operate #cb burners1 but actually it would be found preferable to omit a few1 so as to make allowance for any slight leak4 ,a spark of over #b inches is hard to handle1 although often used2 it is better to make up a number of circuits of1 say1 #cj burners each1 and operate them alternately by a suitable switch4 ,the wire used to connect the burners is generally bare1 although an insulated wire is sometimes used4 ,but the electromotive force of a #b-;inch spark is so high that it is better to run the wires so they do not come near anything liable to cause a leak4 ,the remarkable tendency of these high-tension currents must be most carefully guarded against2 indeed1 it is what makes this style of gas lighting so often unsuccessful4 ,a damp wall1 gilt wall-paper1 a gas pipe hidden in the plaster1 will often lead off the current4 ,the wires should be at least #ej per cent4 further off from any object than the spark length2 that is1 a #b-;inch spark circuit should be at least #c inches away from a wall1 and the further the better4 ,it cannot be too strongly urged that every precaution be taken to keep the wires away from objects other than their insulators4 ,illustration3 ,,fig4 #cg4 ,fig4 #cg shows the special form of insulator used4 ,it is made of the highest grade glaze filled porcelain1 and the screw is passed into it and holds against the lower end as far away from the wire as possible4 ,glass tubes should be passed over the wires wherever they come near any metallic object1 that is1 within sparking distance4 ,,edwards' ,,condenser ,,system4 ,this system differs from the foregoing in that the spark-gaps are connected in multiple1 instead of series1 and each burner is provided with a small but efficient condenser4 ,illustration3 ,,fig4 #ch4 ,it prevents trouble should a wire break between burners1 in which event only one burner would be out of commission1 whereas in the first method1 the whole number in that series would suffer4 ,it is also more sure in action and presents less liability of the spark jumping to the ground4 ,the burner pillars need not be made of porcelain or lava2 in fact1 the electrodes can be readily attached to the existing burner4 ,fig4 #ch is a condenser consisting of a small oval piece of mica1 on each side of which is fastened1 with insulating varnish1 a spatula-shaped piece of tinfoil4 ,one foil sheet is attached to the line1 the other to the burner electrode4 ,these condensers must not be allowed to get wet or their efficiency will be impaired4 ,illustration3 ,,fig4 #ci4 ,illustration3 ,,fig4 #dj4 ,figs4 #ci and #dj are the most generally used burners1 the wire from the condenser being attached to the lug or top electrode1 which is insulated from the burner by means of the mica plate to which it is riveted4 ,the burner pillars are of course grounded through their being screwed into the gas pipe4 ,the circuit is shown in ,fig4 #da4 ,i is the induction or ,ruhmkorff coil1 in the primary circuit of which is the key1 ,k1 controlling the current from the battery1 ,b1 and across which is bridged the condenser1 ,c ,c4 ,when the coil vibrator is used1 the condenser ,c ,c can be omitted1 that of the coil itself serving instead4 ,s is the wire leading from the secondary terminal of the coil to the burner condenser1 ,c1 which1 in turn1 are connected to the electrodes on the burners1 ,p ,p1 as before noted4 ,the other secondary wire is grounded preferably to the gas pipe itself4 ,illustration3 ,,fig4 #da4 ,where a lot of burners are placed together1 as in a ring1 it is often feasible to light them by contagion1 one tip only being connected to the coil circuit1 the others lighting from it and conveying the flame around to the rest4 ,this avoids multiplicity of circuits1 or1 perhaps1 too many burner gaps on one circuit2 but the one burner may fail to light1 whereas1 where all are fitted1 the chances of failure are less1 especially in the ,edwards condenser system4 ,,switch ,,for ,,jump ,,spark-,,lighting4 ,in a switch for controlling the current of the secondary coil it will be evident that the utmost attention must be paid to matters of insulation4 ,the object of such a switch is to control a number of circuits2 for example1 as it is not advisable to put more than #bj to #be burners on one circuit1 a case requiring the lighting of #ajj burners would necessitate some means of passing the current to each circuit in turn4 ,this is shown in ,fig4 #db1 in which ,s is a hard rubber plate1 provided with a revolving metal arm and handle1 ,h1 and four contact points1 ,p1 which latter receive the ends of the wires from the groups of burner condensers ,b by means of nuts or binding posts4 ,the wire from the secondary of the coil is run to the switch-handle1 ,h1 great care being taken that it does not pass near to the circuit wires1 or contact points4 ,revolving the switch-handle connects the secondary wire to each circuit in turn4 ,it will be noticed that1 unlike a battery switch1 this one has a large base1 long switch-arm1 contact points situated far apart1 and every precaution taken to control the passage of the high-tension current4 ,the base should always be of rubber or glass4 ,shellacked-wood1 or such substitutes1 are productive of trouble4 ,illustration3 ,,fig4 #db4 ,when it is desired to light automatically a number of burners from a distance1 the ,trailer 7,fig4 #dc71 is used4 ,this is a switch similar to above1 but the arm is revolved by means of toothed wheels by the electro-magnet shown on the back4 ,as it is never desirable to unnecessarily prolong the secondary wires1 this device admits of the switch being put near the circuits1 and yet being operated from afar4 ,illustration3 ,,fig4 #dc4 ,,ruhmkorff ,,coil4 ,fig4 #dd shows a diagram of a ,ruhmkorff coil1 the letters referring as follows3 ,c the iron core1 ,p the primary coil wires1 ,i the insulating tube between primary ,p and the secondary coil ,s4 ,in small coils this may be dispensed with1 and a heavy layer of paraffin wax laid over the primary coil4 ,d ,d are the ends of the secondary1 showing sparking taking place between a pair of balls 7or between the electrodes of a gas burner72 ,r is a stiff spring fastened to the coil base and carrying a soft iron hammer1 which is attracted toward the iron core1 ,c1 when current passes through the primary coil and magnetizes it4 ,l is a battery1 ,j1 a condenser1 to be more fully described later on4 ,when the spring ,r touches the adjustment screw ,a at ,b1 as they are insulated from each other1 contact is made and reference to circuit will show that the current from battery ,l flows through primary coil1 magnetizing the core and attracting soft iron hammer on ,r4 ,as this bends forward1 it breaks contact at ,b1 the core loses its magnetism and the spring flies back1 to again make contact4 ,this is repeated many times per second4 ,illustration3 ,,fig4 #dd4 ,as a heavy spark occurs at ,b on the break of contact1 the condenser1 ,j1 is attached at ,m ,k4 ,this is a series of insulated tinfoil sheets1 which has the property of nullifying the spark at ,b1 and so preventing the waste of platinum with which both adjustment screw ,a and spring ,r are equipped4 ,a ,ruhmkorff coil differs from a simple primary coil in three main points4 ,two separate coils instead of one2 high insulation1 and a primary coil of few turns4 ,in the simple coil we desired self-induction2 here1 we desire to avoid it as much as possible4 ,the average size ,ruhmkorff coil1 for jump spark work1 would be one giving a #b-;inch spark1 specifications for which are as follows3 ,spool--,nine inches long by one inch in diameter4 ,end cheeks #d inches high by #c inches wide4 ,core--,sufficient soft iron wires1 #i inches long by ,no4 #bb ,b4 ,w4 gauge as will fill the spool tube4 ,primary--,two layers ,no4 #ad ,b4 ,s4 gauge cotton-covered copper wire4 ,secondary--,two and one-half pounds ,no4 #cf ,b4 ,s4 gauge double cotton or silk-covered magnet wire wound in four sections 7or more than four sections1 if feasible74 ,condenser--,seventy sheets tinfoil #d by #g-a_/b inches2 #hj sheets condenser paper #e by #h inches4 ,,spool4 ,this should be made up of a fibre tube #i inches in length by about #a_/af inch thick1 and should be firmly fixed into the spool ends4 ,if it be glued in it should also be pinned as well2 it is easily possible to drive in a few screws passing through the tube into the spool ends1 particularly as the soft iron core1 being of loose wires1 will adapt itself to the slightly projecting screw-heads4 ,remember that this spool must be made strong2 if it comes apart during the winding process1 much trouble will ensue1 and perhaps all the wires lost or ruined4 ,for reasons to be seen later1 do not affix the right-hand spool end yet1 but have it ready4 ,the core consists of as many fine iron wires1 say of ,no4 #bb ,b4 ,w4 gauge1 as can be forced into the tube1 but the core can better be added after the windings are all in2 that is1 in such cases where a rigid spool tube is used4 ,,primary ,,winding4 ,this consists of two layers of ,no4 #ad ,b4 ,s4 gauge cotton 7or silk7 covered copper magnet wire1 and should be evenly and tightly laid on4 ,for winding coils1 a lathe is a most handy machine1 or the spool can be mounted on a spindle and rotated by hand4 ,it is not feasible here to give all details of coil-construction2 reference should be made to the many excellent works on the subject4 ,the two ends are brought out through holes in the spool ends1 as indicated for the simple primary coil before described4 ,after winding1 the wire is to be well basted with melted paraffin wax until it is saturated1 any excess being scraped off so as to leave a smooth cylindrical surface for the secondary coil4 ,half a dozen turns of stout paper or oiled silk is now to be wound on1 and enough paraffin wax added to leave an insulation at least one-quarter of an inch around the outside of the winding4 ,the right-hand end of spool1 where the end was not attached1 will require a little care that the wire does not run off2 but1 as only two layers are to be wound1 it is an easy thing to do4 ,when the primary coil is finished off1 cut three pieces of hard rubber four inches square1 with a central hole just big enough that they may be slipped on over the primary coil to form divisions into which the secondary wire goes4 ,these can be fixed equal distances apart by means of removable wooden blocks1 which are taken off as each section is wound4 ,,secondary ,,coil4 ,the secondary coil consists of about #b-a_/b pounds ,no4 #cf ,b4 ,s4 gauge silk or cotton-covered magnet wire1 wound evenly in layers in the sections on the primary coil4 ,before any wire goes into a section1 it must be seen that the division fits tight to the primary coil4 ,it will be best to pour around the coil some melted paraffin wax so as to form an insulating ring1 and prevent any possibility of the spark creeping under the section division into the next4 ,the actual operation of winding presents no difficulty other than those of keeping the wire from damage and getting as even layers as possible4 ,if each layer is separated from its neighbor by a strip of paraffined paper1 it makes even winding easier1 and better insulation4 ,as to the insulating of the secondary coil1 it can be done in a variety of ways4 ,the coil can be soaked in molten paraffin until saturated1 or the wire can be made to pass through a dish of molten paraffin while on its way from the wire reel to the coil4 ,in the latter case the wire must be guided by means of glass rollers1 as the wax would harden rapidly if touched by the fingers4 ,in connecting up the sections1 the similar ends are to be joined2 that is1 the inside ends to inside ends1 and outside ends to outside ends1 as per diagram 7,fig4 #de74 ,this will bring two outside ends free for attachment to binding posts4 ,fig4 #df shows direction of winding and connecting the two middle coils1 ,a ,c being the inside layers next to primary and ,b ,d the outside layers4 ,illustration3 ,,fig4 #de4 ,an outside coat of paraffin wax is now given to the coil and a wrapping of waxed paper laid on4 ,then1 if desired1 a cover of sheet-rubber or a layer of cloth can be put on over all1 to finish the job4 ,,base1 ,,key1 ,,and ,,condenser4 ,illustration3 ,,fig4 #df4 ,the base for a ,ruhmkorff coil generally resembles an oblong shallow box4 ,the coil is mounted on the lid1 and the condenser inside the box1 the connections being made on the lower side of the lid4 ,it is preferable1 except for appearance' sake1 to make all connections outside the box1 but this is left to the worker's choice4 ,illustration3 ,,fig4 #dg4 ,the ,condenser is made up of #gj sheets of tinfoil each about #d inches by #g-a_/b1 and #hj sheets of clean white paper #e by #h inches placed alternately1 and saturated with paraffin wax4 ,the tinfoil sheets are laid so that about #a_/b inch projects out of the paper sheets at each end1 the alternate sheets coming out at the same end1 and the projecting pieces being bent together gives the effect of a pair of tinfoil sheets insulated from each other1 aggregating the sum of all the small ones4 ,illustration3 ,,fig4 #dh4 ,the coil can now be attached to the base by means of screws passing through the lid into the coil ends4 ,if a vibrating contact breaker be desired1 reference to ,fig4 #dd will show method of connection4 ,fig4 #dg shows details of a contact breaker of similar design4 ,r is hammer head of soft iron1 ,s a spring about thickness of clock spring and #c_/h inch wide or more4 ,b is contact point1 both spring and adjustment screw ,a being fitted with platinum contacts4 ,c is a check nut1 to hold ,a from turning4 ,i is an adjustment to tighten or loosen spring ,s1 by means of a lug which it carries on its shaft4 ,it is well insulated from pillar carrying ,a1 by the hard rubber bushing1 ,i4 ,the condenser is laid in the box under the coil and attached as in ,fig4 #dd2 that is1 one set of sheets to the contact pillar1 and the other set to the adjustment screw4 ,for gas-lighting work1 it is generally preferable to use a contact or strap key 7,fig4 #dh71 instead of a vibrator4 ,the key can be mounted on coil base1 in which case the condenser will be attached in same manner as for the vibrator4 ,,chapter ,,vi4 ,,how ,,to ,,select ,,batteries ,,for ,,gas ,,lighting4 ,before entering into a description of the various batteries used in electric gas lighting1 it will be well to briefly consider a few simple electrical rules bearing upon the subject4 ,a current of electricity has electromotive force1 or difference of potential figured in volts1 and current figured in amperes4 ,for example we will use the water analogy 7,fig4 #di74 ,two tanks1 ,a ,b1 on the same level1 are connected by a pipe ,c4 ,supposing tank ,a be filled with water and the pipe1 ,c1 to be opened2 the water will flow along ,c into ,b until the level in each tank is equal4 ,so long as there is a difference of level1 there will be a pressure in ,c1 owing to the water behind it4 ,replacing the tanks ,a and ,b by unequally electrified bodies1 and the pipe ,c by a conductor of electricity1 the flow of water is represented by the tendency of the electrified bodies to equalize themselves by a flow of current along the conductor1 ,c4 ,to sum up3 ,the difference of level is now difference of potential1 the pounds pressure along the pipe being expressed as electromotive force in volts4 ,illustration3 ,,fig4 #di4 ,the quantity of water flowing along the pipe is measured1 as electricity1 in amperes4 ,as the quantity of water passing in a given time is regulated by the size of the pipe and its own pressure1 so the quantity of electricity is also regulated4 ,a conductor of electricity offers resistance to the flow of current according to its sectional area and the material of which it is composed1 this resistance being expressed in ohms4 ,the greater the voltage and lower the resistance1 the more current4 ,this law1 and its kindred applications1 are expressed as follows3 ,c ,e_/,r4 ,c is current in amperes1 ,e electromotive force in volts1 and ,r resistance in ohms4 ,thus a wire with a resistance of #ej ohms would pass #b amperes with an electromotive force of #ajj volts4 ,to find resistance when other two factors are known1 the formula is ,r ,e_/,c4 ,in selecting a battery for work1 regard must be made to the current required1 and its period of flow4 ,for energizing a gas lighting primary coil1 the current must be large1 but is only required occasionally1 the battery standing idle for long periods4 ,in this case the class called open circuit cells are preferable1 as they contain no strong acids and do not deteriorate to any extent when not in use4 ,of such class is the ,leclanche-,samson1 ,monarch1 carbon cylinder1 and most so-called dry cells4 ,as the resistance in a conductor affects the current flow1 so it does in a battery cell2 the internal resistance of a battery is determined by its size1 proximity of the elements1 etc4 ,cells with small zincs and porous cups are of high internal resistance1 those with large sheet zincs and big carbon surfaces1 of low internal resistance4 ,as the primary coil used in gas lighting is never much over one ohm1 a cell of low internal resistance should be selected4 ,but as the wires leading to the burners must be taken into account1 a number of cells should be used to produce enough electromotive force to overcome the added resistance4 ,now battery cells can be arranged in a variety of ways--in series for higher electromotive force1 and in multiple--for greater current4 ,illustration3 ,,fig4 #ej4 ,fig4 #ej represents the series arrangement2 here the zinc of one cell is connected to the carbon of the next2 this adds the electromotive forces together and thus gives greater ability to overcome resistance1 but it also adds together the resistance of each cell4 ,thus #d cells1 each #b volts and of one-half ohm internal resistance1 would1 in series1 have an ,e4 ,m4 ,f4 of #h volts and an internal resistance of #b ohms1 current #d amperes4 ,fig4 #ea shows four cells in multiple1 the zinc of each cell and the carbons of each cell are connected4 ,here the result would be but #b volts1 but the internal resistance would be only one-quarter1 viz3 one-eighth of an ohm1 current #af amperes4 ,illustration3 ,,fig4 #ea4 ,the readiest rule for connecting a battery is to arrange it according to the resistance of the line or outside wiring4 ,so as we will have to use house-wiring far exceeding in length that on the coil1 and probably of less diameter4 ,therefore the series arrangement will be the one to use1 and not less than four cells of a low-resistance battery4 ,,the ,,leclanche4 ,this battery consists of a carbon rod surrounded by granular peroxide of manganese forming the positive pole and a piece of zinc for the negative pole1 both elements being immersed in a solution of sal ammoniac 7chloride of ammonia74 ,if a wire be run outside the solution and connecting the carbon and zinc1 a current of electricity flows along it4 ,the chemical action taking place is as follows3 ,the zinc combines with the chlorine of the solution1 liberating free hydrogen and ammonia4 ,the hydrogen appears at the carbon1 where it is acted upon by the oxygen of the peroxide of manganese4 ,if too much current is taken from the cell1 that is1 if the wire or circuit be of too low resistance1 the oxidizing action of the peroxide is not rapid enough1 and a film of hydrogen1 which is a poor conductor1 forms over the carbon and increases the resistance of the battery--also setting up what is termed 8local action0 7actually1 a battery opposing a battery74 ,after a rest1 the hydrogen is absorbed1 but a cell rarely regains its pristine activity after too severe demands upon it4 ,the original ,leclanche batteries were imported from ,france1 the home of the inventor1 but of recent years they are made in the ,united ,states1 ,england and ,germany4 ,the most important point to be considered in a galvanic cell is the purity of its active parts4 ,the zincs should be as near chemically pure as can be obtained2 the peroxide of manganese of the best quality and perfectly free from foreign substances1 and the sal ammoniac the purest that can be manufactured4 ,the actual difference in work between a battery so constructed1 and the average cheap cell sold at a price to catch the unwise1 is tremendous4 ,and this difference is indicated1 not only in work1 but when the battery is at rest4 ,local action in a cheap battery will exhaust it even when it is not in circuit1 whereas a battery cell of good material will remain in good order for months without more attention than the addition of water or sal ammoniac4 ,it has been often remarked that the batteries made to-day are inferior to those made years ago1 but it is only true of the cheap-priced cells2 if a good price is paid and attention given to securing a well made cell1 the output will be as satisfactory4 ,illustration3 ,,fig4 #eb4 ,to set up a ,leclanche cell1 proceed as follows3 ,put six ounces of sal ammoniac into the glass jar2 fill the jar one-third full of clear water and stir4 ,put in the porous cup and fill the jar with water up to its neck1 pouring a few teaspoonfuls of water into the hole in porous cup4 ,when the cell is in working condition1 the level of the solution will be found to have receded1 owing to absorption by the porous cup4 ,to prevent the creeping of sal ammoniac up the neck of jar and on to the terminals of the cell1 a layer of paraffin is applied to neck of jar and porous cup4 ,should this need renewing1 vaseline can be used1 or any heavy grease1 care being taken that it does not get on electrodes or where the wires are to be fastened4 ,when the cell refuses to work1 throw out old solution1 wash porous cup1 jar and zinc in warm water1 and replace with new solution4 ,there is a limit1 when a new porous cup must be used1 but this can be done when cell does not work after being treated as above4 ,the electromotive force of the ,leclanche cell is about #a4de1 and current on short circuit of nearly one ampere1 depending of course on thickness and porosity of porous cup1 size of zinc1 and a few other points4 ,,the ,,samson ,,cell4 ,fig4 #ec is one of the ,leclanche group1 in which a compound carbon element displaces the earthenware porous cup4 ,this carbon is composed of two parts1 a hollow-fluted lower piece and a threaded top1 which carries the binding post4 ,in the process of manufacture1 the top piece is heated red-hot and plunged into hot paraffin wax1 thus ensuring a complete diffusion of the paraffin throughout the carbon4 ,in this way the creeping of salt or solution1 and consequent corrosion of electrodes and failure of cell1 are avoided4 ,the lower portion is much more porous than the upper and is filled with a combination of pea-carbon and peroxide of manganese held in by a plug at the bottom4 ,this plug can be removed and new depolarizer added4 ,directions given by the manufacturers for renewing this element are to hold the lower end of the carbon over a burner flame until the plug is softened and can be removed1 or to immerse the extreme lower end of the carbon in boiling water4 ,after refilling1 a cork plug can be used4 ,illustration3 ,,fig4 #ec4 ,the ,e4 ,m4 ,f4 of the ,no4 #b size is from #a4dj to #a4dg volts1 and current1 on short circuit1 of #ab to #af amperes4 ,the ,no4 #b ,special has same ,e4 ,m4 ,f41 but current of only #e amperes1 being intended where strong current is not required but quick recuperation4 ,it will be seen that this cell is far more suited to electric gas-lighting work than the simple ,leclanche1 owing to its great current delivery4 ,,the ,,dry ,,cell4 ,of so-called dry cells there are numbers on the market at so low a price that it does not pay to make one's own4 ,but for those who wish to do so1 the following formula1 furnished by ,mr4 ,wm4 ,roche1 of ,new ,standard battery fame1 will be found excellent3 ,one pint ,,clear ,,water4 ,five ounces sal ammoniac4 ,six ounces zinc chloride4 ,dissolve the sal ammoniac in the water thoroughly4 ,let stand twenty-four hours4 ,then add the zinc chloride1 and when cool1 will be ready for use4 99 99 99 99 99 ,when you have your zinc cup ready1 pour a little wax in the bottom1 to insulate2 place a piece of blotting-paper inside cup and laying tight against the zinc1 about three turns4 ,the negative element is prepared as follows3 ,one pound pure carbon1 powdered2 one pound black oxide manganese2 mix thoroughly4 ,then add sufficient of above solution to hold it together without being plastic1 as that would be too wet to tamp4 ,moisten your paper in the zinc cup thoroughly4 ,place your stick or plate of carbon in centre of zinc cup1 hold it there central while you pack in the carbon manganese element all around it2 be sure that carbon manganese1 or negative element1 does not touch zinc cup4 ,if it does1 your cell will run down quickly4 ,it is a good precaution to have your paper half an inch higher than cup when in the cup1 and soaked with the solution4 ,give it a couple of quick taps on the bench2 that will curl the paper in at the bottom and insure against any internal short circuit4 ,when your cell is filled up1 clean all the carbon element away from the zinc4 ,seal1 and your battery is ready when you've got the connections on4 ,illustration3 ,,fig4 #ed4 ,,the ,,new ,,standard ,,dry ,,cell4 ,the principal sizes of this cell 7,fig4 #ed7 are as follows3 ,no4 #b--e-g_/h #b-g_/af4 ,no4 #c--c-c_/d #a-g_/h4 ,no4 #e--f #b-i_/af4 ,no4 #f--f #c4 ,no4 #g--g #c4 ,the electromotive force is #a4e volts1 current of the ,no4 #g size on short circuit1 #bd amperes4 ,nos4 #b1 #e1 #f1 or #g are most suitable for electric gas lighting1 either by simple primary coil or jump spark coil4 ,,the ,,edison ,,lalande ,,cell4 ,this cell 7,fig4 #ee71 gives a large1 steady current and is of low internal resistance1 but its electromotive force is not high1 being less than 4#g volt on closed circuit4 ,its output of current varies with the size1 type ,s being 4#jbe ohm internal resistance and capacity of #cjj ampere-hours4 ,the ,edison ,lalande cell can be applied to electric gas lighting in cases where a large demand is made upon the battery1 for example in church or theatre lighting4 ,its elements consist of positive plates of amalgamated zinc suspended on each side of negative plates of black oxide of copper4 ,the electrolyte is an aqueous solution of caustic soda4 ,a layer of heavy paraffin oil is poured on top of the solution to prevent the solution from evaporating and also to keep the soda crystals from creeping up and over the rim of the jar4 ,illustration3 ,,fig4 #ee4 ,to set up an ,edison ,lalande cell1 fill the jar up to the brown mark with clear water2 pour in the soda from the tin box1 and stir4 ,when thoroughly dissolved1 pour on top of the solution one half-inch layer of the oil which is sent with the battery4 ,then the elements attached to the cover can be inserted1 and the cell is ready for use4 ,use care not to splash the solution1 as it will burn the clothing and skin4 ,if any does get on1 a little animal grease or vegetable oil will quickly saponify it4 ,in the action of this cell the oxide of copper is reduced to metallic copper and the zincs consumed1 it being intended that each element will require renewal at the same time4 ,upon picking into the oxide plate with a sharp-pointed instrument1 if the plate is red throughout1 it is exhausted2 but1 should it show black in its interior1 it is still capable of a little more use1 but is preferable to use a new plate whenever there is but little oxide left4 ,never remove the oxide plates from the battery1 and do not allow the solution to be less than one inch above oxide plates4 ,,the ,,fuller1 ,,or ,,bichromate ,,cell4 ,although not often necessary in gas-lighting work1 there is at times a demand for a heavy current1 such as in lighting a big building1 where a large coil must be operated4 ,at such times a bichromate of potash cell becomes of service4 ,one of the types is shown in ,fig4 #ef4 ,j is a jar containing electropoion fluid described below4 ,c is a carbon plate immersed in this fluid4 ,p is a porous cup holding the zinc1 ,z1 and being filled with a solution of #ah parts common salt1 #gb parts water1 and one ounce mercury4 ,illustration3 ,,fig4 #ef4 ,the electropoion fluid for the outer jar is made by one pound bichromate of potash or soda to one gallon of water1 mixing in a stone vessel4 ,when dissolved1 add three pounds commercial sulphuric acid carefully1 a little at a time1 and stir the mixture constantly as it gets hot4 ,always add the acid to the mixture2 never attempt to pour the mixture into the acid1 or trouble will result4 ,the sodium salt is preferable to the potassium1 owing to its greater solubility and its not forming chrome alum--a hard precipitate which sticks to jars1 elements1 etc41 to their detriment4 ,illustration3 ,,fig4 #eg4 ,fig4 #eg1 a form of battery known as the ,grenet battery1 is used where there is no porous cup4 ,the zinc element1 ,z1 is mounted on a rod ,r passing through the cap ,g of a glass jar1 ,j1 and can be raised or lowered into the electropoion fluid which the jar contains4 ,this is a good scheme where the battery is liable to stand idle for a long period4 ,,care ,,of ,,open ,,circuit ,,batteries4 ,terminals4--,take care that the solutions do not splash over terminals2 keep all terminals and binding post screws clean and bright4 ,see that all wires are tightly clamped in terminals1 also that their ends are clean4 ,a loose contact is productive of infinite trouble4 ,examine connections that elements are in proper relation to each other4 ,if in multiple1 to produce large current--zincs together and carbons together4 ,if in series1 for high electromotive force--zinc to carbon1 throughout battery4 ,zincs4--,see that the zincs are clean2 if crystals form1 either reduce strength of solution with water1 or scrape zincs clean1 and watch if repeated4 ,examine screw which holds wire2 it often corrodes1 and makes poor contact in the thread4 ,a clever device for preserving a rod zinc from the accumulation of crystals is made by the manufacturers of the ,samson cell4 ,it consists of a thin paper tube which is slipped over the zinc4 ,when the crystals accumulate so as to impair the cell1 the tube is slipped off and a new one put on4 ,this device increases the internal resistance of the cell but very slightly4 ,porous cups and carbons4--,wash in warm water4 ,carbons can be well soaked in warm water and dried in sun1 in a place where they will not accumulate dust4 ,porous cups should be well soaked in warm water1 and left to drain in a place exposed to dustless air4 ,examine binding post holes and screws4 ,solutions4--,do not make too strong4 ,use not more than six ounces1 or more than four ounces avoirdupois1 of chemically pure sal ammoniac to one cell ,leclanche4 ,warm water can be used for making solutions1 if desired4 ,some persons drop a teaspoonful of acetic acid in the cell2 it is not recommended4 ,if in a place where sal ammoniac cannot be procured1 use temporarily common table-salt in same proportion2 thoroughly well clean battery first4 ,batteries should be kept in a cool dry place4 ,dry cells should stand upright1 also in a cool place1 and an examination made once in a while of the connections4 ,,index4 ,,page ,acetylene ,burner #af ,argand ,automatic ,burner #bc ,argand ,burner #ad ,automatic ,burner #ai ,batteries1 open circuit #b ,boston ,cut-,out #ea ,breaks1 to locate #cd ,burner1 ,acetylene #af ,burner1 ,argand #ad ,burner1 ,argand ,automatic #bc ,burner1 ,automatic #ai ,burner1 ,bartholdi #ba ,burners1 choice of #cj ,burner1 ,concealed ,automatic #bd ,burners1 ,connecting #bf ,burners1 ,distribution of #cj ,burner1 ,gasolene #ah ,burner1 ,pendant #g ,burner1 ,ratchet #aj ,burner1 ,ring #bc ,burner1 ,stem #ac ,burner1 ,smith #ef ,burner1 ,vibrator #bc ,burner1 ,welsbach #ae ,choice of ,burners #cj ,clockwork ,cut-,out #eb ,coil1 ,primary #e1 #df ,coil1 ,ruhmkorff #f ,coil1 ,secondary #e ,connections of ,burners #bf ,connections to ground #ch ,contact ,breaker #ge ,cut-,out1 ,boston #ea ,cut-,out1 ,bulb #ed ,cut-,out1 ,clockwork #eb ,cut-,out1 ,syracuse #ej ,danger of ,burners #cj ,defects in ,burners #bi ,diagram of ,wiring #ca ,door-,trip #dc ,edwards' ,burner #fa ,edwards' ,condenser #fj ,edwards' ,system #fb ,finished houses1 wiring of #ch ,fixtures1 wiring of #dj ,frontispiece #ca ,fuller ,battery #id ,galvanometer #c ,gasolene ,burner #ah ,gas-fixture wire #cg ,grenet ,battery #ie ,ground connections #ch ,hall1 ,burners for #cj ,induced ,current #c ,induction1 ,action of #c ,insulator #ei ,jump ,spark ,system #ee ,key ,strap #gf ,lalande ,battery #ib ,leclanche ,battery #hc ,multiple1 ,batteries in #hb ,negative pole #b ,open circuit batteries #b ,pendant ,burner #g1 #i ,positive pole #b ,primary ,coils #df ,push ,button1 to wire #db ,ratchet ,burner #aj ,ring ,burner #bc1 #fc ,ruhmkorff ,coil #f1 #fg ,samson ,battery #hg ,secondary ,coil #e ,section ,switch #cc ,series method #eg ,series1 ,batteries in #hb ,shellac varnish #ch ,smith ,burner #ee ,sparks1 to produce #a ,spool #gj ,standard ,battery #ij ,stem ,burner #ac ,switch1 ,automatic #ff ,switch1 high tension #fd ,switch1 ,section #cc ,syracuse ,cut-,out #ej ,system1 ,edwards' #fb ,trailer #ff ,varnish ,shellac #ch ,vibrator ,burner #bc ,welsbach ,burner #ae ,wimshurst ,machine #a ,winding ,coil #gd ,wire for general use #cf ,wire1 gas-fixture #cg ,wire1 office #cf ,wire1 ,ruhmkorff ,coil #gj ,wiring finished houses #ch ,wiring of ,fixtures #dj ,wiring of ,push ,button #db 99 99 99 99 99 ,new ,standard ,dry ,battery ,all sizes for all systems of ,bells1 ,telephones1 ,burglar ,alarms and ,gas ,lighting4 ,prices according to size and quantity4 ,new ,standard 8,autogas0 ,dry ,battery ,for very heavy work4 ,gas ,mobiles1 ,lights1 etc4 ,no4 #b set1 weight #bg lbs41 neat oak case1 #f4jj per set4 ,new ,standard ,jump ,spark ,rhumkorff ,coils1 #ab4jj each4 ,new ,standard ,flashlight4 ,for use around ,gasolene ,engines1 ,automobiles1 ,launches1 ,clothes ,closets1 etc4 #b4jj each4 ,this light will positively give equal to fifteen hours actual service4 ,a #e4jj article for #b4jj4 ,complete catalogue for the asking4 ,william ,roche1 ,inventor and ,m'f'r1 #db ,vesey ,st41 ,n4 ,y4 ,city ,dealer in ,battery ,materials1 ,chemicals1 ,etc4 ,have a ,look ,into our ,store when in need of anything in the ,electrical line of whatever nature4 ,we deal in everything and carry a good stock4 ,,catalogue ,,on ,electric ,light ,goods1 ,bells1 and ,electric ,house ,goods1 ,switchboards1 c4 ,telephones and ,supplies4 ,j4 ,,jones ,,son1 #fd ,cortlandt ,st41 ,new ,york ,city4 ,,jump ,,spark ,,coils ,x-,ray ,coils4 ,primary ,coils4 ,medical ,coils4 ,telephone ,coils4 ,c4 ,f4 ,,splitdorf1 #ag-bg ,vandewater ,st41 ,n4 ,y4 ,,american ,,books4 ,allen1 ,c4 ,f4 ,railroad ,curves and ,earthwork4 ,a pocketbook for ,surveyors and ,engineers4 ,limp leather1 #b4jj4 ,cordeiro1 ,dr4 ,f4 ,j4 ,b4 ,the ,barometrical ,determination of ,heights1 ,levelling and ,hypssometry4 ,limp leather1 #a4jj4 ,goldingham1 ,a4 ,h4 ,the ,design and ,construction of ,oil ,engines1 with full ,instructions for their ,erecting1 ,testing1 ,running and ,repairing4 #abmo1 cloth1 #b4jj4 ,kinealy1 ,j4 ,h4 ,an ,elementary ,text-,book on ,steam ,engines and ,boilers4 ,third edition1 cloth #b4jj4 ,kinealy1 ,j4 ,h4 ,steam ,heating ,charts for the use of ,architects and ,builders in ,estimating the ,necessary ,heat ,required for ,buildings4 #a4jj4 ,redwood1 ,i4 ,i4 ,lubricants1 ,oils and ,greases4 ,cloth1 #a4ej4 ,we ,mail ,all ,books ,postpaid on ,receipt of ,price4 ,,address3 ,,spon ,,chamberlain1 #ab ,cortlandt ,street1 ,new ,york4 ,,small ,,accumulators ,how ,made and ,used ,a ,practical ,handbook for ,students and ,young ,electricians ,,edited ,,by ,,percival ,,marshall1 ,a4,i4,m4,e4 ,contents of ,chapters ,i4--,the ,theory of the ,accumulator4 ,,ii4--,how to make a #d-,volt ,pocket ,accumulator4 ,,iii4--,how to make a #cb-;,ampere-,hour ,accumulator4 ,,iv4--,types of ,small ,accumulators4 ,v4--,how to ,charge and ,use ,accumulators4 ,,vi4--,applications of ,small ,accumulators1 ,electrical ,novelties1 etc4 ,useful ,receipts4 ,glossary of ,technical ,terms4 #hj pages1 #dj illustrations1 #abmo1 cloth1 #ej;c4 ,,the ,,magneto-,,telephone ,,its ,,construction1 ,fitting ,up and ,adaptability to ,every-,day ,use ,,by ,,norman ,,hughes ,,contents ,,of ,,chapters ,some electrical considerations3 ,i4--,introductory4 ,,ii4--,construction4 ,,iii4--,lines1 ,indoor ,lines4 ,,iv4--,signalling ,apparatus4 ,v4--,batteries4 ,open ,circuit ,batteries4 ,closed ,circuit ,batteries4 ,,vi4--,practical ,operations4 ,circuit with ,magneto ,bells and ,lightning ,arresters4 ,how to ,test the ,line4 ,push-,button ,magneto ,circuit4 ,two ,stations with ,battery ,bells4 ,,vii4--,battery ,telephone4 ,battery ,telephone ,circuit4 ,three ,instruments on one ,line4 ,,viii4--,general remarks4 ,index4 #hj pages1 #bc illustrations1 #abmo1 cloth1 #a4jj4 ,in paper1 #ej;c4 ,,everybody',s ,,book ,,on ,,electricity ,,practical ,,electrics ,a ,,universal ,,handy-,,book ,,on ,,everyday ,,electrical ,,matters ,,fifth ,,edition ,,contents3 ,alarms4--,doors and ,windows2 ,cisterns2 ,low ,water in ,boilers2 ,time ,signals2 ,clocks4 ,batteries4--,making2 ,cells2 ,bichromate2 ,bunsen2 ,callan's2 ,copper-oxide2 ,cruikshank's2 ,daniel's2 ,granule carbon2 ,groves2 ,insulite2 ,leclanch2 ,lime ,chromate2 ,silver ,chloride2 ,smee2 ,thermo-electric4 ,bells4--,annunciator ,system2 ,double ,system2 and ,telephone2 ,making2 ,magnet for2 ,bobbins or ,coils2 ,trembling2 ,single ,stroke2 ,continuous ,ringing4 ,connections4 ,carbons4 ,coils4--,induction2 ,primary2 ,secondary2 ,contact-breakers2 ,resistance4 ,intensity ,coils4--,reel2 ,primary2 ,secondary2 ,core2 ,contact-breaker2 ,condenser2 ,pedestal2 ,commutator2 ,connections4 ,dynamo-electric ,machines4--,field-,magnets2 ,pole-pieces2 ,field-magnet ,coils2 ,armature ,cores and ,coils2 ,commutator ,collectors and ,brushes2 ,relation of size to efficiency2 ,methods of exciting ,field-,magnets2 ,magneto-,dynamos2 ,separately excited ,dynamos2 ,shunt ,dynamos2 ,field-,magnets2 ,armatures2 ,collectors2 ,brush ,dynamo2 ,alternate ,currents4 ,fire ,risks4--,wires2 ,lamps2 ,danger to persons4 ,measuring4--,non-,registering ,instruments2 ,registering ,instruments4 ,microphones4 ,motors4 ,phonographs4 ,photophones4 ,storage4 ,telephones4--,forms2 ,circuits and ,calls2 ,transmitter and ,switch2 ,switch for ,simplex2 etc41 etc4 #ace ,,pages4 #abf ,,illustrations4 #h,,vo4 ,cloth1 #ge cents ,,sample ,,copies ,,mailed ,,to ,,any ,,address ,,on ,,receipt ,,of #h ,,cents4 ,illustration3 ,,the ,,model ,,engineer ,,amateur ,,electrician ,a ,,journal ,,of ,,mechanics ,,and ,,electricity ,,for ,,amateurs ,,and ,,students ,,edited ,,by ,,percival ,,marshall ,,its ,,good ,,points4 ,better than any paper of its kind ever published4 ,the articles are original and practical4 ,the articles are so clearly and simply written and everything made so plain that it will be found easy to follow the directions and duplicate the articles described4 ,special articles on ,model engines and boilers for yachts1 torpedo-boats and war-ships4 ,designing and building of model yachts and boats4 ,making small tools for model work4 ,the building of small gas engines4 ,building screw-cutting and turning lathes4 ,building all kinds of model stationary and locomotive steam engines and boilers4 ,model engineers and their work4 ,building of all kinds of electrical machines1 apparatus1 coils1 batteries1 telephones1 microphones1 phonographs1 novelties4 ,the articles are fully illustrated1 principally with detail drawings to scale4 ,new ,books1 ,notes and ,queries1 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,spectrum analysis4 #g4 ,currents in vacuo4 #h4 ,rotating effects4 #i4 ,the application of coils to gas lighting4 #aj4 ,batteries for coils4 #aa4 ,secondary ,batteries4 #ab4 ,tesla and ,hertz effects4 #ac4 ,x-,rays and radiography4 #ad4 ,wireless telegraphy4 ,contents4 ,index4 #bij pages1 #gi ,illus4 #e #f-a_/b in4 ,,cloth1 #a4jj ,manual of ,instruction in ,hard ,soldering ,,with ,,an ,,appendix ,,on ,,the ,repair of ,bicycle ,frames ,notes on ,alloys and a ,chapter on ,soft ,soldering ,,by ,,harvey ,,rowell ,the flame1 lamp1 charcoal1 mats1 blow-pipes1 wash-bottle1 binding wire1 chemicals1 borax1 spelter1 silver solder1 gold solder1 oxidation of metals1 fluxes1 anti-oxidisers1 oxidation of cases1 the cone1 oxidising flame1 reducing flame1 heat transmission1 conduction1 capacity of metals1 radiation1 application1 the work table1 the joint1 applying solder1 applying heat1 the use of the blow-pipe1 joints1 making a ferrule1 to repair a spoon1 to repair a watch case1 hard soldering with a forge or hearth1 hard soldering with tongs1 preserving thin edges1 silversmith's pickle1 restoring color to gold1 chromic acid1 to mend steel springs1 sweating metals together1 retaining work in position1 making joints1 applying heat1 preventing the loss of heat1 effect of sulphur lead and zinc1 to preserve precious stones1 annealing and hardening1 burnt iron1 to hard solder after soft solder4 ,tables of--specific gravity1 tenacity1 fusibility1 alloys4 #ff pages1 illustrated1 cloth1 #ge cents4 ,for ,soldering ,receipts1 ,cements and ,lutes1 ,pastes1 ,glues and such like1 see ,,workshop ,,receipts4 ,,new ,,edition 8,,de ,,luxe0 ,,on ,,heavy ,,plate ,,paper ,illustration3 ,a ,,system ,,of ,,easy ,,lettering ,,by ,j4 ,h4 ,,cromwell4 ,,its ,,good ,,points4 ,very easy to learn4 ,a rapid method to become a good letterer with a little practice4 ,very easy to lay out a line of words in ,,strict ,,proportion1 whether it be on a fence #ejj yards long or on a drawing only a few inches across4 ,good for draughtsmen who prefer neat lettering1 yet something out of the ordinary4 ,it contains #bf pages of alphabets whose modifications are almost limitless4 ,one of the cheapest in the market4 ,this little book will be appreciated by draughtsmen who wish to use plain letters 7and yet somewhat different from the ordinary run of letters7 for the titles on drawings4 ,the book will also be valuable and useful to any one who has had no practice in lettering1 as the easy method given for forming the letters will enable a person to form the letters correctly1 and with a little practice to do so quickly4--,american ,machinist4 ,oblong1 #hvo1 cloth1 #ej cents ,workshop ,receipts4 ,,the ,,most ,,complete ,technical ,cyclopedia in #e ,vols4 ,first ,series4 ,principal ,contents4--,bronzes1 ,cements1 ,dyeing1 ,electro-metallurgy1 ,enamels1 ,etchings1 ,fireworks1 ,fluxes1 ,fulminates1 ,gilding1 ,gums1 ,japanning1 ,lacquers1 ,marble ,working1 ,nitro-,glycerine1 ,photography1 ,pottery1 ,varnishes1 #dbj pages1 #ajc illus41 cloth1 #b4jj4 ,second ,series4 ,principal ,contents4--,acidimetry1 ,albumen ,alcohol1 ,alkaloids1 ,bitters1 ,bleaching1 ,boiler ,incrustations1 ,cleansing1 ,confectionery1 ,copying1 ,disinfectants1 ,essences1 ,extracts1 ,fire-proofing1 ,glycerine1 ,gut1 ,iodine1 ,ivory ,substitutes1 ,leather ,matches ,pigments1 ,paint1 ,paper1 ,parchment4 #dhe pages1 #af illus41 cloth1 #b4jj4 ,third ,series4 ,principal ,contents4--,alloys1 ,aluminium1 ,antimony1 ,copper1 ,electrics1 ,enamels1 ,glass1 ,gold1 ,iron1 ,steel1 ,liquors ,lead1 ,lubricants1 ,magnesium1 ,manganese1 ,mercury1 ,mica1 ,nickel1 ,platinum1 ,silver1 ,slag1 ,tin1 ,uranium1 ,zinc4 #dhj pages1 #ahc illus41 cloth1 #b4jj4 ,fourth ,series4 ,principal ,contents4--,waterproofing1 ,packing1 ,stowing1 ,embalming1 ,preserving1 ,leather ,polishes1 ,cooling ,air and ,water1 ,pumps and ,siphons1 ,dessicating1 ,distilling1 ,emulsifying1 ,evaporating1 ,filtering1 ,percolating1 ,macerating1 ,electrotyping1 ,stereotyping1 ,book-binding1 ,straw-plaiting1 ,musical ,instruments1 ,clock and ,watch ,mending1 ,photography #ddc pages1 #bdc illus41 cloth4 #b4jj4 ,fifth ,series4 ,principal ,contents4--,diamond ,cutting1 ,laboratory ,apparatus1 ,filtering1 ,magic ,lanterns ,metal ,work1 ,percolation1 ,illuminating ,agents1 ,tobacco ,pipes1 ,taps1 ,tying and ,splicing ,tackle1 ,repairing ,books1 ,netting1 ,walking ,sticks1 ,boat-,building4 #ddj pages1 #cgc illus41 cloth1 #b4jj4 ,,each ,,series has its own ,contents and ,index and is complete in itself4 ,the ,best and ,cheapest in the ,market ,,algebra ,,self-,,taught ,,for ,,the ,,use ,,of ,mechanics1 ,young ,engineers and ,home ,students ,,by ,w4 ,,paget ,,higgs1 ,m4,a41 ,d4,sc4 ,,fourth ,,edition ,,contents ,symbols and the signs of operation4 ,the equation and the unknown quantity4 ,positive and negative quantities4 ,multiplication1 involution1 exponents1 negative exponents1 roots1 and the use of exponents as logarithms4 ,logarithms4 ,tables of logarithms and proportional parts4 ,transportation of systems of logarithms4 ,common uses of common logarithms4 ,compound multiplication and the binomial theorem4 ,division1 fractions and ratio4 ,rules for division4 ,rules for fractions4 ,continued proportion1 the series and the summation of the series4 ,examples4 ,geometrical means4 ,limit of series4 ,equations4 ,appendix4 ,index4 #ajd pages1 #abmo1 cloth1 #fj;c4 99 99 99 99 99 ,see also ,algebraic ,signs1 ,spons' ,dictionary of ,engineering1 ,no4 #b4 #dj cts4 ,see also ,calculus1 ,supplement to ,spons' ,dictionary1 ,no4 #e4 #ge cts4 ,,cross ,,section ,,paper4 ,,the ,,handy ,,sketching ,,pad4 ,printed on one side1 in blue ink1 all the lines being of equal thickness1 with useful tables4 ,size #h #aj inches4 ,price1 #be;c4 each4 ,per dozen pads1 #b4ej4 ,,the ,,handy ,,sketching ,,book4 ,made from this paper but printed on both sides4 ,size of book #e #h inches1 stiff board covers4 ,price1 #be;c4 each2 per dozen books1 #b4ej4 ,,scale ,,eight ,,to ,,one ,,inch4 ,a large sheet with heavy inch lines and half inch lines1 printed in blue ink4 ,size of sheet1 #ag #bb inches4 ,per quire 7#bd sheets71 #ge;c4 ,,scale ,,ten ,,to ,,one ,,inch4 ,size #ag #bb inches1 printed in blue ink1 with heavy inch lines and half inch lines4 ,per quire 7#bd sheets71 #ge;c4 ,,the ,,electrician',s ,,sketching ,,pad4 ,size #h #aj4 ,scale #aj to #a in4 ,price #be;c4 each4 ,per dozen1 #b4ej4 ,,the ,,electrician',s ,,sketching ,,book4 ,made from this paper4 ,scale #aj to #a inch4 ,size of book #e #h inches1 with stiff board covers4 ,price1 #be;c4 each2 per dozen1 #b4ej4 ,any quantity mailed to any part of the world on receipt of price4 ,or ,books and ,pads ,assorted1 per dozen1 #b4ej4 ,this paper is not ruled4 ,try it and you will find it ,,good1 ,,accurate ,,and ,,cheap4 ,,spon ,,chamberlain1 #ab ,cortlandt ,st41 ,,new ,,york4 ,,practical ,,handbook ,,on ,gas ,engines ,with ,instructions for ,care and ,working of the ,same4 ,,by ,g4 ,,lieckfeld1 ,c4,e4 ,translated with permission of the ,author by ,,george ,,richmond1 ,m4,e4 ,,with ,a ,,chapter ,,on ,,oil ,,engines ,,contents ,choosing and installing a gas engine4 ,the construction of good gas engines4 ,examination as to workmanship1 running1 economy4 ,reliability and durability of gas engines4 ,proper erection of a gas engine4 ,foundation4 ,arrangement for gas pipes4 ,rubber bag4 ,locking devices4 ,exhaust pipes4 ,air pipes4 ,setting up gas engines4 ,brakes and their use in ascertaining the power of gas engines4 ,arrangement of a brake test4 ,distribution of heat in a gas engine4 ,attendance on gas engines4 ,general remarks4 ,gas engine oil4 ,cylinder lubricators4 ,rules as to starting and stopping a gas engine4 ,the cleaning of a gas engine4 ,general observations and specific examination for defects4 ,the engine refuses to work4 ,non-starting of the engine4 ,too much pressure on the gas4 ,water in the exhaust pot4 ,difficulty in starting the engine4 ,irregular running4 ,loss of power4 ,weak gas mixtures4 ,late ignition4 ,cracks in air inlet4 ,back firing4 ,knocking and pounding inside of engine4 ,dangers and precautionary measure in handling gas engines4 ,precautions when opening gas valves1 removing piston from cylinder1 examining with light openings of gas engines4 ,dangers in starting1 cleaning1 putting on belts4 ,oil ,engines4 ,gas engines with producer gas4 ,gasoline and oil engines4 ,concluding remarks4 #abj pages1 illustrated1 l#bmo1 cloth1 #a4jj4 ,,the ,,fireman',s ,,guide ,a ,handbook on the ,care of ,boilers ,,by ,,karl ,p4 ,,dahlstrom1 ,m4,e4 ,,contents ,,of ,,chapters ,i4 ,firing and ,economy of ,fuel4--,precautions before and after starting the fire1 care of the fire1 proper firing1 draft1 smoke1 progress of firing1 fuel on the grate1 cleaning out1 cleaning grate bars and ash pan1 dampers1 firing into two or more furnaces1 dry fuel1 loss of heat4 ,,ii4 ,feed and ,water ,line4--,feeding1 the water line1 false water line1 defective feeding apparatus1 formation of scale1 gauge cocks1 glass gauge1 the float1 safety plug1 alarm whistle4 ,,iii4 ,low ,water and ,foaming or ,priming4--,precautions when water is low1 foaming1 priming4 ,,iv4 ,steam ,pressure4--,steam gauge1 safety valves4 ,v4 ,cleaning and ,blowing ,out4--,cleaning the boiler1 to examine the state of the boiler1 blowing out1 refilling the boiler4 ,,vi4 ,general ,directions4--,how to prevent accidents1 repairs1 the care of the boiler when not in use1 testing boilers1 trimming and cleaning outside4 ,summary of rules4 ,index4 #hvo1 cloth1 #ej cents4 ,,how ,,to ,,run ,engines and ,boilers ,practical ,instruction for ,young ,engineers and ,steam ,users4 ,,by ,,egbert ,,pomeroy ,,watson ,,revised ,,and ,,enlarged ,synopsis of ,contents ,cleaning the boiler1 removing scale1 scale preventers1 oil in boilers1 braces and stays1 mud drums and feed pipes1 boiler fittings1 grate bars and tubes1 bridge walls1 the slide valve1 throttling engine1 the piston1 testing the slide valve with relation to the ports1 defects of the slide valve1 lap and lead1 the pressure on a slide valve1 stem connections to the valve1 valves off their seats1 valve stem guides1 governors1 running with the sun1 eccentrics and connections1 the crank pin1 brass boxes1 bearings on pins1 adjustment of bearings1 the valve and gearing1 setting eccentrics1 the actual operation1 return crank motion1 pounding1 the connections1 lining up engines1 making joints1 condensing engines1 ,torricelli's vacuum1 proof of atmospheric pressure1 pumps1 no power in a vacuum1 supporting a water column by the atmosphere1 starting a new plant1 the highest qualities demanded4 ,water tube boilers1 fire tube boilers1 why water tube boilers steam rapidly1 torpedo boat boilers1 management of water tube boilers1 economy and maintenance of water tube boilers4 #aej pages1 illustrated1 #afmo1 cloth1 #a4jj4 ,,the ,,corliss ,,engine4 ,,by ,,john ,t4 ,,henthorn4 --,,and-- ,,management ,,of ,,the ,,corliss ,,engine4 ,,by ,,charles ,d4 ,,thurber4 ,uniform in ,one ,volume4 ,cloth ,cover2 ,price1 #a4jj4 ,table of ,contents4 ,,chapter ,i4--,introductory and ,historical2 ,steam ,jacketing4 ,,chapter ,,ii4--,indicator ,cards4 ,,chapter ,,iii4--,indicator ,cards continued2 the ,governor4 ,,chapter ,,iv4--,valve ,gear and ,eccentric2 ,valve ,setting4 ,,chapter ,v4--,valve ,setting continued1 with diagrams of same2 ,table for laps of ,steam ,valve4 ,,chapter ,,vi4--,valve ,setting continued4 ,,chapter ,,vii4--,lubrication with diagrams for same4 ,,chapter ,,viii4--,discussion of the ,air ,pump and its ,management4 ,,chapter ,,ix4--,care of ,main ,driving ,gears2 best ,lubricator for same4 ,,chapter ,x4--,heating of ,mills by ,exhaust ,steam4 ,,chapter ,,xi4--,engine ,foundations2 diagrams and templets for same4 ,,chapter ,,xii4--,foundations continued2 ,materials for same1 etc4 ,third ,edition1 with an ,appendix4 ,,the ,,slide ,,valve ,,simply ,,explained ,,by ,w4 ,j4 ,,tennant1 ,,asso4 ,m4,i4,m4,e4 ,,revised ,,and ,,much ,,enlarged ,,by ,j4 ,h4 ,,kinealy1 ,d4,e4 ,,contents ,,of ,,chapters3 ,i4 ,the ,simple ,slide4 ,,ii4 ,the ,eccentric a ,crank4 ,special ,model to ,give ,quantitative ,results4 ,,iii4 ,advance of the ,eccentric4 ,,iv4 ,dead ,centre4 ,order of ,cranks4 ,cushioning and ,lead4 ,v4 ,expansion--,inside and ,outside ,lap and ,lead2 ,advance ,affected ,thereby4 ,compression4 ,,vi4 ,double-,ported and ,piston ,valves4 ,,vii4 ,the ,effect of ,alterations to ,valve and ,eccentric4 ,,viii4 ,note on ,link ,motions4 ,,ix4 ,note on ,very ,early ,cut-,off1 and on ,reversing ,gears in ,general4 #hh ,pages4 #da ,illustrations4 #abmo1 ,cloth1 #a4jj4 ,,quick ,,and ,,easy ,,methods ,,of ,,calculating ,,with ,,the ,,slide ,,rule ,a ,,simple ,,explanation ,,of ,,the ,,theory ,,and ,,use ,,of ,,the ,,slide ,,rule1 ,,logarithms1 ,,etc4 ,with numerous examples worked out4 ,,by ,r4 ,g4 ,,blaine1 ,m4,e4 ,a most reliable1 practical and valuable work for the engineer4 #add ,pages4 ,illustrated4 #abmo1 ,cloth1 #a4jj ,,theoretical ,,and ,,practical ,ammonia ,refrigeration ,a ,work of ,reference for ,engineers and others ,employed in the ,management of ,ice and ,refrigeration ,machinery4 ,by ,,iltyd ,i4 ,,redwood ,,contents ,b4 ,t4 ,u4 ,mechanical ,equivalent of a ,unit of ,heat4 ,specific ,heat4 ,latent ,heat4 ,theory of ,refrigeration4 ,freezing1 by ,compressed ,air4 ,ammonia4 ,characteristics of ,ammonia4 ,the ,compressor4 ,stuffing-,boxes4 ,lubrication4 ,suction and ,discharge ,valves4 ,separator4 ,condenser-,worm1 ,receiver4 ,refrigerator or ,brine ,tank4 ,size of ,pipe and ,area of ,cooling ,surface4 ,charging the ,plant with ,ammonia4 ,jacket-,water1 for ,compressor1 for ,separator4 ,quantity of ,condensing ,water ,necessary4 ,loss due to ,heating of ,condensed ,ammonia4 ,cause of ,variation in ,excess ,pressure4 ,use of ,condensing ,pressure in ,determining ,loss of ,ammonia by ,leakage4 ,cooling ,directly by ,ammonia4 ,freezing ,point of ,brine4 ,making ,brine4 ,specific ,heat of ,brine4 ,regulation of ,brine ,temperature4 ,indirect ,effect of ,condensing ,water on ,brine ,temperature4 ,directions for ,determining ,refrigerating ,efficiency4 ,equivalent of a ,ton of ,ice4 ,compressor ,measurement of ,ammonia ,circulated4 ,loss of ,well-,jacketed ,compressors4 ,loss in ,double-,acting ,compressors4 ,distribution of ,mercury ,wells4 ,examination of ,working ,parts4 ,indicator ,diagrams4 ,ammonia ,figures--,effectual ,displacement4 ,volume of ,gas4 ,ammonia ,circulated per ,twenty-,four ,hours4 ,refrigerating ,efficiency4 ,brine ,figures--,gallons ,circulated4 ,pounds ,circulated4 ,degrees ,cooled4 ,total ,degrees ,extracted4 ,loss due to ,heating of ,ammonia ,gas4 ,loss due to ,heating of ,liquid ,ammonia4 ,calculation of the ,maximum ,capacity of a ,machine4 ,preparation of ,anhydrous ,ammonia4 ,construction of ,apparatus1 etc41 etc4 #aej pages1 #ae illustrations1 cloth1 #a4jj4 ,,spons' #b4ej ,,mechanic',s ,,own ,,book1 ,a ,,practical ,,manual4 ,,principal ,,contents4 ,mechanical ,drawing4 7#ac pages74 ,casting and ,founding4 7#ca pages74 ,forging and ,finishing4 7#ef pages47 ,soldering4 7#bf pages74 ,sheet-,metal ,working4 7#aj pages74 ,carpentry1 ,woods1 ,tools1 etc4 7#bbd pages74 ,cabinet ,making4 7#cf pages74 ,carving and ,fretwork4 7#ac pages74 ,upholstery4 7#f pages74 ,painting1 ,graining and ,marbling4 7#bh pages74 ,staining1 and ,gilding4 7#af pages74 ,polishing1 ,varnishing4 7#bf pages74 ,mechanical ,movements4 7#ef pages74 ,turning and ,lathe work4 7#cj pages74 ,masonry1 ,stonework1 ,brickwork1 ,concrete1 etc4 7#de pages74 ,plastering1 ,whitewashing1 ,paperhanging4 7#ac pages7 ,roofing1 ,glazing4 7#ad pages74 ,bell hanging1 ,gas fitting4 7#h pages74 ,lighting1 ,ventilation1 ,warming4 7#ba pages74 ,foundations1 ,roads and ,bridges1 ,banks1 ,hedges1 ,ditches and ,drains1 ,water ,supply and ,sanitation4 ,house ,construction1 etc4 ,size of book #f-c_/d in4 by #h-c_/d4 #gjb pages1 half extra gilt and #adbj illustrations4