,illustration ,,scientific ,,american ,,supplement ,,no4 #ebj ,,new ,,york1 ,,december #ai1 #ahhe ,scientific ,american ,supplement4 ,vol4 ,vol4 ,,xx1 ,no4 #ebj4 ,scientific ,american established #ahde ,scientific ,american ,supplement1 #e a year4 ,scientific ,american and ,supplement1 #g a year4 99 99 99 99 99 ,,table ,,of ,,contents4 ,i4 ,,engineering1 ,,etc4--,steel ,structures4--,best use of different grades of steel4--,from a paper by ,mr4 ,,jas4 ,,christie4 ,natural ,gas ,fuel and its ,application to ,manufacturing3 ,purposes4--,paper read before the ,iron and ,steel ,institute by ,mr4 ,,andrew ,,carnegie4--,first use of the gas4--,wells near ,pittsburg4--,extent of territory underlain with gas4--,cost of piping4--,analyses ofnatural gas4 ,a ,gas ,engine ,water ,supply ,alarm4--#a figure4 ,the ,water ,supply of ,ancient ,roman ,cities4--,an address by ,prof4 ,w4,h4 ,,corfield4--,aqueducts for the supply of ,borne4--,the aqueduct bridge ,pont du ,gard4--,the supply of ,lyons4--,construction of underground aqueducts4 ,steam ,engine ,economy4--,by ,chief ,engineer ,j4 ,,lowe1 ,u4,s4,n4--,with diagram4 ,the ,elastic ,limit in ,metals4--,selection of wire for suspension bridges1 etc4 ,prices of ,metals in #ahgd and #ahhd4--,with table4 ,,ii4 ,,technology4--,a ,method of ,measuring the ,absolute ,sensitiveness of ,photographic ,dry ,plates4--,by ,wm4 ,h4 ,,pickering4--,from the proceedings of the ,academy of ,arts and ,sciences4 ,soldering and ,repairing ,platinum ,vessels in the ,laboratory4--,by ,j4,w4 ,,pratt4 ,the ,helicoidal or ,wire ,stone ,saw invented by ,m4,p4 ,,gay4--,with engraving of quarry showing application of saw1 and #e figures4 ,portable ,prospecting ,drill and ,automatic ,safety ,gear shown at the ,inventions ,exhibition4--,with #b engravings4 ,,iii4 ,,electricity1 ,,etc4--,electricity in ,warfare4--,by ,lieutenant ,b4,a4 ,,fiske1 ,u4,s4,n4--,electrical torpedoes4--,torpedo detecter4--,military telegraphy and telephony4--,electricity for firing great guns4--,arrangement of wires for lights4--,the search light4--,incandescent lamps for sight signaling4--,electrical launches4--,an electric sight4 ,meucci's ,claims to the ,telephone4--,with description of his instrument and #aj figures4 ,an ,electric ,centrifugal ,machine for ,laboratories4--,by ,,alex4 ,,watt4--,from paper read before the ,british ,association4--#a figure4 ,transmission of ,power by ,electricity4--,experiments of ,m4 ,,marcel ,,deprez4 ,,iv4 ,,art ,,and ,,architecture4--,quadriga for the ,new ,house of ,parliament at ,vienna4--,an engraving4 ,glazed ,ware ,finial4--,with engraving4 ,hotel de ,ville1 ,st4 ,quentin4--,with engraving4 ,fire ,doors in ,mills4--,from a lecture before the ,franklin ,institute by ,c4,j4 ,,hexamer4 ,v4 ,,natural ,,history1 ,,etc4--,preservation of ,insects4 ,an ,accomplished ,parrot4 ,the ,roscoff ,zoological ,laboratory4--,the buildings and rooms4--,the aquarium4--,course of study4 ,the ,murn at the ,berlin ,aquarium4--,with engraving4 ,metamorphosis of ,arctic ,insects4 ,,vi4 ,,medicine4 ,,etc4--,a ,year's ,scientific ,progress in ,nervous and ,mental ,diseases4--,by ,prof4 ,l4,a4 ,,merriam4--,report to the ,nebraska ,state ,medical ,society4 ,scaring the ,baby ,out4 ,,vii4 ,,miscellaneous4--,wage ,earners and their ,houses4--,manufacturers as landlords4--,experiments of ,pullman1 ,owen1 ,peabody1 and others4 ,the ,locked and ,corded ,box ,trick1 with ,directions for making the ,box4--,by ,d ,b4 ,,adamson4--#i figures4 ,a ,perpetual ,calendar4--,with engraving4 99 99 99 99 99 ,,preservation ,,of ,,insects4 ,to remove the verdigris which forms upon the pins1 the pinned insects should be immersed in benzine and left there for a time2 several hours is generally long enough4 ,the administration of this bath cannot be too highly recommended for beetles which have been rendered unrecognizable by grease1 especially when dust has been mixed with the grease4 ,this immersion1 of variable duration according to circumstances1 will restore to these insects1 however bad they have become1 all their brilliancy and all their first freshness1 and the efflorescences of cupric oxide will not reappear4 ,this preventive and curative method is also readily applicable to beetles glued upon paper which have become greasy2 plunge them into benzine in the same way1 and as the gum is insoluble in the liquid1 they remain fastened to their supports4 ,pruinose beetles1 which are few in number1 are the only ones that benzine can alter2 the others1 which are glabrous1 pubescent1 or scaly1 can only gain by the process1 and they will always make a good show in the collection4--,a4 ,dubois in ,feuille des jeunes naturatistes1 ,march1 #ahhe1 p4 #ga4--,psyche4 99 99 99 99 99 ,,quadriga ,,for ,,the ,,new ,,house ,,of ,,parliament1 ,,at ,,vienna4 ,illustration3 ,,quadriga ,,for ,,the ,,new ,,house ,,of ,,parliament1 ,,at ,,vienna4 ,the new ,house of ,parliament at ,vienna is known as one of the finest specimens of pure ,greek architecture erected in this century2 and throughout the entire building great pains have been taken to ornament the same as elaborately as is consistent with good taste4 ,the main buildings are provided with corner pavilions1 the atticas of which project over the roofs1 and these atticas and other parts of the buildings are to be surmounted by quadrigas1 one of which is shown in the annexed cut1 taken from the ,illustrirte ,zeitung4 ,this group was modeled by ,v4 ,pilz1 of ,vienna1 and represents a winged goddess in a chariot drawn by four spirited steeds harnessed abreast4 ,she holds a wreath in her raised right hand1 and her left hand is represented as holding the lines for guiding the horses4 ,the group is full of expression and life1 and will add greatly to the beauty of the building to be surmounted by it4 99 99 99 99 99 ,the strongest wood in the ,united ,states1 according to ,professor ,sargent1 is that of the nutmeg hickory of the ,arkansas region1 and the weakest the ,west ,indian birch 7,rur seva74 ,the most elastic is the tamarack1 the white or shellbark hickory standing far below it4 ,the least elastic and the lowest in specific gravity is the wood of the ,ficus aurea4 ,the highest specific gravity1 upon which in general depends value as fuel1 is attained by the bluewood of ,texas 7,condalia obovata74 99 99 99 99 99 ,,glazed ,,ware ,,finial4 ,illustration3 ,,glazed ,,ware ,,finial4 ,this grand #afth century finial is a fine example of ,french ceramic ware1 or glazed terracotta1 and it is illustrated both by geometrical elevation and a cross sectional drawing4 ,this latter shows the clever building up of the structure by means of a series of five pieces1 overlapping each other1 and kept rigid by means of a stout wrought-iron upright in the center1 bolted on to the ridge1 and strapped down on the hip pieces4 ,its outline is well designed for effect when seen at a distance or from below1 and its glazed surface heightens the artistic colorings1 giving it a brilliant character in the sunlight1 as well as protecting the ware from the action of smoke and weather4--,build4 ,news4 99 99 99 99 99 ,,wage ,,earners ,,and ,,their ,,houses4 ,,manufacturers ,,as ,,landlords4 ,among the more prominent movements of the day for the improvement of the condition of the working men are those which are growing into fashion with large manufacturing incorporations4 ,their promise lies immediately in the fact that they call for no new convictions of political economy1 and hence have nothing disturbing or revolutionary about them4 ,accepting the usages and economical principles of industrial life1 as the progress of business has developed them1 an increasing number of large manufacturers have deemed it to their interest not only to furnish shops and machinery for their operatives1 but dwellings as well1 and in some instances the equipments of village life1 such as schools1 chapels1 libraries1 lecture and concert halls1 and a regime of morals and sanitation4 ,probably the most expensive investment of this sort in the ,united ,states1 if not in the world1 by any single company1 is that of ,pullman1 on ,lake ,calumet1 a few miles south of ,chicago1 an enterprise as yet scarcely five years old4 ,it is by no means a novel undertaking1 except in the magnitude1 thoroughness1 and unity of the scheme4 ,twenty years ago the managers of the ,lonsdale ,mills1 in ,rhode ,island1 were erecting cottages on a uniform plan and maintaining schools and religious services for their operatives4 ,more recent but more extensive is the village of the ,ponemah ,cotton ,mill1 near ,taftville1 ,conn4 ,these are illustrations merely of similar investments upon a smaller scale elsewhere4 ,but the ,european examples are older1 such as ,robert ,owen's experiment at ,new ,lanark in ,scotland1 ,saltaire in ,yorkshire1 ,dollfuss' ,mulhausen ,quarter in ,alsace1 and ,m4 ,godin's community in the ,french village of ,guise1 which are among the more familiar instances of investments originally made on business principles1 with a view to the improved conditions of workmen4 ,new ,lanark failed as a commercial community through the visionary character of its founder2 the ,godin works at ,guise have passed into the co-operative phase within the past five years1 but ,saltaire and ,mulhausen still retain their proprietary business features4 ,the class of ventures of which these instances are but the more conspicuous examples has peculiar characteristics4 ,they differ from the ,peabody and ,waterlow buildings of ,london1 described in ,bradstreet's last ,august1 from ,starr's ,philadelphia dwellings1 and from the operations of the ,improved ,dwellings ,association of ,new ,york in these particulars3 the latter are financially a pure question of direct investment2 are mainly concerned with life among the poor of cities1 and1 whatever philanthropy may be in their motive1 are capable of adaptation to any class of citizens4 ,the former1 while investments also1 are composite1 the business of manufacturing being associated with that of rent collecting and sharing its profits and losses2 their field of operations is almost invariably rural1 and tenancy is restricted to the employes of the proprietor4 ,on the other hand1 they differ from all co-operative and socialistic communities in that they are an adaptation to existing circumstances1 propose to demonstrate no new theories of economics1 are free from all religious bonds1 do not depend on any unity of opinion1 and do not touch the question of the proper distribution of wealth4 ,it is1 of course1 no new thing for owners of large factories1 particularly in country districts1 to furnish tenements for their operatives1 and oftentimes it is quite indispensable that they should1 because there would otherwise be no accommodation for their workmen4 ,what is recent and exceptional is the spread of the belief that it pays to make the accommodations furnished healthful1 convenient1 and attractive4 ,the sources of profit from this careful provision are these3 the proprietors have control of the territory1 and are able to prescribe regulations which keep out the saloon and disreputable characters1 and at once there is a saving in police and court and poor taxes2 for the same reason the workmen are more regular and steady in their labor1 for there is no ,st4 ,monday holiday1 nor confused head and uncertain hand2 the tenants are better able to pay their rents1 and when their landlord and employer are the same person1 he collects his rent out of the wages2 the superior accommodations and more settled employment act strongly against labor strikes4 ,it will be seen that the larger and better product of labor is a great factor in the profitableness of such enterprises1 and that it arises from the improved character of the laborer1 on the same principle that a farmer's stock pays him best when it is of good breed1 is warmly housed1 and well fed4 ,against the operations of the ,london ,peabody and ,waterlow funds it has been alleged that they dispossess the poor shiftless tenant and bring in a new class1 so that they do not improve the condition of their tenants1 but afford opportunity for better ones to cheapen the price of their accommodations4 ,the manufacturing landlord cannot wholly do this1 because the first thing he has to consider is whether the applicant for a dwelling is a good workman1 not whether he can be trusted for his rent4 ,his labor he must have4 ,his outlook is to make that labor worth more to him1 by placing it in the best attainable surroundings4 ,can this be done8 ,if so1 the ends of humanity are answered as well as the purse filled1 for both interests correspond4 ,mr4 ,pullman1 who founded the enterprise on ,calumet ,lake1 has uttered sentiments like these1 and has proved that in this instance it does pay to make his workmen's families comfortable1 and secure from sickness and temptation4 ,as a financial operation ,pullman is profitable4 ,there are now #a1gjj dwellings1 either separate or in apartment houses1 in this town1 where five years ago the prairie stretched on every side unbroken4 ,every tenement is connected with common sewerage1 water1 and gas systems1 in which the most scientific principles and expert skill have been applied4 ,the price of tenements ranges from #e per month for two rooms in an apartment house to #af for a separate dwelling of five rooms2 but there is a different class of houses for clerks1 superintendents1 and overseers4 ,the average price per room is #c4cj a month1 or nearly twelve per cent4 higher than in ,massachusetts manufacturing towns1 where it is #b4hf4 ,taking each tenement at an average of three rooms1 this rate will pay six per cent4 on an investment of #c1adj1jjj1 without taking into account taxes and repairs1 or say six per cent4 on #c1jjj1jjj4 ,but one source of profit of great moment must not be overlooked1 and it is the appreciation of real estate by the increase of population4 ,this is a small factor in a great city1 at least so far as concerns the humbler grade of dwellings1 but in the country it is enormous4 ,a tract of land which has been a farm becomes a village of from #a1jjj to #aj1jjj inhabitants4 ,its value advances by leaps and bounds4 ,at ,pullman1 in addition to the shops and dwellings1 there are trees and turf-bordered malls and squares1 a church1 a theater1 a free library with reading rooms1 a public hall1 a market house1 provided at the expense of the company4 ,liquor can only be sold at the hotel to its guests1 and then under restrictions4 ,there is a system of public schools under a board of education1 which is about the only civic organization1 strictly speaking1 in the community4 ,one man suffices for police duty1 and he made but fifteen arrests in the last two years4 ,it is reported that the death rate so far1 including the mortality from accidents1 has been under seven in #a1jjj per annum4 ,in ,great ,britain the rate is a small fraction over #bb in #a1jjj4 ,the vital statistics of the ,united ,states show a smaller mortality than this1 but they are rendered abnormal by the heavy immigration which pours into the country4 ,emigrants are1 in the language of insurance men1 a selected class4 ,they are usually at the most vigorous time of life and of hardiest and most enterprising spirit4 ,they leave behind them the very young and the old and those enfeebled by disease or habits4 ,to this cause must be attributed in part the exceptional record of ,pullman in death rate1 as it is a new town4 ,yet there can be no question that the sanitary conditions of the place are excellent4 ,it is difficult in mixed enterprises of this nature to tell what the rate of profit upon the tenement part of the business is1 since the rental and the factory react upon each other2 but in the ,american instances quoted in this article the investment as a whole is remunerative4 ,in the ,godin operations at ,guise1 which have been co-operative for the last five years1 the capital is put at #a1cbj1jjj1 and the net earnings have averaged during that time #bjd1fdj per annum1 or #ae per cent4 ,at ,pullman a demand has arisen on the part of the tenants for a chance to acquire proprietorship in their homes2 and while the company has withheld the privilege from its original purchase of #c1ejj acres1 it has bought adjoining land1 where it offers to advance money for building1 and to take pay in monthly installments4 ,this assimilates so much of the enterprise to that at ,mulhausen1 and shows the drift toward a co-operative phase of capital and labor4 ,indeed1 this tendency will probably prove to be strongly characteristic of all similar schemes as fast as they attain to any magnitude4 ,tendencies which can be resisted in communities of few hundreds become overpowering when the population rises into thousands4 ,but from the purely commercial point of view1 this drift is hardly to be deprecated1 so long as the operation of selling houses returns the capital and interest safely4 ,projects of this nature go far toward modifying the stress of antagonisms between labor and capital1 because if they are successful these are harmonized to an appreciable extent1 and this gives public interest to them4 ,the eventual adjustment must come1 not from convictions of duty1 doctrinaire opinions1 or sentiments of sympathy1 but on business principles1 and it is a sure step in advance to show that self-interest and philanthropy are in accord4 ,how great the field for experiments of this nature is in the ,united ,spates may be gathered from the census of #ahhj1 which shows #b1gah1hje persons employed in the industrial establishments of the country1 with an annual production of #e1hdb1jjj1jjj1 and a capital of nearly half that amount4 ,of these hands and values nearly two-thirds belong to the north ,atlantic ,states1--,bradstreet's4 99 99 99 99 99 ,,hotel ,,de ,,ville1 ,,st4 ,,quentin4 ,this charming building has an uncommonly well-designed facade1 picturesque in the extreme1 rich in detail1 and thoroughly dignified4 ,we are indebted to ,m4 ,levy1 of ,paris1 for the loan of ,m4 ,garen's spirited etching1 from which our illustration is taken4 ,the arcaded piazza on the ground story1 the niche-spaced tier of traceried windows on the first floor1 the flamboyant paneled cornice stage1 and the three crowning gables over it unite in one harmonious conception1 the whole elevation being finished by a central tower1 while at either end of the facade two massively treated buttresses furnish a satisfactory inclosing line1 and give more than a suggestion of massiveness1 so necessary to render an arcaded front like this quite complete within itself2 otherwise it must more or less appear to be only part of a larger building4 ,the style is ,late ,gothic1 designed when the first influence of the ,early ,renaissance was beginning to be felt through ,france as well as ,belgium1 and in several respects the design has a ,flemish character about it4 ,illustration3 ,,hotel ,,de ,,ville1 ,,st4 ,,quentin4 ,st4 ,quentin is situated on the ,goy1 in the department of ,cotes du ,nord1 and the town is seated in a picturesque valley some ten miles ,s4,s4,w4 of the capital1 ,st ,brieuc1 which is a bishop's see1 and has a small harbor near the ,english ,channel1 and about thirty miles from ,st4 ,malo4--,building ,news4 99 99 99 99 99 ,,fire ,,doors ,,in ,,mills4 ,footnote3 ,from a lecture before the ,franklin ,institute by ,c4 ,john ,hexamer4 ,there are few parts in fire construction which are of so much importance1 and generally so little understood1 as fire doors4 ,instances of the faulty construction of these1 even by good builders and architects1 may daily be seen4 ,iron doors over wooden sills1 with the flooring boards extending through from one building to the other1 are common occurrences4 ,we frequently find otherwise good doors hung on wooden jambs by ordinary screws4 ,sliding doors are frequently hung on to woodwork1 and all attachments are frequently so arranged that they would be in a very short time destroyed by fire1 and cause the door to fall4 ,in case of fire1 a solid iron door offers no resistance to warping4 ,in an iron lined door1 on the contrary1 the tendency of the sheet iron to warp is resisted by the interior wood1 and when this burns into charcoal1 it still resists all warping tendencies4 ,i have seen heavily braced solid iron doors warped and turned after a fire1 having proved themselves utterly worthless4 ,it is needless to say that when wooden doors are lined1 they should be lined on both sides2 but frequently we find so-called fireproof doors lined on one side only4 ,good doors are frequently blocked up with stock and other material1 so that in case of fire they could not be closed without great exertion2 or they have been allowed to get out of order1 so that in case of fire they are useless4 ,this has been so common that it has given rise to the jocular expression of insurance men1 when they are told that a fire door exists between the two buildings1 ,warranted to be open in case of fire4 ,the strictest regulations should exist in regard to closing the fire doors nightly4 ,frequently we find that although the fire door1 and its different parts1 are correctly made1 there are openings in the wall which would allow the fire to travel from one building to the other1 such as unprotected belt and shaft holes4 ,that a fire door may be effective1 it must be hung to the only opening in the wall4 ,the greatest care must be exercised to keep joists from extending too far into the wall1 so as not to touch the joists of the adjacent building1 which would transmit the flames from one building to the other in case of fire4 ,a good stone sill should be placed under the door1 and the floor thereby entirely cut4 ,sills should be raised about one and a half inches above the level of the floor1 in order to accomplish the necessary flooding of the same4 ,if stock must be wheeled from one building to the other1 the sill can be readily beveled on both sides of the wall1 allowing the wheels to pass readily over it4 ,lintels should consist of good brick arches4 ,when swing doors are used1 they should be hung on good iron staples1 well walled into the masonry1 and the staples so arranged that the door will have a tendency to close by its own weight4 ,the door should consist of two layers of good one and a quarter inch boards1 nailed crosswise1 well nailed together and braced1 and then covered with sheet iron nailed on1 or if of sheet tin1 flanged1 soldered1 and nailed4 ,particular care should be taken to insert plenty of nails1 not only along the edge of the door1 but crosswise in all directions4 ,i have seen cases1 where the entire covering had been ripped off through the warping tendencies of the sheet iron4 ,the hinges on these doors should be good strap hinges1 tightly fastened to the door by bolts extending through it1 and secured by nuts on the other side4 ,good latches which keep the door in position when closed should always be provided4 ,in no case should the door be provided with a spring lock which cannot be freely opened1 as employes might thereby be confined in a burning room4 ,sliding doors should be hung on wrought iron runways1 fastened tightly to the wall4 ,wooden runways iron lined1 which we frequently see1 are not good1 as the charring of the wood in the interior causes them to weaken and the doors to drop4 ,runways should be on an incline1 so that the door when not held open will close itself4 ,care must be taken to have a stop provided in the runway1 so that the doors may not1 as ,i have frequently seen them1 overrun the opening which it is to protect4 ,doors should overlap the edges of the openings on all sides4 ,large projecting jambs should never be used4 ,all doors contained in fire walls should have springs or weights attached to them1 so as to be at all times closed4 ,fire doors can be shut automatically by a weight1 which is released by the melting of a piece of very fusible solder employed for this purpose4 ,so sensitive is this solder that a fire door has been made to shut by holding a lamp some distance beneath the soldered link and holding an open handkerchief between the lamp and link4 ,though the handkerchief was not charred1 hot air enough had reached the metal to fuse the solder and allow the apparatus to start into operation4 ,these solders are alloys more fusible than the most fusible of their component metals4 ,a few of them are3 ,wood's alloy1 consisting of3 cadmium1 #a to #b parts2 tin1 #b parts2 lead1 #d parts2 bismuth1 #g to #h parts4 ,this alloy is fusible between #aej and #aei ,fahr4 ,the fusible metal of ,d',arcet is composed of3 bismuth1 #h parts2 lead1 #e parts2 tin1 #c parts4 ,it melts at #agc4c4 ,we can1 therefore1 by proper mixture1 form a solder which will melt at any desirable temperature4 ,numerous devices for closing doors automatically have been constructed1 all depending upon the use of the fusible solder catch4 99 99 99 99 99 ,,steel ,,structures4 ,at a recent meeting of the ,engineers' ,club of ,philadelphia1 ,mr4 ,james ,christie presented a paper upon ,the ,adaptation of ,steel to ,structural ,work4 ,the price of steel has now fallen so low1 as compared with iron1 that its increased use will be actively stimulated as the building industries revive4 ,the grades and properties of the steels are so distinct and various that opinions differ much as to the adaptability of each grade for a special purpose4 ,hitherto1 engineers have favored open hearth steel on account of uniformity1 but recent results obtained from ,bessemer steel tend to place either make on equality4 ,the seeming tendency is to specify what the physical properties shall be1 and not how the steel shall be made4 ,for boiler and ship plates1 the mildest and most ductile steel is favored4 ,for ships' frames and beams1 a harder steel1 up to #ge1jjj pounds tenacity1 is frequently used4 ,for tension members of bridges1 steel of #fe1jjj to #ge1jjj pounds tenacity is usually specified2 and for compression members1 #hj1jjj to #ij1jjj pounds4 ,in the ,forth ,bridge1 compression steel is limited to #ge1jjj to #hb1jjj pounds4 ,such a marked advantage occurs from the use of high tension steel in compression members1 and the danger of sudden failure of a properly made strut is so little1 that future practice will favor the use of hard steel in compression1 unless the material should prove untrustworthy4 ,in columns1 even as long as forty diameters1 steel of #ij1jjj pounds tenacity will exceed the mildest steel #ce per cent41 or iron #ej per cent41 in compressive resistance4 ,the present uncertainty consists largely as to how high-tension steel will endure the manipulation usual with iron without injury4 ,a few experiments were recently made by the writer on riveted struts of both mild and hard steel1 which had been punched1 straightened1 and riveted1 as usual with iron1 but no indication of deterioration was found4 ,steel castings are now made entirely trustworthy for tensile working stresses of #aj1jjj to #ae1jjj pounds per square inch4 ,in some portable machinery1 an intermittent tensile stress is applied of #ae1jjj pounds1 sometimes rising to #bj1jjj pounds per square inch of section1 without any evidence of weakness4 99 99 99 99 99 ,equal volumes of amyl alcohol 7rectified fusel oil7 and pure concentrated hydrochloric acid1 shaken together in a test tube1 unite to form a single colorless liquid2 if one volume of benzine 7from petroleum7 be added to this1 and the tube well shaken1 the contents will soon separate into three distinct colorless fluids1 the planes of demarkation being clearly discernible by transmitted light4 ,drop into the tube a particle of acid magenta2 after again shaking the liquids together1 the lower two zones will present different shades of red1 while the supernatant hydrocarbon will remain without color4 99 99 99 99 99 ,a ,,method ,,of ,,measuring ,,the ,,absolute ,,sensitiveness ,,of ,,photographic ,,dry ,,plates4 ,footnote3 ,from the ,proceedings of the ,academy of ,arts and ,sciences4--,amer4 ,jour4 ,by ,,william ,h4 ,,pickering4 ,within the last few years the subject of dry plate photography has ,increased very rapidly1 not only in general popularity1 but also in importance in regard to its applications to other departments of science4 ,numerous plate manufacturers have sprung up in this country as well as abroad1 and each naturally claims all the good qualities for his own plates4 ,it therefore seemed desirable that some tests should be made which would determine definitely the validity of these claims1 and that they should be made in such a manner that other persons using instruments similarly constructed would be able to obtain the same results4 ,perhaps the most important tests needed are in regard to the sensitiveness of the plates4 ,most plate makers use the wet plates as their standard1 giving the sensitiveness of the dry plates at from two to sixty times greater2 but as wet plates vary quite as much as dry ones1 depending on the collodion1 condition of the bath1 etc41 this system is very unsatisfactory4 ,another method1 employed largely in ,england1 depends on the use of the ,warnerke sensitometer4 ,in this instrument the light from a tablet coated with luminous paint just after being exposed to a magnesium light is permitted to shine through a colored transparent film of graduated density upon the plate to be tested4 ,each degree on the film has a number1 and1 after a given exposure1 the last number photographed on the plate represents the sensitiveness on an empirical scale4 ,there are two or three objections to this instrument4 ,in the first place1 the light-giving power of the luminous tablet is liable to variations1 and1 if left in a warm1 moist place1 it rapidly deteriorates4 ,again1 it has been shown by ,captain ,abney that plates sensitized by iodides1 bromides1 and chlorides1 which may be equally sensitive to white light1 are not equally affected by the light emitted by the paint2 the bromides being the most rapidly darkened1 the chlorides next1 and the iodides least of all4 ,the instrument is therefore applicable only to testing plates sensitized with the same salts4 ,in this investigation it was first shown that the plates most sensitive for one colored light were not necessarily the most so for light of another color4 ,therefore it was evident that the sun must be used as the ultimate source of light1 and it was concluded to employ the light reflected from the sky near the zenith as the direct source4 ,but as this would vary in brilliancy from day to day1 it was necessary to use some method which would avoid the employment of an absolute standard of light4 ,it is evident that we may escape the use of this troublesome standard1 if we can obtain some material which has a perfectly uniform sensitiveness2 for we may then state the sensitiveness of our plates in terms of this substance1 regardless of the brilliancy of our source4 ,the first material tried was white filter paper1 salted and sensitized in a standard solution of silver nitrate4 ,this was afterward replaced by powdered silver chloride1 chemically pure1 which was found to be much more sensitive than that made from the commercial chemicals4 ,this powder is spread out in a thin layer1 in a long paper cell1 on a strip of glass4 ,the cell measures one centimeter broad by ten in length4 ,over this is laid a sheet of tissue paper1 and above that a narrow strip of black paper1 so arranged so as to cover the chloride for its full length and half its breadth4 ,these two pieces of paper are pasted on to the under side of a narrow strip of glass which is placed on top of the paper cell4 ,the apparatus in which the exposures are made consists of a box a little over a meter in length1 closed at the top by a board1 in which is a circular aperture #ae'h cm4 in diameter4 ,over this board may be placed a cover1 in the center of which is a hole #j4je cm4 in diameter1 which therefore lets through #j4jjjja as much light as the full aperture4 ,the silver chloride is placed a distance of just one meter from the larger aperture1 and over it is placed the photographic scale1 which might be made of tinted gelatines1 or1 as in the present case1 constructed of long strips of tissue paper1 of varying widths1 and arranged like a flight of steps2 so that the light passing through one side of the scale traverses nine strips of paper1 while that through the other side traverses only one strip4 ,each strip cuts off about one-sixth of the light passing through it1 so that1 taking the middle strip as unity1 the strips on either side taken in order will transmit approximately-- #a #b #c #d #e #f #g #h #i #b4j #a4fe #a4d #a4b #a4j #j4he #j4g #j4f #j4e ,the instrument is now pointed toward the zenith for about eight minutes1 on a day when there is a bright blue sky4 ,on taking the apparatus into the dark room and viewing the impression by gaslight1 it will be found that the markings1 which are quite clear at one end1 have entirely faded out by the time the middle division is reached4 ,the last division clearly marked is noted4 ,five strips cut from sensitized glass plates1 ten centimeters long and two and a half in width1 are now placed side by side under the scale1 in the place of the chloride4 ,by this means we can test1 if we wish1 five different kinds of plates at once4 ,the cover of the sensitometer containing the #j4je;cm4 hole is put on1 and the plates exposed to sky light for a time varying anywhere between twenty seconds and three minutes1 depending on the sensitiveness of the plates4 ,the instrument is then removed to the dark room1 and the plates developed by immersing them all at once in a solution consisting of four parts potassium oxalate and one part ferrous sulphate4 ,after ten minutes they are removed1 fixed1 and dried4 ,their readings are then noted1 and compared with those obtained with the silver chloride4 ,the chloride experiment is again performed as soon as the plates have been removed1 and the first result confirmed4 ,with some plates it is necessary to make two or three trials before the right exposure can be found2 but if the image disappears anywhere between the second and eighth divisions1 a satisfactory result may be obtained4 ,the plates were also tested using gaslight instead of daylight4 ,in this case an ,argand burner was employed burning five cubic feet of gas per hour4 ,a diaphragm #a cm4 in diameter was placed close to the glass chimney1 and the chloride was placed at #aj cm4 distance1 and exposed to the light coming from the brightest part of the flame1 for ten hours4 ,this produced an impression as far as the third division of the scale4 ,the plates were exposed in the sensitometer as usual1 except that it was found convenient in several cases to use a larger stop1 measuring #j4caf cm4 in diameter4 ,the following table gives the absolute sensitiveness of several of the best known kinds of ,american and foreign plates1 when developed with oxalate1 in terms of pure silver chloride taken as a standard4 ,as the numbers would be very large1 however1 if the chloride were taken as a unit1 it was thought better to give them in even hundred thousands4 ,,sensitiveness ,,of ,,plates4 ,plates4 ,daylight4 ,gaslight4 ,carbutt transparency #j4g 44 ,allen and ,rowell #a4c #aej ,richardson standard #a4c #aj ,marshall and ,blair #b4g #adj ,blair instantaneous #c4j #adj ,carbutt special #d4j #bj ,monroe #d4j #be ,wratten and ,wainwright #d4j #aj ,eastman special #e4c #cj ,richardson instantaneous #e4c #bj ,walker ,reid and ,inglis #aa4j #fjj ,edwards #aa4j #bj ,monckhoven #af4j #abj ,beebe #af4j #bj ,cramer #af4j #abj ,it will be noted that the plates most sensitive to gaslight are by no means necessarily the most sensitive to daylight2 in several instances1 in fact1 the reverse seems to be true4 ,it should be said that the above figures cannot be considered final until each plate has been tested separately with its own developer1 as this would undoubtedly have some influence on the final result4 ,meanwhile1 two or three interesting investigations naturally suggest themselves2 to determine1 for instance1 the relative actinism of blue sky1 haze1 and clouds2 also1 the relative exposures proper to give at different hours of the day1 at different seasons of the year1 and in different countries4 ,a somewhat prolonged research would indicate what effect the presence of sunspots had on solar radiation--whether it was increased or diminished4 99 99 99 99 99 ,,natural ,,gas ,,fuel ,,and ,,its ,,application ,,to ,,manufacturing ,,purposes4 ,footnote3 ,read before the ,iron and ,steel ,institute of ,london1 ,may #h1 #ahhe4 ,by ,mr4 ,,andrew ,,carnegie1 ,new ,york4 ,in these days of depression in manufacturing1 the world over1 it is specially cheering to be able to dwell upon something of a pleasant character4 ,listen1 therefore1 while ,i tell you about the natural gas fuel which we have recently discovered in the ,pittsburg district4 ,that ,pittsburg should have been still further favored in the matter of fuel seems rather unfair1 for she has long been noted for the cheapest fuel in the world4 ,the actual cost of coal1 to such as mine their own1 has been between #ds4 and #es4 per ton2 while slack1 which has always been very largely used for making gas in ,siemens furnaces and under boilers1 has ranged from #bs4 to #bs4 #f;d4 per ton4 ,some mills situated near the mines or upon the rivers for many years received slack coal at a cost not exceeding #as4 #f;d4 per ton4 ,it is this cheap fuel which natural gas has come to supplant4 ,it is now many years since the pumping engines at oil wells were first run by gas1 obtained in small quantities from many of the holes which failed to yield oil4 ,in several cases immense gas wells were found near the oil district2 but some years elapsed before there occurred to any one the idea of piping it to the nearest manufacturing establishments1 which were those about ,pittsburg4 ,several years ago the product of several gas wells in the ,butler region was piped to two mills at ,sharpsburg1 five miles from the city of ,pittsburg1 and there used as fuel1 but not with such triumphant success as to attract much attention to the experiment4 ,failures of supply1 faults in the tubing1 and imperfect appliances for use at the mills combined to make the new fuel troublesome4 ,seven years ago a company drilled for oil at ,murraysville1 about eighteen miles from ,pittsburg4 ,a depth of #a1cbj feet had been reached when the drills were thrown high in the air1 and the derrick broken to pieces and scattered around by a tremendous explosion of gas4 ,the roar of escaping gas was heard in ,munroville1 five miles distant4 ,after four pipes1 each two inches in diameter1 had been laid from the mouth of the well and the flow directed through them1 the gas was ignited1 and the whole district for miles round was lighted up4 ,this valuable fuel1 although within nine miles of our steel-rail mills at ,pittsburg1 was permitted to waste for five years4 ,it may well be asked why we did not at once secure the property and utilize this fuel2 but the business of conducting it to the mills and there using it was not well understood until recently4 ,besides this1 the cost of a line was then more than double what it is now2 we then estimated that #adj1jjj would be required to introduce the new fuel4 ,the cost to-day does not exceed #a1ejj per mile4 ,as our coal was not costing us more than #cs4 per ton of finished rails1 the inducement was not in our opinion great enough to justify the expenditure of so much capital and taking the risk of failure of the supply4 ,two years ago men who had more knowledge of the oil-wells than ourselves had sufficient faith in the continuity of the gas supply to offer to furnish us with gas for a sum per year equal to that hitherto annually paid for coal until the amount expended by them on piping had been repaid1 and afterward at half that sum4 ,it took us about eighteen months to recoup the gas company1 and we are now working under the permanent arrangement of one-half the previous cost of fuel on cars at work4 ,since our success in the use of this new natural fuel at the rail mills1 parties still bolder have invested in lines of piping to the city of ,pittsburg1 fifteen to eighteen miles from the wells4 ,the territory underlain with this natural gas has not yet been clearly defined4 ,at the principal field1 that of ,murraysville 7from which most of the gas is obtained to-day71 ,i found1 upon my visit to that interesting region last autumn1 that nine wells had been sunk1 and were yielding gas in large quantities4 ,one of these was estimated as yielding #cj1jjj1jjj cubic feet in #bd hours4 ,this district lies to the northeast of ,pittsburg1 running southward from it toward the ,pennsylvania ,railroad4 ,gas has been found upon a belt averaging about half a mile in width for a distance of between four and five miles4 ,beyond that again we reach a point where salt water flows into the wells and drowns the gas4 ,several wells have been bored upon this belt near the ,pennsylvania ,railroad1 and have been found useless from this cause4 ,geologists tell us that in this region a depression of #fjj feet occurs in the strata1 but how far the fault extends has not yet been ascertained4 ,wells will no doubt soon be sunk southward of the ,pennsylvania ,railroad upon this half-mile belt4 ,swinging round toward the southwest1 and about twenty miles from the city1 we reach the gas fields of ,washington county4 ,the wells so far struck do not appear to be as strong as those of the ,murraysville district1 but it is possible that wells equally productive may be found there hereafter4 ,there are now four wells yielding gas in the district1 and others are being drilled4 ,passing still further to the west1 we reach another gas territory1 from which manufacturing works in ,beaver ,falls and ,rochester1 some twenty-eight miles west of ,pittsburg1 receive their supply4 ,proceeding with the circle we are drawing in imagination around ,pittsburg1 we pass from the west to the southwest without finding gas in any considerable quantity1 until we reach the ,butler gas field1 equidistant from ,pittsburg on the northwest1 with ,washington county wells on the southwest4 ,proceeding now from the ,butler field to the ,allegheny ,river1 we reach the ,tarentum district1 still about twenty miles from ,pittsburg1 which is supplying a considerable portion of the gas used4 ,drawing thus a circle around ,pittsburg1 with a radius of fifteen to twenty miles1 we find four distinct gas-producing districts4 ,in the city of ,pittsburg itself several wells have been bored2 but the fault before mentioned seems to extend toward the center of the circle1 as salt water has rushed in and rendered these wells wholly unproductive1 though gas was found in all of them4 ,i spent a few days very pleasantly last autumn driving with some friends to the two principal fields1 the ,murraysville and the ,washington county4 ,in the former district the gas rushes with such velocity through a #f-;inch pipe1 extending perhaps #bj feet above the surface1 that it does not ignite within #f feet of the mouth of the pipe4 ,looking up into the clear blue sky1 you see before you a dancing golden fiend1 without visible connection with the earth1 swayed by the wind into fantastic shapes1 and whirling in every direction4 ,as the gas from the well strikes the center of the flame and passes partly through it1 the lower part of the mass curls inward1 giving rise to the most beautiful effects gathered into graceful folds at the bottom--a veritable pillar of fire4 ,there is not a particle of smoke from it4 ,the gas from the wells at ,washington was allowed to escape through pipes which lay upon the ground4 ,looking down from the roadside upon the first well we saw in the valley1 there appeared to be an immense circus-ring1 the verdure having been burnt and the earth baked by the flame4 ,the ring was quite round1 as the wind had driven the flame in one direction after another1 and the effect of the great golden flame lying prone upon the earth1 swaying and swirling with the wind in every direction1 was most startling4 ,the great beast ,apollyon1 minus the smoke1 seemed to have come forth from his lair again4 ,the cost of piping is now estimated1 at the present extremely low prices1 with right of way1 at #a1fjj sterling per mile1 so that the cost of a line to ,pittsburg may be said to be about #bg1jjj sterling4 ,the cost of drilling is about #a1jjj1 and the mode of procedure is as follows3 ,a derrick being first erected1 a #f inch wrought-iron pipe is driven down through the soft earth till rock is reached from #ge to #ajj feet4 ,large drills1 weighing from #c1jjj to #d1jjj lb41 are now brought into use2 these rise and fall with a stroke of #d to #e feet4 ,the fuel to run these drills is conveyed by small pipes from adjoining wells4 ,an #h-;inch hole having been bored to a depth of about #ejj feet1 a #e-e_/h inch wrought-iron pipe is put down to shut off the water4 ,the hole is then continued #f inches in diameter until gas is struck1 when a #d-;inch pipe is put down4 ,from forty to sixty days are consumed in sinking the well and striking gas4 ,the largest well known is estimated to yield about #cj1jjj1jjj cubic feet of gas in twenty-four hours1 but half of this may be considered as the product of a good well4 ,the pressure of gas as it issues from the mouth of the well is nearly or quite #bjj lb4 per square inch4 ,one of the gauges which ,i examined showed a pressure of #ahg lb4 ,even at works where we use the gas nine miles from the well1 the pressure is #ge lb4 per square inch4 ,at one of the wells1 where it was desirable to have a supply of pure water1 ,i found a small engine worked by the direct pressure of the gas as it came from the well2 and an excellent supply of water was thus obtained from a spring in the valley4 ,eleven lines of pipe now convey gas from the various wells to the manufacturing establishments in and around ,pittsburg4 ,the largest of these for the latter part of the distance is #ab inches in diameter4 ,several are of #h inches throughout4 ,the lines originally laid are #f inches in diameter4 ,many of the mills have as yet no appliances for using the gas1 and much of it is still wasted4 ,it is estimated that the iron and steel mills of the city proper require fuel equal to #aff1jjj bushels of coal per day2 and though it is only two years since gas was first used in ,pittsburg1 it has already displaced about #dj1jjj bushels of coal per day in these mills4 ,sixty odd glass works1 which required about #bj1jjj bushels of coal per day1 mostly now use the natural gas4 ,in the work around ,pittsburg beyond the city limits1 the amount of coal superseded by gas is about equal to that displaced in the city4 ,the estimated number of men whose labor will be dispensed with in ,pittsburg when gas is generally used is #e1jjj4 ,it is only a question of a few months when all the manufacturing carried on in the district will be operated with the new fuel4 ,as will be seen from the analyses appended to this paper1 it is a much purer fuel than coal2 and this is a quality which has proved of great advantage in the manufacture of steel1 glass1 and several other products4 ,with the exception of one1 and perhaps two concerns1 no effort has been made to economize in the use of the new fuel4 ,in our ,union ,iron ,mills we have attached to each puddling furnace a small regenerative appliance1 by the aid of which we save a large percentage of fuel4 ,the gas companies will no doubt soon require manufacturers to adopt some such appliance4 ,at present1 owing to the fact that there is a large surplus constantly going to waste1 they allow the gas to be used to any extent desired4 ,contracts are now made to supply houses with gas for all purposes at a cost equal to that of the coal bill for the preceding year4 ,in the residences of several of our partners no fuel other than this gas is now used1 and everybody who has applied it to domestic purposes is delighted with the change from the smoky and dirty bituminous coal4 ,some1 indeed1 go so far as to say that if the gas were three times as costly as the old fuel1 they could not be induced to go back to the latter4 ,it is therefore quite within the region of probability that the city1 now so black that even ,sheffield must be considered clean in comparison1 may be so revolutionized as to be the cleanest manufacturing center in the world4 ,a walk through our rolling mills would surprise the members of the ,institute4 ,in the steel rail mills for instance1 where before would have been seen thirty stokers stripped to the waist1 firing boilers which require a supply of about #djj tons of coal in twenty-four hours--ninety firemen in all being employed1 each working eight hours--they would now find one man walking around the boiler house1 simply watching the water gauges1 etc4 ,not a particle of smoke would be seen4 ,in the iron mills the puddlers have whitewashed the coal bunkers belonging to their furnaces4 ,i need not here say how much pleasure it will afford me to arrange that any fellow members of the ,institute who may visit the republic are afforded an opportunity to see for themselves this latest and most interesting development of the fuel question4 ,good ,mother ,earth supplies us with all the fuel we can use and more1 and only asks us to lead it under our boilers and into our heating and puddling furnaces1 and apply the match4 ,during the winter several explosions have occurred in ,pittsburg1 owing to the escape of gas from pipes improperly laid4 ,the frost having penetrated the earth for several feet and prevented escape upward1 the freed gas found its way into the cellars of houses1 and1 as it is odorless1 its presence was not detected4 ,this resulted in several alarming explosions2 but the danger is to be remedied before next year4 ,lower pressure will be carried in the pipes through the city1 and escape pipes leading to the surface will be placed along the surface at frequent intervals4 ,in the case of manufacturing establishments1 the gas is led into the mills overhead1 and1 all the pipes being in the open air1 no danger of explosion is incurred4 ,the following extract from the report of a committee1 made to the ,american ,society of ,mechanical ,engineers at a recent meeting1 gives an idea of the value of the new fuel3 ,natural gas1 next to hydrogen1 is the most powerful of the gaseous fuels1 and1 if properly applied1 one of the most economical1 as very nearly its theoretical heating power can be utilized in evaporating water4 ,being so free from all deleterious elements1 notably sulphur1 it makes better iron1 steel1 and glass than coal fuel4 ,it makes steam more regularly1 as there is no opening of doors1 and no blank spaces are left on the grate bars to let cold air in1 and1 when properly arranged1 regulates the steam pressure1 leaving the man in charge nothing to do but to look after the water1 and even that could be accomplished if one cared to trust to such a volatile water-tender4 ,boilers will last longer1 and there will be fewer explosions from unequal expansion and contraction1 due from cold draughts of air being let in on hot plates4 ,an experiment was made to ascertain the value of gas as a fuel in comparison with coal in generating steam1 using a retort or boiler of #db inches diameter1 #aj feet long1 with #d inch tubes4 ,it was first fired with selected ,youghiogheny coal1 broken to about #d inch cubes1 and the furnace was charged in a manner to obtain the best results possible with the stack that was attached to the boiler4 ,nine pounds of water evaporated to the pound of coal consumed was the best result obtained4 ,the water was measured by two meters1 one in the suction and the other in the discharge4 ,the water was fed into a heater at a temperature of from #fj to #fb2 the heater was placed in the flue leading from the boiler to the stack in both gas and coal experiments4 ,in making the calculations1 the standard #gf lb4 bushel of the ,pittsburg district was used4 ,six hundred and eighty-four pounds of water were evaporated per bushel1 which was #fj4i per cent4 of the theoretical value of the coal4 ,where gas was burned under the same boiler1 but with a different furnace1 and taking #a lb4 of gas to be #b4ce cubic feet1 the water evaporated was found to be #bj4ca lb41 or #hc4d per cent4 of the theoretical heat units were utilized4 ,the steam was under the atmospheric pressure1 there being a large enough opening to prevent any back pressure1 the combustion of both gas and coal was not hurried4 ,it was found that the lower row of tubes could be plugged and the same amount of water could be evaporated with the coal2 but with gas1 by closing all the tubes--on the end next the stack--except enough to get rid of the products of combustion1 when the pressure on the walls of the furnace was three ounces1 and the fire forced to its best1 it was found that very nearly the same results could be obtained4 ,hence it was concluded that the most of the work was done on the shell of the boiler4 ,in no other way can ,i give the members of the ,iron and ,steel ,institute so much information in regard to this new fuel as by including in this paper a very able communication from the chief chemist at our ,edgar ,thomson ,steel ,works1 ,mr4 ,s4,a4 ,ford1 who is to-day the highest authority upon the subject3 ,so much has been claimed for natural gas as regards the superiority of its heating properties as compared with coal1 that some analyses of this gas1 together with calculations showing the comparison between its heating power and that of coal1 may be of interest4 ,these calculations are1 of course1 theoretical in both cases1 and it must not be imagined that the total amount of heat1 either in a ton of coal or #a1jjj cubic feet of natural gas1 can ever be fully utilized4 ,in making these calculations ,i employed as a basis what in my estimation was a gas of an average chemical composition1 as ,i have found that gas from the same well varies continually in its composition4 ,thus1 samples of gas from the same well1 but taken on different days1 vary in nitrogen from #bc per cent4 to nil1 carbonic acid from #b per cent4 to nil1 oxygen from #d per cent1 to #j4d per cent41 and so with all the component gases4 ,before giving the theoretical heating power of #a1jjj cubic feet of this gas ,i will note a few analyses4 ,the first four are of gas from the same well2 samples taken on the same day that they were analyzed4 ,the two last are from two different wells in the ,east ,liberty district3 ,,analyses ,,of ,,natural ,,gas4 ---------------------------------------- ---------------------------- #a #b #c #d #e #f ---------------------------------------- ---------------------------- ,when tested444444444#aj-bh-hdaj-bi-hdaa-bd-hd ab-d-hd #aj-ah-hdaj-be-hd per ct4 per ct4 per ct4 per ct4 per ct4 per ct4 ,carbonic acid 444444 #j4h #j4f ,nil4 #j4d ,nil4 #j4cj ,carbonic oxide444444 #a4j #j4h 4#eh #j4d #a4j #j4cj ,oxygen444 444 444444 #a4a #j4h 4#gh #j4h #b4aj #a4bj ,olefiant gas 4444444 #j4g #j4h #j4ih #j4f #j4hj #j4f ,ethylic hydride 4444 #c4f #e4e #g4ib #ab4cj #e4bj #d4h ,marsh gas 4444444444 #gb4ah #fe4be #fj4gj #di4eh #eg4he #ge4af ,hydrogen 44444444444 #bj4jb #bf4af #bi4jc #ce4ib #i4fd #ad4de ,nitrogen 44444444444 ,nil4 ,nil4 ,nil4 ,nil4 #bc4da #b4hi ,heat units 444444444#gbh1gdf #fih1heb #fbg1agj #gde1hac #eib1chj #gde1eia ---------------------------------------- ---------------------------- ,we will now show how the natural gas compares with coal1 weight for weight1 or1 in other words1 how many cubic feet of natural gas contain as many heat units as a given weight of coal1 say a ton4 ,in order to accomplish this end we will be obliged1 as ,i have said before1 to assume as a basis for our calculations what ,i consider a gas of an average chemical composition1 viz43 ,per cent4 ,carbonic acid4444444444444444444444444444 #j4fj ,carbonic oxide444444444444444444444444444 #j4fj ,oxygen444444444444444444444444444444444 44 #j4hj ,olefiant gas44444444444444444444444444444 #a4jj ,ethylic hydride44444444444444444444444444 #e4jj ,marsh gas4444444444444444444444444444444 #fg4jj ,hydrogen4444444444444444444444444444444 4 #bb4jj ,nitrogen4444444444444444444444444444444 44 #c4jj ,now1 by the specific gravity of these gases we find that #ajj liters of this gas will weigh #fd4hehe grammes1 thus3 ,weight1 ,liters4 grammes4 ,marsh gas44444444444444444 #fg4j #dh4jbef ,olefiant gas44444444444444 #a4j #a4becd ,ethylic hydride44444444444 #e4j #f4gbjj ,hydrogen444444444444444444 #bb4j #a4igab ,nitrogen444444444444444444 #c4j #c4gfcb ,carbonic acid4444444444444 #j4f #a4bbeg ,carbonic oxide444444444444 #j4f #j4gebf ,oxygen44444444444444444444 #j4h #a4adfh ------- ,total4444444444444444444444444444444444 4 #fd4hehe ,then1 if we take the heat units of these gases1 we will find3 ,heat units ,grammes4 contained4 ,marsh gas4444444444444444 #dh4jbef #fbg1ceh ,olefiant gas4444444444444 #a4becd #ad1iaj ,ethylic hydride4444444444 #f4gbjj #gg1fgi ,hydrogen44444444444444444 #a4igab #fg1ibi ,carbonic oxide44444444444 #j4gebf #a1hjh ,nitrogen44444444444444444 #c4gfcj ----- ,carbonic acid444444444444 #a4bbeg ----- ,oxygen4444444444444444444 #a4adfh ----- ------- ------- ,totals #fd4hehe #ghi1fid #fd4hehe grammes are almost exactly #a1jjj grains1 and #a cubic foot of this gas will weigh #bfg4i grains2 then the #ajj liters1 or #fd4hehe grammes1 or #a1jjj grains1 are #c1gfa cubic feet2 #c1gfa cubic feet of this gas contains #ghi1fid heat units1 and #a1jjj cubic feet will contain #baj1jfi1fjd heat units4 ,now1 #a1jjj cubic feet of this gas will weigh #bfe1hhg grains1 or in round numbers #ch lb4 avoirdupois4 ,we find that #fd4hehe grammes1 or #a1jjj grains1 of carbon contain #ebc1jdf heat units1 and #bfe1hhg grains1 or #ch lb41 of carbon contain #aci1cih1hif heat units4 ,then #eg4be lb4 of carbon contain the same number of heat units as #a1jjj cubic feet of the natural gas1 viz41 #baj1jfi1fjd4 ,now1 if we say that coke contains in round numbers #ij per cent4 carbon1 then we will have #fb4ig lb4 of coke1 equal in heat units to #a1jjj cubic feet of natural gas4 ,then1 if a ton of coke1 or #b1jjj lb41 cost #ajs41 #fb4ig lb4 will cost #d;d41 or #a1jjj cubic feet of gas is worth #d;d4 for its heating power4 ,we will now compare the heating power of this gas with bituminous coal1 taking as a basis a coal slightly above the general average of the ,pittsburg coal1 viz43 ,per cent4 ,carbon444444444444444444444444444444444 44 #hb4ge ,hydrogen4444444444444444444444444444444 44 #e4ca ,nitrogen4444444444444444444444444444444 44 #a4jd ,oxygen444444444444444444444444444444444 44 #d4fd ,ash444444444444444444444444444444444444 44 #e4ca ,sulphur44444444444444444444444444444444 44 #j4ie ,we find that #ch lb4 of this coal contains #adf1ijc1hbj heat units4 ,the #fd4d lb4 of this coal contains #baj1jfi1fdj heat units1 or #ed4d lb4 of coal is equal in its heating power to #a1jjj cubic feet of natural gas4 ,if our coal cost us #es4 per ton of #b1jjj lb41 then #ed4d lb4 costs #a4fcb;d41 and #a1jjj cubic feet of gas is worth for its heat units #a4fcb;d4 ,as the price of coal increases or decreases1 the value of the gas will naturally vary in like proportions4 ,thus1 with the price of coal at #ajs4 per ton the gas will be worth #c4bfd;d4 per #a1jjj cubic feet4 ,if #ed4d lb4 of coal is equal to #a1jjj cubic feet of gas1 then one ton1 or #b1jjj lb41 is equal to #cf1gfd cubic feet1 or #b1bdj lb4 of coal is equal to #dj1gfh cubic feet of natural gas4 ,if we compare this gas with anthracite coal1 we find that #a1jjj cubic feet of gas is equal to #eh4d lb4 of this coal1 and #b1jjj lb4 of coal is equal to #cd1bdf cubic feet of natural gas4 ,then1 if this coal cost #bfs4 per ton1 #a1jjj cubic feet of natural gas is worth #i;d4 for its heating power4 ,in collecting samples of this gas ,i have noticed some very interesting deposits from the wells4 ,thus1 in one well the pipe was nearly filled up with a soft grayish-white material1 which proved on testing to be chloride of calcium4 ,in another well1 soon after the gas vein had been struck1 crystals of carbonate of ammonia were thrown out1 and upon testing the gas ,i found a considerable amount of that alkali1 and with this well no chloride of calcium was observed until about two months after the gas had been struck4 ,in these calculations of the heating power of gas and coal no account is of course taken of the loss of heat by radiation1 etc4 ,my object has been to compare these two fuels merely as regards their actual value in heat units4 ,bearing in mind that it is never wise to prophesy unless you know1 ,i hesitate to speak of the future2 but considering the experience we have had in regard to the productiveness of the oil territory1 which is now yielding #gj1jjj barrels of petroleum per day1 and which has continued to increase year after year for twenty years1 ,i see no reason to doubt the opinion of experts that the territory which has already been proved to yield gas will suffice for at least the present generation in and about ,pittsburg4 99 99 99 99 99 ,a ,,gas-,,engine ,,water-,,supply ,,alarm4 ,illustration ,a very useful contrivance for the purpose of reporting automatically the failure of the water supply to a gas-engine has been arranged by ,professor ,ph4 ,carl1 of ,munich4 ,what led to the adoption of the device was that1 during last winter1 the water supply in the neighborhood of the ,professor's laboratory was several times cut off without previous notice2 the result being the failure of the water needed for cooling the cylinder of his ,otto gas-engine4 ,on inquiring into the matter1 he discovered that the same thing frequently occurred in other places where gas-engines were in use2 and this caused him to design a contrivance to put an alarm-bell into action at the instant when the water ceased to flow1 and so enable any overheating of the engine1 and injuries thereby resulting1 to be prevented in time4 ,the arrangement 7represented half size in the accompanying engraving7 is screwed down directly to the water outflow pipe1 ,r4 ,before the aperture of the pipe is a lever1 with a disk on one arm1 on to which the issuing water impinges1 thereby keeping the lever in the position indicated by the dotted lines4 ,the effect of this is to break the platinum contact at ,c1 and so interrupt the circuit of an alarm-bell placed in any suitable position4 ,suppose the water ceases to flow2 the spring1 ,f1 comes into play1 contact is made at ,c1 and the bell continues to ring till some one comes to stop it4 ,it is almost needless to remark that the disk1 ,d1 and the pin1 ,e1 are composed of insulating material1 such as vulcanite4--,jour4 ,gas ,lighting4 99 99 99 99 99 ,,soldering ,,and ,,repairing ,,platinum ,,vessels ,,in ,,the ,,laboratory4 ,by ,j4,w4 ,,pratt1 ,f4,c4,s4 ,it frequently happens in the laboratory that platinum vessels1 after long-continued use1 begin to show signs of wear1 and become perforated with minute pinholes4 ,when they have reached this stage1 they are usually accounted of no further utility1 and are disposed of as scrap2 not that it is impossible to repair them--for with fine gold wire and an oxyhydrogen jet this is easily feasible--but that the proper appliances and skill are not in possession of all4 ,irrespective of the manipulation of the hydrogen jet1 it is rather difficult without long practice to hold the end of the fine wire precisely over the aperture and to keep it in position4 ,it occurred to me that1 if the gold in a finely divided condition could be placed in very intimate contact with the platinum1 judging from the fusibility of gold-platinum alloys1 union could be effected at a lower temperature over the ordinary gas blowpipe4 ,i tried the experiment1 and found the supposition correct4 ,the substance ,i used was auric chloride1 ,au,cl#c1 which1 as is well known1 splits up on heating1 first into aurous chloride1 and at a higher temperature gives off all its chlorine and leaves metallic gold4 ,operating on a perforated platinum basin1 in the first instance1 ,i placed a few milligrammes of the aurous chloride from a #ae grain tube precisely over the perforation1 and then gently heated to about #bjj ,c4 till the salt melted and ran through the holes4 ,a little further heating caused the reduced gold to solidify on each side of the basin4 ,the blowpipe was now brought to bear on the bottom of the dish1 right over the particular spots it was wished to solder1 and in a few moments1 at a yellow-red heat 7in daylight71 the gold was seen to run4 ,on the vessel being immediately withdrawn1 a very neat soldering was evident4 ,the operation was repeated several times1 till in a few minutes the dish had been rendered quite tight and serviceable4 ,using the gold salt in this way1 the principal difficulty experienced in holding gold wire unflinchingly in the exact position vanishes1 while only a comparatively low temperature and small amount of gold is necessary4 ,care must be taken to withdraw the platinum from the flame just at the moment the gold is seen to run1 for if the heat be continued longer1 the gold alloys with a larger surface of platinum1 spreads1 and leaves the aperture empty4 ,as in the case of all gold-soldered vessels1 the article cannot afterward be safely exposed to a temperature higher than that at which the soldering was effected1 and on this account it is advisable to use as small an amount of auric chloride as possible4 ,when the perforations are of comparatively large size1 the repairing is not so easy1 owing to the auric chloride1 on fusing1 refusing to fill them4 ,i find1 however1 that if some spongy platinum be mixed with a few milligrammes of the gold salt1 pressed into the perforation1 and heat applied as directed1 a very good soldering can be effected4 ,it is well to hammer the surface of the platinum while hot1 so as to secure perfect union and welding of the two surfaces4 ,this may be done in a few minutes in such a manner as to render the repair indistinguishable4 ,strips of platinum may be joined together in much the same way as already described--a few crystals of auric chloride placed on each clean surface and gently heated till nearly black1 then bound together and further heated for a few moments in the blowpipe flame4 ,rings and tubes can also be formed on a mandrel1 and soldered in the same fashion1 and the chemist thus enabled to build up small pieces of apparatus from sheet platinum in the laboratory4--,chem4 ,news4 99 99 99 99 99 ,,the ,,helicoidal ,,or ,,wire ,,stone ,,saw4 ,the sides of solid bodies1 whatever be the degree of hardness1 and however fine the texture1 possess surfaces formed of a succession of projections and depressions4 ,when two bodies are in contact1 these projections and indentations fit into one another1 and the adherence that results is proportional to the degree of roughness of the surfaces4 ,if1 by a more or less energetic mechanical action1 we move one of the bodies with respect to the other1 we shall produce1 according as the action overcomes cohesion1 more or less disintegration of the bodies4 ,the resulting wear in each of them will evidently be inversely proportional to its hardness and the nature of its surface2 and it will vary1 besides1 with the pressure exerted between the surfaces and the velocity of the mechanical action4 ,we may say1 then1 that the wear resulting from rubbing two bodies against each other is a function of their degree of hardness1 of the extent and state of their surface1 of the pressure1 of the velocity1 and of the time4 ,illustration3 ,,figs4 #a1 #b and #c4--;,,apparatus ,,for ,,sawing ,,stone4 ,according as these factors are varied in a sense favorable or unfavorable to their proper action1 we obtain variations in the final erosion4 ,thus1 in rubbing together two bodies of different hardness and nature of surface1 we obtain a wear inversely proportional to the hardness and state of polish of their surfaces4 ,through the interposition of a pulverized hard body we can still further accelerate such wear1 as a consequence of the rapid renewal of the disintegrating element4 ,the gradual wear effected over the entire surface of a body brings about a polish1 while that effected along a line or at some one point determines a cleavage or an aperture4 ,the process usually employed in quarries or stone-yards for sawing consists in slowly moving a stone-saw backward and forward1 either by hand or machinery1 and with scarcely any pressure4 ,mr4 ,p4 ,gray has1 however1 devised a new process1 which is based upon the theoretical considerations given above4 ,his helicoidal saw is1 in reality1 an endless cable formed by twisting together three steel wires in such a way as to give the spirals quite an elongated pitch4 ,the apparatus in its form for cutting blocks of stone into large slabs 7,figs4 #a1 #b1 and #c7 consists of two frames1 ,a ,a1 five feet apart1 each formed of two iron columns1 #g feet in height and one foot apart1 fixed to cast iron bases resting upon masonry4 ,at the upper part1 a frame1 ,b ,b1 formed of double ,t-irons cross-braced here and there1 supports a transmission composed of gearwheels1 ,r ,r1 and a pitch-chain1 ,g ,g4 ,along the columns of the frame1 which serve as guides1 move two kinds of pulley-carriers1 ,c ,c4 ,the pulleys1 ,d ,d1 are channeled1 and receive the cable1 a a1 which serves as a helicoidal saw4 ,the direction of the saw's motion is indicated by the arrow4 ,the carriages1 ,c ,c1 are traversed by screws1 ,v ,v1 which are fixed between the columns4 ,the extremity1 v1 of the axle of the pulley to the right is threaded1 and actuates a helicoidal wheel1 ,e1 which transmits motion to the wheel1 ,r1 through the intermedium of the vertical shaft1 ,f4 ,this transmission1 completed by the wheels1 ,r ,r1 and the pitch-chains1 ,g ,g1 is designed to move the saw vertically1 through the simultaneous shifting of the carriages1 ,c ,c4 ,a tension weight1 ,p1 through the intermedium of pulleys1 ,d#a ,d#a1 permits of keeping the saw taut4 ,a reservoir1 ,h1 at the upper part of the frame1 ,b ,b1 contains the water and sand necessary for sawing4 ,the feeding is effected by means of a rubber tube1 ,i1 terminating in a flattened rose1 ,j1 which is situated over the aperture made by the saw4 ,a small pump1 ,l4 over the reservoir takes water from ,k1 and raises it to ,h4 ,the sand is put in by hand4 ,above the basin1 ,k1 a system of rails and ties supports the carriage1 ,q1 upon which is placed the block of stone to be sawn4 ,when one operation has been finished1 and it is desired to begin another1 it is necessary to raise the pulley-carriers and the saw4 ,in order to do this quickly1 there is provided a special transmission1 ,m1 which is actuated by hand1 through a winch4 ,the work done by this saw is effected more rapidly than by the ordinary processes1 and certain very hard rocks1 usually regarded as almost intractable1 can be sawed at the rate of from one to one and a half inches per hour4 ,illustration3 ,,fig4 #d4--;,,apparatus ,,for ,,sawing ,,stone ,,into ,,slabs4 ,for sawing marble into slabs of all thicknesses1 the arrangement described above may be replaced by a system consisting of two drums having several channels to receive as many saws1 or two corresponding series of channeled pulleys1 b b 7,fig4 #d71 independent of each other1 but keyed to the same axles1 i i4 ,when the pulleys have been properly spaced by means of keys1 the whole affair is rendered solid by a bolt1 g4 ,the extremity of the axles forms a nut into which pass vertical screws1 c c4 ,these latter are connected above with cone-wheels1 l l1 which1 gearing with bevel wheels keyed to the shafts1 e1 secure a complete interdependence of the whole4 ,the ascending motion1 which is controlled by the endless screws1 f1 and the helicoidal wheels1 m1 is in this way effected with great regularity4 ,uprights1 a a1 of double ,t-iron1 fixed to joists1 k k1 and connected and braced by pieces1 d d1 form a strong frame4 ,illustration3 ,,fig4 #e4--;,,application ,,of ,,gay',s ,,stone ,,saw ,,in ,a ,,marble ,,quarry4 ,the power necessary to run this kind of saw is less than n ,h4,p41 on account of the number of passive parts4 ,the most interesting application of the helicoidal saw is in the exploitation of quarries4 ,fig4 #e represents a ,belgian marble quarry which is being worked by ,mr4 ,gay's method4 ,tubular ,perforators4--,mr4 ,gay has rendered his saw completer by the invention of a tubular perforator for drilling the preliminary well4 ,it is based upon the same principle as the ,leschot rotary drill1 but differs from that in its extremity being simply of tempered steel instead of being set with black diamonds4 ,a special product1 called metallic agglomerate1 is used instead of sand for hastening the work4 ,illustration3 ,,fig4 #f4--,,tubular ,,perforator4 ,the apparatus1 ,fig4 #f1 consists of an iron plate cylinder1 ,a1 #bg inches in diameter1 and of variable length1 according to the depth to be obtained1 and terminating beneath in a steel head1 ,b1 of greater thickness4 ,this cylinder is traversed by a shaft1 ,c1 to which it is keyed1 and which passes through the center of the aperture drilled4 ,this shaft is connected with the cylinder1 ,a1 through the intermedium of cross bars1 ,d1 and transmits thereto a rapid rotary motion1 which is received at the upper part from a telodynamic wire that passes through the channel of the horizontal pulley1 ,p4 ,this latter is supported by a frame consisting of three uprights1 ,q ,q1 strengthened by stays1 ,r ,r1 fixed to the ground4 ,in order that the cylinder1 ,a1 may be given a vertical motion1 cords1 ,m ,m1 fixed to a piece1 ,s1 loose on the hub1 ,d1 wind round the drum of a windlass1 ,t1 after passing over the pulleys1 p p4 ,the rapid gyratory motion of the cylinder1 along with the erosive action of the metallic agglomerate1 rapidly wears away the rock1 and causes the descent of the perforator4 ,during this operation a core of marble forms in the cylinder4 ,this is detached by lateral pressure1 and is capable of being utilized4 ,the tool descends at the rate of from #bj to #bd inches per hour1 or from #h to #aj yards per day in ordinary lime rock4--,le ,genie ,civil4 99 99 99 99 99 ,,portable ,,prospecting ,,drill4 ,illustration3 ,,portable ,,prospecting ,,drill4 ,the ,aqueous ,works and ,diamond ,rock-boring ,company1 ,limited1 of ,london1 show at the ,inventions ,exhibition1 ,london1 a light portable rock-boring machine for prospecting for minerals1 water1 etc4 ,it is capable of sinking holes from #b in4 to #e in4 in diameter1 and to a depth of #djj ft4 ,the screwed boring spindle1 which is in front of the machine1 is actuated by miter gearing driven by a six horse power engine2 the speed of driving is #djj revolutions a minute4 ,the pump shown on the left-hand side of the engraving is used to deliver a constant stream of water through the boring bar1 the connection being made by a flexible hose4 ,suitable winding gear for raising or lowering the lining tubes1 boring rods1 etc41 is also mounted on the same frame4 ,the drill is automatic in its action1 and the speed can be regulated by friction gearing4 ,the front part of the carriage is arranged so that it can be swung clear of the drill to raise and lower the bore rods1 etc4 99 99 99 99 99 ,,automatic ,,safety ,,gear4 ,among the safety appliances which are to be found in the ,mining ,section of the ,inventions ,exhibition is a model of an ingenious contrivance for the prevention of overwinding1 the joint patent of ,mr4 ,w4,t4 ,lewis1 ,aberdare1 lead mineral agent to the ,marquis of ,bute1 and ,w4,h4 ,massey1 electric light engineer to the ,queen4 ,both these gentlemen1 having been members of jury1 were not allowed to compete for an award4 ,the invention1 says ,engineering1 seems to possess considerable merit1 and it should prove of practical utility in collieries where enginemen are usually kept winding for many hours at a stretch1 and where the slightest mistake on the part of the driver may lead to an accident4 ,safety hooks are often fitted to winding ropes1 and although the damage to life and property is greatly reduced by the use of them1 they do not protect a descending cage from injury in a case of overwinding2 besides which1 they are almost useless when a wild run takes place1 an accident which1 strange to say1 has already occurred many times after engines and boilers have been laid off for repairs4 ,stop valves are left open1 the reversing lever is not fixed in mid-gear1 steam is got up in the boilers at a time when no one is in the engine house1 and the engines run away4 ,illustration3 ,,lewis ,,massey',s ,,automatic ,,safety ,,gear4 ,various devices have been suggested and tried as a preventive1 but their application has either caused as much mischief as a bad accident1 or it has depended upon the driver doing something intentionally2 whereas in the automatic gear of ,messrs4 ,massey and ,lewis1 of which an illustration is annexed1 there is nothing to cause damage or to interfere in any way with the proper handling of the engines1 and it is practically out of the power of the driver to render the gear inoperative4 ,it is here shown in its simplest form as applied to the ordinary reversing and steam handles of a winding engine1 the only additions being an arm jointed to the top of the valve spindle1 with its connections to the shaft of the reversing lever1 and a disk receiving a suitable motion from the main shaft of the engine4 ,on the disk is a projecting piece or stop which is brought into such positions1 at or near the end of each journey1 that the stop valve cannot be opened1 except slightly1 when the reversing lever is not set for winding in the proper direction1 or when the cages have reached a point beyond which it is undesirable that the engine driver should have the power of turning on full steam4 ,thus1 if one cage is at bank1 the driver cannot draw it up into the head gear suddenly2 but after it has been lifted slowly off the keeps or fangs1 and the reversing lever thrown over1 the stop valve can be lifted wide open2 and supposing that while the engine is running the driver neglects to shut off steam in proper time1 then the projecting piece on the disk in traveling round1 slowly or quickly1 and by steps according to requirements1 will come in contact with the driver1 and so prevent an accident by bringing the reversing lever into or beyond mid-gear4 ,messrs4 ,lewis and ,massey contemplate the use of governors in combination with various forms of their automatic gear1 so as to provide for every imaginable case of winding1 and also to avoid accidents when heavy loads are sent down a pit2 the special feature in their mechanism being that when two or more things happen with regard to the positions of steam or reversing handles1 speed or position of cages in the pit1 whatever it may be necessary to do to meet the particular case shall be done automatically4 99 99 99 99 99 ,,the ,,water ,,supply ,,of ,,ancient ,,roman ,,cities4 ,footnote3 ,an address by ,prof4 ,w4,h4 ,corfield1 ,m4,d41 ,m4,a41 delivered before the ,sanitary ,institute of ,great ,britain1 ,july #i1 #ahhe4--;,building ,news4 ,as the supply of water to large populations is one of the most important subjects in connection with sanitary matters1 and one upon which the health of the populations to a very large extent depends1 ,i propose to give a short account of some of the more important works carried out for this purpose by the ancient ,romans--the great sanitary engineers of antiquity--more especially as ,i have had exceptional opportunities of examining many of those great works in ,italy1 in ,france1 and along the north coast of ,africa4 ,of the aqueducts constructed for the supply of ,rome itself we have an excellent detailed account in the work of ,frontinus1 who was the controller of the aqueducts under the emperor ,nerva1 and who wrote his admirable work on them about ,a4,d4 #ig4 ,it may be interesting in passing to mention that ,frontinus was a patrician1 who had commanded with distinction in ,britain under the emperor ,vespasian1 before he was appointed by the emperor ,nerva as controller 7or1 we should say1 surveyor7 of the aqueducts4 ,he was also an antiquarian1 and in his work he not only describes the aqueducts as they were in this time1 but also gives a very interesting history of them4 ,he begins by telling us that for #dda years after the building of the city--that is to say1 ,b4,c4 #cab--there was no systematic supply of water to the city2 that the water was got direct from the ,tiber1 from shallow wells1 and from natural springs2 but that these sources were found no longer to be sufficient1 and the construction of the first aqueduct was undertaken during the consulship of ,appius ,claudius ,crassus1 from whom it took the name of the ,appian aqueduct4 ,this was1 as may be expected from its being the first aqueduct1 not a very long one2 the source was about eight miles to the east of ,rome1 and the length of the aqueduct itself rather more than eleven miles1 according to ,mr4 ,james ,parker1 to whose paper on the ,water ,supply of ,ancient ,rome ,i am indebted for many of the facts concerning the aqueducts of ,rome itself4 ,this aqueduct was carried underground throughout its whole length1 winding round the heads of the valleys in its course1 and not crossing them1 supported on arches1 after the manner of more recent constructions2 it was thus invisible until it got inside the city itself1 a very important matter when we consider how liable ,rome was1 in these early times1 to hostile attacks4 ,it was soon found that more water was required than was brought by this aqueduct1 and it was no doubt considered desirable to have tanks at a higher level in the city than those supplied by the ,appian aqueduct4 ,it was determined1 therefore1 to bring water from a greater height1 and from a greater distance1 and the river ,anio1 above the falls at ,tivoli1 was selected for this purpose4 ,the second aqueduct1 the ,anio ,vetus1 was no less than #db miles in length1 and was1 like the ,appian1 entirely under the surface of the ground1 except at its entrance into ,rome at a point about #fj ft4 higher than the level of the ,appian aqueduct4 ,little search has been made for the remains of this aqueduct1 and its exact course is not known2 but during my examination of the remains of the subsequent aqueducts at a place called the ,porta ,furba1 near ,rome1 where the ruins of five aqueducts are seen together1 and at1 or close to1 which point the ,anio ,vetus must also have passed underground1 ,i was rewarded for my search by discovering a hole1 something like a fox's hole1 leading into the ground2 and on clearing away a few loose stones which had apparently been thrown into it1 and putting my arm in1 ,i found that it led into the specus or channel of an underground aqueduct2 and on relating this incident to the late ,mr4 ,john ,henry ,parker1 the antiquarian1 who was then in ,rome1 and showing him a sketch of the place1 he said that he had no doubt that ,i had been fortunate enough to discover the exact position of the veritable ,anio ,vetus at that spot4 ,these two aqueducts sufficed for the supply of ,rome with water for about #abj years1 for ,frontinus tells us that #abg years after the date at which the construction of the ,anio ,vetus was undertaken--that is to say1 the #fjhth year after the foundation of the city--the increase of the city necessitated a more ample supply of water1 and it was determined to bring it from a still greater distance4 ,it was no longer considered necessary to conceal the aqueduct underground during the whole of its course1 and so it was in part carried above ground on embankments or supported upon arches of masonry4 ,the water was brought from some pools in one of the valleys on the eastern side of the ,anio1 some miles farther up than the point from which the ,anio ,vetus was supplied2 and the new aqueduct1 which was #ed miles in length1 was called the ,marcian1 after the ,prtor ,marcius1 to whom the work was intrusted4 ,frontinus also tells us the history of the other six aqueducts which were in existence in his time1 viz41 the ,tepulan1 the ,julian1 the ,virgo1 the ,alsietine or ,augustan1 the ,claudian1 and the ,anio ,novus2 the last two being commenced by the ,emperor ,caligula1 and finished by ,claudius1 because seven aqueducts seemed scarcely sufficient for public purposes and private amusements2 but it is not necessary for our purpose to give any detailed account of the course of these aqueducts2 it is only necessary to mention one or two very interesting points in connection with them4 ,in order to allow of the deposit of suspended matters1 piscin1 or settling reservoirs1 were constructed in a very ingenious manner4 ,each had four compartments1 two upper and two lower2 the water was conducted into one of the upper compartments1 and from this passed1 probably by what we should call a standing waste or overflow pipe1 into the one below2 from this it passed 7probably through a grating7 into the third compartment at the same level1 and thence rose through a hole in the roof of this compartment into the fourth1 which was above it1 and in which the water1 of course1 attained the same level as in the first compartment1 thence passing on along the aqueduct1 having deposited a good deal of its suspended matter in the two lower compartments of the piscin4 ,arrangements were made by which these two lower compartments should be cleaned out from time to time4 ,the specus or channel itself was1 of course1 constructed of masonry1 generally of blocks of stone cemented together1 and it was frequently1 though not1 it would appear always1 lined with cement inside4 ,it was roofed over1 and ventilating shafts were constructed at intervals2 in order to encourage the aeration of the water1 irregularities were occasionally introduced in the bed of the channel4 ,the water supplied by the different aqueducts was of various qualities2 thus1 for instance1 that of the ,alsietine1 which was taken from a lake about #ah miles from ,rome1 was of an inferior quality1 and was chiefly used to supply a large naumachia1 or reservoir1 in which imitation sea fights were performed2 while1 on the other hand1 the water of the ,marcian was very clear and good1 and was therefore used for domestic purposes4 ,frontinus gives the most accurate details as to the measurements of the amount of water supplied by the various aqueducts1 and the quantities used for different purposes4 ,from these details ,mr4 ,parker computes the sectional area of the water at about #abj square feet1 and says3 ,we can form some opinion of the vast quantity if we picture to ourselves a stream #bj ft4 wide by #f ft4 deep constantly pouring into ,rome at a fall six times as rapid as that of the river ,thames4 ,he considers that the amount was equivalent to about #ccb million gallons a day1 or #ccb gallons per head per day1 assuming the population of the city to be a million4 ,when we consider that we in ,london have only #cj gallons a head daily1 and that many other towns have less1 we get some idea of the profusion with which water was supplied to ancient ,rome4 ,but the remains of ,roman aqueducts are not only to be found near ,rome4 ,almost every ,roman city1 whether in ,italy or in the south of ,france1 or along the north coast of ,africa1 can show the remains of its aqueduct1 and almost the only things that are to be seen on the site of ,carthage are the remains of the ,roman water tanks and the ruins of the aqueduct which supplied them4 ,the most beautiful aqueduct bridge in the world1 on the course of the aqueduct which supplied the ancient ,nemaucus1 now ,nismes1 still stands1 and is called1 from the name of the department in which it is1 the ,pont du ,gard4 ,it consists of a row of large arches crossing the valley over which the water had to be carried1 surmounted by a series of smaller arches1 and these again by a series of still smaller ones1 carrying the specus of the aqueduct4 ,this splendid bridge still stands perfect1 so that one can walk through the channel along which the water flowed1 and it might be again used for its original purpose4 ,there was1 however1 one city which1 from the fact that a great part of it was situated upon a hill1 was more difficult to supply with water than any of the rest1 and which1 at the same time1 from its size1 its great importance1 and the fact that it was the favorite summer residence of several of the ,roman emperors1 and notably of ,claudius1 who was born there1 and who had a palace on the top of the hill1 must of necessity be supplied with plenty of water1 and that too from a considerable height4 ,i refer to ,ludgunum 7now ,lyons71 then the capital of ,southern ,gaul4 ,this city was built by ,lucius ,munatius ,plaucus1 by order of the ,senate in ,a4,u4,c4 #gaa4 ,augustus went there in ,a4,u4,c4 #gch1 and afterward lived there from #gda to #gdd4 ,it was he who raised it to a very high rank among ,roman cities4 ,it had its forum near the top of the hill now called ,fourvieres 7probably a corruption of ,forum ,vetus71 an imperial place on the summit of the same hill1 public baths1 an amphitheater1 a circus1 and temples4 ,in order to supply this city with water1 standing as it did on the side of a hill at the junction of two great rivers 7now ,rhone and ,saone71 it was necessary to search for a source at a sufficient height1 and this ,plaucus found in the hills of ,mont d',or1 near ,lyons1 where a plentiful supply of water was found at a sufficient height1 viz41 that of nearly #b1jjj ft4 above the sea4 ,from this point an aqueduct1 sometimes called from its source the aqueduct of ,mont d',or1 and sometimes the aqueduct of ,ecully1 from the name of a large plain which it crossed1 was constructed1 or rather two subterranean aqueducts were made and joined together into one1 which crossed the plain of ,ecully1 in a straight line still underground2 but the ground around ,lyons was not like the ,campagna1 near ,rome1 and it was necessary to cross the broad and deep valley now called ,la ,grange1 ,blanche4 ,this1 however1 did not daunt the ,roman engineers2 making the aqueduct end in a reservoir on one side of the valley1 they carried the water down into the valley1 probably by means of lead pipes1 in the manner which will be described more at length further on1 across the stream at the bottom of the valley by means of an aqueduct bridge #fej ft4 long1 #ge ft4 high1 and #bh ft4 broad1 and up the other side into another reservoir1 from which the aqueduct was continued along the top of a long series of arches to the reservoir in the city1 after a course of about ten miles4 ,in the time of ,augustus1 however1 it was found that the water brought by this aqueduct was not sufficient1 especially in summer2 and as there was a large ,roman camp which also required to be supplied with water1 situated at a short distance from the city1 it was determined to construct a second aqueduct4 ,for this purpose the springs at the head of a small river1 called now the ,brevenne1 were tapped1 and conveyed by means of an underground aqueduct 7known as the aqueduct of the ,brevenne7 which wound round the heads of the valleys1 and after a course of about thirty miles is believed by some to have arrived at the city1 but by others to have stopped at the ,roman camp1 and to have been constructed exclusively for its supply4 ,i have here a diagram1 after ,flacheron1 showing a section of this aqueduct1 and this will give a very good general idea of the section of a ,roman aqueduct where constructed underground4 ,it will be seen that the specus or channel is #fj centimeters 7or nearly #b ft47 wide1 and #am4 #eg;c4 7or a little over #e ft47 high1 and that it is lined with a layer of #c c4 7or nearly #a in47 of cement4 ,it is constructed of quadrangular blocks of stone cemented together1 and has an arched stone roof4 ,it will be noticed also that the angles at the lower part of the channel are filled up with cement2 it appears also that this aqueduct crossed a small valley by means of inverted siphons4 ,but neither of these aqueducts came from a source sufficiently high to supply the imperial palace on the top of ,fourvieres4 ,their sources are1 in fact1 according to ,flacheron1 at a height of nearly #ej ft4 below the summit of ,fourvieres1 and it was1 therefore1 considered necessary by the emperor ,claudius to construct a third aqueduct4 ,the sources of the stream now called the ,gier1 at the foot of ,mont ,pila1 about a mile and a half above ,st4 ,chamond1 were chosen for this purpose1 and from this point to the summit of ,fourvieres was constructed by far the most remarkable aqueduct of ancient times1 an engineering work which1 as will be seen from the following description1 partly taken from ,montfalcon's history of ,lyons1 partly from ,flacheron's account of this aqueduct1 and partly from my own observations on the spot1 reflects the greatest possible credit on the ,roman engineers1 and shows that they were not1 as has been frequently supposed by those who have only examined aqueducts at ,rome1 by any means ignorant of the elementary principles of hydraulics4 ,to tap the sources of a river at a point over #ej miles from the city1 and to bring the water across a most irregular country1 crossing ten or twelve valleys1 one being over #cjj ft4 deep1 and about two-thirds of a mile in width1 was no easy task2 but that it was performed the remains of the aqueduct at various parts of its course show clearly enough4 ,it commences1 as ,i have said1 about a mile and a half from the present ,st4 ,chamond1 a town on the river ,gier1 about #af miles from ,st4 ,etienne4 ,here a dam appears to have been constructed across the bed of the river1 forming a lake from which the water entered the channel of the aqueduct1 which passed along underground until it came to a small stream which it crossed by a bridge1 long since destroyed4 ,after this it again became subterraneous for a time1 and then crossed another stream on a bridge of nine arches1 the ruins of some of the columns of which are still to be seen2 and from these ruins it would appear that the bridge had1 at some time or another1 been destroyed1 probably by the stream running under it having become torrential1 and subsequently rebuilt2 again it became concealed underground1 to reappear in crossing a small valley and another small stream1 when it was again concealed by the ground1 and in one or two places channels were even cut for it through the solid rock1 after which it reappeared on the surface at a point where now stands the village of ,terre-,noire1 and where it was necessary that it should somehow or another cross a broad and deep valley4 ,it ended in a stone reservoir1 from which eight lead pipes descending into the valley were carried across the stream at the bottom on an aqueduct bridge1 about #be ft4 wide1 and supported by twelve or thirteen arches1 and then mounted the other side of the valley into another reservoir1 of which scarcely any remains are now seen1 from which the aqueduct started again1 disappearing almost immediately under the surface of the ground1 to appear again from time to time crossing similar valleys and streams upon bridges1 the remains of some of which may still be seen1 until it reached ,soucieu1 on the edge of the valley of the ,garonne1 where are still seen the remains of a splendid bridge1 the thirteenth on its course1 nearly #a1fjj ft4 long1 and attaining a height of #ef ft4 at its highest point above the ground4 ,the object of this bridge was to convey the channel of the aqueduct at a sufficient height into a reservoir on the edge of the valley4 ,the remains of this bridge leave no doubt that it was purposely destroyed by barbarians2 some of the arches near the end of it remain1 while the rest have been thrown down1 some on one side and some on the other2 but happily the arches next to the reservoir1 at the end of the bridge and on the edge of the valley1 remain1 and the reservoir itself is still in part intact1 supported on a huge mass of masonry4 ,four holes are to be seen in that part of the front of the reservoir which is left1 being the holes from which the lead pipes descended into the valley4 ,there must have been nine of these pipes in all4 ,these holes are elliptical in shape1 being #ab in4 high by #i in4 wide1 and the interior of the reservoir is still seen to be covered with cement4 ,the walls of the reservoir were about #b ft4 #g in4 thick1 and were strengthened by ties of iron2 it had an arched stone roof in which there was an opening for access4 ,from this the nine lead pipes descended the side of the valley supported on a construction of masonry1 crossed the river by an aqueduct bridge1 and ascended into another reservoir on the other side1 entering the reservoir at its upper part just below the spring of the arches of the roof4 ,from this reservoir the aqueduct passed to the next on the edge of the large and deep valley of ,bonnan1 being underground twice and having three bridges on its course1 the last of which1 the sixteenth on the course of the aqueduct1 ends in a reservoir on the edge of the valley4 ,only one of the openings by which the siphons1 of which there were probably ten1 started from the reservoir is now left4 ,the bridge across the valley below had thirty arches1 and was about #hhj ft4 long by #bd ft4 wide4 ,a number of the arches still remain standing1 and1 the pillars of the arches were constructed of transverse arches themselves4 ,the work consisted of concrete1 formed with ,roman cement so hard that it turns the points of pickaxes when employed against it1 with layers of tiles at regular intervals4 ,the surface of the concrete is covered with small cubical blocks of stone placed so that their diagonals are horizontal and vertical1 and forming what is known as opus reticulatum4 ,after crossing the bridge the pipes were carried up the other side of the valley into a reservoir1 of which little remains1 and then the aqueduct was continued to the next valley1 passing over three bridges in its course4 ,this valley1 that of ,st4 ,irene1 is much smaller than either of the others1 but nevertheless it was deep enough to necessitate the construction of inverted siphons1 of which there were eight4 ,leaving the reservoir on the other side of this valley1 the aqueduct was carried on a long bridge 7the twentieth on its course7 which crossed the plateau on the top of ,fourvieres and opened into a large reservoir1 the remains of which are still to be seen on the top of that hill4 ,from this reservoir1 which was #gg ft4 long and #ea ft4 wide1 pipes of lead conveyed the water to the imperial palace and to the other buildings near the top of the hill4 ,some of these lead pipes were found in a vineyard near the top of ,fourvieres at the beginning of the eighteenth century1 and were described by ,colonia in his history of ,lyons4 ,they are made of thick sheet lead rolled round so as to form a tube1 with the edges of the sheet turned upward1 and applied to one another in such a way as to leave a small space1 which was probably filled with some kind of cement4 ,these pipes1 of which it is said that twenty or thirty1 each from #ae ft4 to #bj ft4 long1 were found1 were marked with the initial letters ,,ti4 ,,cl4 ,,caes4 7,tiberius ,claudius ,csar71 and afford positive evidence that the work was carried out under the emperor ,claudius4 ,lead pipes1 constructed in a similar manner1 have also been found at ,bath1 in this country1 in connection with the ,roman baths4 ,the great difference between this aqueduct and those near ,rome arises from the fact that1 instead of being carried across a nearly flat country1 it was carried across one intersected with deep ravines1 and that it was therefore necessary to have recourse to the system of inverted siphons4 ,there can be no doubt that the inverted siphons were made of lead1 although no remains of them have been found2 for we know that the ,romans used lead largely1 and1 as we have seen1 pieces of the lead distribution pipes have been found4 ,it is possible1 and even likely1 that strong cords of hemp were wound round the pipes forming the siphons1 as is related by ,delorme in describing a similar ,roman aqueduct siphon near ,constantinople2 ,delorme also describes1 in the aqueduct last mentioned1 a pipe for the escape of air from the lowest part of the siphon carried up against a tower1 which was higher than the aqueduct1 and it is certain that there must have been some such contrivance on the siphons of the aqueduct constructed at ,lyons4 ,flacheron supposes that they consisted of small pipes carried from the lowest part of the siphons up along the side of the valley and above the reservoirs1 or1 in some instances1 of taps fixed at the lowest part of the siphons4 ,the ,romans have been blamed for not using inverted siphons in the aqueducts at ,rome1 and it has been said that this is a sufficient proof that they did not understand the simplest principles of hydraulics1 but the remains of the aqueducts at ,lyons negative this assumption altogether4 ,the ,romans were not so foolish as to construct underground siphons1 many miles long1 for the supply of ,rome2 but where it was necessary to construct them for the purpose of crossing deep valleys1 they did so4 ,the same emperor ,claudius who built the aqueduct at ,rome known by his name built the aqueduct of ,mont ,pila1 at ,lyons1 and it is quite clear1 therefore1 that his engineers were practically well acquainted with the principles of hydraulics4 ,it is thus seen that the ancient ,romans spared no pains to obtain a supply of pure water for their cities1 and ,i think it is high time that we followed their example1 and went to the trouble and expense of obtaining drinking water from unimpeachable sources1 instead of1 as is too often the case1 taking water which we know perfectly well has been polluted1 and then attempting to purify it for domestic purposes4 99 99 99 99 99 ,,steam ,,engine ,,economy4 ,by ,chief ,engineer ,,john ,,lowe1 ,u4,s4 ,navy4 ,the purpose of this article is to point out an easy method whereby any intelligent engineer can determine the point at which it is most economical to cut off the admission of steam into his cylinder4 ,in the attack upon such a problem1 it is useful to employ all the senses which can be brought to bear upon it2 for this purpose1 diagrams will be used1 in order that the sense of sight may assist the brain in forming its conclusions4 ,illustration3 ,,steam ,,engine ,,economy4--,,by ,,john ,,lowe1 ,,chief ,,engineer ,u4,s4,n4 ,fig4 ,,xabcx is an ideal indicator card1 taken from a cylinder1 imagined to be #fjj feet long1 in which the piston1 making one stroke per minute1 has therefore a piston speed of #fjj feet per minute4 ,divide this card into any convenient number of ordinates1 distant dx feet from each other1 writing upon each the absolute pressure measured upon it from the zero line ,,xx4 ,by way of example1 let the diameter of the cylinder be #bi4ei inches1 and let the back pressure from all causes be #g pounds uniformly throughout4 ,it will be represented by the line b#a1 b#b1 etc4 ,this quantity subtracted from the pressures p#a1 p#b1 etc41 leaves the remainder 7p-b7 upon each ordinate1 which remainder represents the net pressures which at that point may be applied to produce external power4 ,if1 now1 ,a is the area of the piston1 then the external power 7d ,w7 produced between each ordinate is3 ,to any convenient scale1 upon each ordinate1 set off the appropriate power as calculated by this equation 7#a74 ,a7p-b7dx d,w --------------4 7#a47 #cc1jjj ,there will result the curve w1 w1 w1 determining the power which at any point in the diagram is to be regarded as a gain1 to be carried to the credit side of the account4 ,it is evident that1 so long as the gains from expansion exceed the losses from expansion1 it is profitable to proceed with expansion1 but that expansion should cease at that point at which gains and losses just balance each other4 ,,to ,,calculate ,,the ,,losses4 ,the requisite data are furnished by the experiments conducted some years since by ,president ,d4,m4 ,greene1 of ,troy ,college1 for the ,bureau of ,steam ,engineering1 ,u4,s4 ,navy4 ,according to these experiments1 the heat which is lost per hour by radiation through a metallic plate of ordinary thickness1 exposed to dry air upon one side and to the source of heat upon the other1 for one degree difference in temperature1 is as follows3 ,condition4 ,heat units4 ,naked4444444444444444444444444444444444 4444 #b4iccjfgb ,covered with hair felt1 #j4be inch thick4444 #a4jedjgaj #j4ej 4444 #j4egbhfdg #j4ge 4444 #j4dabdfbe #a4jj 4444 #j4cjgjeed #a4be 4444 #j4bgdfchg #a4ej 4444 #j4bejgjig ,if now t' temperature of steam at the ordinate1 t temperature of the surrounding atmosphere1 d,s surface of the cylinder included between each ordinate1 k that figure from the table satisfying the conditions1 then the power loss 7d,r7 per minute will be3 k 7t'-t7d,s d,r 7 -- 7 ----------4 7#b7 #fj #cc1jjj ,to the same scale as the power gains1 upon each ordinate1 set off the appropriate power loss1 as calculated by this equation 7#b74 ,there will result the curve r1 r1 r1 which determines the power which at any point in the diagram is to be regarded as a loss1 to be carried to the debit side of the account4 ,this curve of losses intersects the curve of gains at a point 7it is evident7 where each equals the other4 ,therefore this is the point at which expansion should cease1 and this absolute pressure is the economic terminal pressure1 which determines the number of expansions profitable under the given conditions4 ,in the foregoing example are taken k #j4cjgjeed1 t' #cca4afi1 t #fj1 while the back pressure was taken at #g pounds4 ,by way of further illustration1 first let the back pressure be changed from #g to #e4 ,by equation #a there will result a new curve of gains1 ,w1 ,w1 ,w1 a portion only being plotted4 ,second1 let t' #cca4afi as before4 t #aej instead of #fj4 k #j4bejgjig instead of #j4cjgjeed4 ,there will result the second curve of losses1 ,r1 ,r1 ,r1 intersecting the second curve of gains at the point ,f1 the new economic point for our new conditions4 ,these two examples fully illustrate the whole subject1 furnishing an easy and1 when carefully made1 a very exact calculation and result4 ,the following are a few of the general conclusions to be drawn3 #a4 ,that radiation is a tangible and measurable cause1 sufficient to account for all losses heretofore ascribed to an intangible1 immeasurable1 and wholly imaginary cause1 viz41 internal evaporation and re-evaporation4 #b4 ,in order to prevent the high initial temperatures now used becoming a source of loss1 it is necessary to prevent the quantity d,s 7t'-t7 becoming great1 by making d,s as small as possible4 ,in other words1 we must compound our engines4 ,thus for the first time is pointed out the true reason why compound engines are economical heat engines4 #c4 ,the foregoing reasoning being correct1 it follows that steam jackets are a delusion4 #d4 ,in order to attain economy1 we must have high initial temperatures1 small high pressure cylinders1 low back pressures from whatsoever cause1 high piston speeds1 short rather than long strokes1 to avoid the cooling effects of a long piston rod2 but especially must we have scrupulous and perfect protection from radiation1 especially about the cylinder heads1 now oftentimes left bare4 99 99 99 99 99 ,,electricity ,,in ,,warfare4 ,footnote3 ,from a recent lecture before the ,franklin ,institute1 ,philadelphia4 ,by ,lieut4 ,b4,a4 ,,fiske1 ,u4,s4,n4 ,lieutenant ,fiske began by paying a tribute to the remarkable pioneer efforts of ,colonel ,samuel ,colt1 who more than forty years ago blew up several old vessels1 including the gunboat ,boxer and the ,volta1 by the use of electricity4 ,congress voted ,colt #ag1jjj for continuing his experiments1 which at that day seemed almost magical2 and he then blew up a vessel in motion at a distance of five miles4 ,lieut4 ,fiske next referred briefly to the electrical torpedoes employed in the ,crimean war and our civil war4 ,at the present day1 an electrical torpedo may be described as consisting of a strong1 water-tight vessel of iron or steel1 which contains a large amount of some explosive1 usually gun-cotton1 and a device for detonating this explosive by electricity4 ,the old mechanical mine used in our civil war did not know a friendly ship from a hostile one1 and would sink either with absolute impartiality4 ,but the electrical submarine mine1 being exploded only when a current of electricity is sent through it from ship or shore1 makes no such mistake1 and becomes harmless when detached from the battery4 ,the condition of the mine at any time can also be told by sending a very minute current through it1 though miles away and buried deep beneath the sea4 ,when a current of electricity goes through a wire1 it heats it2 and if the current be made strong enough1 and a white hot wire thus comes in contact with powder or fulminate of mercury in a torpedo1 an explosion will result4 ,but it is important to know exactly when to explode the torpedo1 especially during the night or in a fog2 and hence torpedoes are often made automatic by what is called a circuit closer4 ,this is a device which automatically bridges over the distance between two points which were separated1 thus allowing the current to pass between them4 ,in submarine torpedoes it is usual to employ a small weight1 which1 when the torpedo is struck1 is thrown by the force of the blow across two contact points1 one of which points is in connection with the fuse and the other in connection with the battery1 so that the current immediately runs over the bridge thus offered1 and through the fuse4 ,in practice1 these two contact points are connected by a wire1 even when the torpedo is not in the state of being struck2 but the wire is of such great resistance that the current is too weak to heat the wire in the fuse4 ,yet when the weight above mentioned is thrown across the two contact points1 the current runs across the bridge1 instead of through the resistance wire1 and is then strong enough to heat the wire in the fuse and explode the torpedo4 ,the advantage of having a wire of high resistance between the contact points1 instead of having no wire between them1 is that the current which then passes through the fuse1 though too weak to fire it1 shows by its very existence to the men on shore that the circuit through the torpedo is all right4 ,but instead of having the increased current caused by striking the torpedo to fire the torpedo directly1 a better way is to have it simply make a signal on shore4 ,then1 when friendly vessels are to pass1 the firing battery can be disconnected2 and when the friendly ship bumps the torpedo1 the working of the signal shows not only that the circuit through the fuse is all right1 but also that the circuit closer is all right1 so that1 had the friendly ship been a hostile ship1 she would certainly have been destroyed4 ,while the management of the torpedo is thus simple1 the defense of a harbor becomes a complex problem1 on account of the time and expense required to perfect it1 and the training of a corps of men to operate the torpedoes4 ,in order to detect the presence of torpedoes in an enemy's harbor1 an instrument has been invented by ,capt4 ,mc,evoy1 called the torpedo detecter1 in which the action is somewhat similar to that of the induction balance1 the iron of a torpedo case having the effect of increasing the number of lines of force embraced by one of two opposing coils1 so that the current induced in it overpowers that induced in the other1 and a distinct sound is heard in a telephone receiver in circuit with them4 ,as yet1 this instrument has met with little practical success1 but1 its principle being correct1 we can say with considerable confidence that the reason of its non-success probably is that the coils and current used are both too small4 ,lieut4 ,fiske described the spar torpedo and the various classes of movable torpedoes1 including the ,lay4 ,his conclusion is that the most successful of the movable torpedoes is the ,simms1 with which very promising experiments have been conducted under the superintendence of ,gen4 ,abbot4 ,recent experiments in ,england have shown that the ,whitehead torpedo1 over which control ceases after it is fired1 is not so formidable a weapon when fired at a ship under way as many supposed1 for the simple reason that it can be dodged4 ,but an electrical torpedo1 over which control is exercised while it is in motion through the water1 cannot be dodged1 provided it receives sufficient speed4 ,for effective work against ships capable of steaming fifteen knots per hour1 the torpedo should have a speed of twenty knots4 ,there is no theoretical difficulty in the way of producing this1 for a speed of eleven knots has already been recorded1 though an electric torpedo1 to get this speed1 would have to be larger than a ,whitehead having the same speed4 ,it may be conceived that a torpedo carrying #ej lb4 of gun-cotton1 capable of going #bj knots per hour1 so that it would pass over a distance of #ejj yards in about #de sec41 and yet be absolutely under control all the time1 so that it can be constantly kept pointed at its target1 would be a very unpleasant thing for an enemy to meet4 ,military telegraphy is a second use of electricity in warfare4 ,lieut4 ,fiske traces its origin to our own civil war4 ,foreign nations took the hint from us1 and during the invasion of ,france the telegraph played a most important part4 ,in military telegraph trains1 miles of wire are carried on reels in specially constructed wagons1 which hold also batteries and instruments4 ,some of the wire is insulated1 so that it can rest on the ground1 and thus be laid out with great speed1 while other wire is bare1 and is intended to be put on poles1 trees1 etc4 ,for mountain service the wires and implements are carried by pack animals4 ,regularly trained men are employed1 and are drilled in quickly running lines1 setting up temporary stations1 etc4 ,in the recent ,english operations in ,egypt1 the advance guard always kept in telegraphic communication with headquarters and with ,england1 and after the battle of ,tel-el-,kebir news of the victory was telegraphed to the ,queen and her answer received in forty-five minutes4 ,the telephone is also used with success in warfare1 and in fact sometimes assists the telegraph in cases where1 by reason of the haste with which a line has been run1 the current leaks off4 ,a telephone may then be used to receive the message--and for a transmitter a simple buzzer or automatic circuit breaker1 controlled by an ordinary key4 ,in the case of vessels there is much difficulty in using the telegraph and the telephone1 as the wire may be fouled and broken when the ship swings by a long chain4 ,in ,england in the case of a lightship this difficulty has been surmounted1 or rather avoided1 by making hollow the cable by which the ship rides1 and running an insulated wire along the long tube thus formed inside4 ,but the problem is much simplified when temporary communication only is desired between ships at anchor1 between a ship and the shore1 or even between a ship and a boat which has been sent off on some special service1 such as reconnoitering1 sounding1 etc4 ,in this case portable telephones are used1 in which the wire is so placed on a reel in circuit with the telephone that communication is preserved1 even while the wire is running off the reel4 ,the telegraph and telephone are both coming largely into use in artillery experiments1 for example1 in tracking a vessel as she comes up a channel so that her exact position at each instant may be known1 and in determining the spot of fall of a projectile4 ,in getting the time of flight of projectiles electricity is of value2 by breaking a wire in circuit with a chronograph1 the precise instant of start to within a thousandth of a second being automatically registered4 ,velocimeters are a familiar application of electricity somewhat analogous4 ,in these1 wires are cut by the projectile at different points in its flight1 and the breaking of the electric current causes the appearance of marks on a surface moving along at a known speed4 ,the velocity of the projectile in going from one wire to another can then be found4 ,electricity is also used for firing great guns1 both in ships and forts4 ,in the former1 it eliminates the factor of change produced by the rolling of the ship during the movement of the arm to fire the gun4 ,the touch of a button accomplishes the same thing almost instantaneously4 ,moreover1 an absolutely simultaneous broadside can be delivered by electricity4 ,the officer discharges the guns from a fighting tower1 whither the wires lead1 and the men can at once lie down out of the enemy's machine guns1 as soon as their own guns are ready for discharge4 ,the electric motor will certainly be used very generally for handling ordnance on board ships not very heavily plated with armor1 since a small wire is a much more convenient mode of conveying energy to a motor of any kind1 and is much less liable to injury1 than a comparatively large pipe for conveying steam1 compressed air1 or water under pressure4 ,besides1 the electric motor is the ideal engine for work on shipboard1 by reason of its smooth and silent motion1 its freedom from dirt and grease1 the readiness with which it can be started1 stopped1 and reversed1 and its high efficiency4 ,indeed1 in future we may look to a protected apparatus for all such uses in every fort and every powerful ship4 ,in photographing the bores of great guns1 electric lights are used1 and they make known if the gun is accurately rifled and how it is standing the erosion of the powder gases4 ,in the case of a fort1 electricity can be employed in connection with the instruments used for determining at each instant the position of an approaching vessel or army4 ,whitehead torpedoes are now so arranged that they can be ejected by pressing an electric button4 ,electric lights for vessels are now of recognized importance4 ,at first they were objected to on the ground that if the wire carrying the current should be shot away in action1 the whole ship would be plunged in darkness2 and so it would be in an accident befalling the dynamo that generates the current4 ,the criticism is sensible1 but the answer is that different circuits must be arranged for different parts of the ship1 and the wires carrying the current must be arranged in duplicate4 ,it is also easy to repair a break in a copper wire if shot away4 ,as to the dynamo and engines1 they must be placed below the water line1 under a protective deck1 and this should be provided for in building the vessel4 ,there should be several dynamos and engines4 ,all the dynamos should1 of course1 be of the same electromotive force1 and feed into the same mains1 from which all lamps draw their supply1 and which are fed by feeders from the dynamo at different points1 so that accident to the mains in one part of the ship will affect that part only4 ,but it is the arc light1 used as what is called a search light1 that is most valuable in warfare4 ,lieut4 ,fiske thinks its first use was by the ,french in the siege of ,paris1 to discover the operations of the besiegers4 ,it can be carried by an army in the field1 and used for examining unknown ground at night1 searching for wounded on the battle field1 and so on4 ,on fighting vessels the search light is useful in disclosing the attack of torpedo boats or of hostile ships1 in bringing out clearly the target for guns1 and in puzzling an enemy by involving him successively in dazzling light and total darkness4 ,lieut4 ,fiske suggests that this use would be equally effective in embarrassing troops groping to the attack of a fort at night by sudden alternations of blinding light and paralyzing darkness4 ,there should be four search lights on each side of a ship4 ,as to the power and beauty of the search light1 ,lieut4 ,fiske refers to the magnificent one with which he lighted up ,philadelphia last autumn1 during the electric exhibition in that city4 ,one night he went to the tower of the ,pennsylvania railroad station and watched the light stationed at the ,exhibition building on #cb;d street4 ,the ray of light when turned at right angles to his direction looked like a silver arrow going through the sky2 and when turned on him1 he could read the fine print of a railroad time table at arm's length4 ,flashes from his search light were seen at a distance of thirty miles4 ,in using incandescent lamps for night signaling1 the simplest way is to arrange a keyboard with keys marked with certain numbers1 indicating the number of lamps arranged in a prominent position1 which will burn while that key is being pressed4 ,for example1 suppose the number #ecdh means ,prepare to receive a torpedo attack4 ,press keys #e1 #c1 #d1 #h1 and the lights of lamps #e1 #c1 #d1 #h1 successively blaze out4 ,electrical launches have been used to some extent1 their storage batteries being first charged ashore or on board the ship to which the launch belongs4 ,they have carried hundreds of people1 and have made eight knots an hour4 ,the improvement of storage batteries1 steadily going on1 will eventually cause the electrical launch to replace the steam launch4 ,one of its advantages is in having no noise from an exhaust and no flame flaring above a smoke pipe to betray its presence4 ,in warfare two sets of storage batteries should be provided for launches1 one being recharged while the other is in use4 ,mr4 ,gastine ,trouse has recently invented an electric sight1 a filament of fine wire in a glass tube covered with metal on all sides save at the back4 ,the battery is said to be no larger than a man's finger1 and to be attached to the barrel near the muzzle by simple rubber bands1 so arranged that the act of attaching the battery to the barrel automatically makes connection with the sight2 and so arranged also that the liquid of the battery is out of action except when the musket is brought into a horizontal position for firing4 ,to throw a good light upon the target the same inventor has devised a small electric lamp and projector1 which is placed on the barrel near the muzzle by rubber bands1 the battery being held at the belt of the marksman1 with such connections that the act of pressing the butt of the musket against the shoulder completes the circuit1 and causes the bright cylinder of light to fall on the target1 thus enabling him to get as good a shot as in the day time4 ,search lights and incandescent lights are advantageously used with balloons4 ,in submarine boats electricity will one day be very useful4 ,submarine diving will play a part in future wars1 and the diver's lamp will be electrical4 ,progress has been made also in constructing electrical guns1 in which the cartridge contains a fuse which is ignited by pressing an electric button on the gun4 ,a better aim can be had with it1 when perfected1 than with one fired by a trigger4 ,at present1 according to ,lieut4 ,fiske1 this invention has not reached the practical stage1 and the necessity for a battery to fire a cartridge is decidedly an objection4 ,but the battery is very small1 needs little care1 and will last a long time4 ,the hard pull of the ordinary trigger causes a movement of the barrel except in the hands of the most highly skilled marksmen1 and this hard pull is a necessity1 because the hammer or bolt must have considerable mass in order to strike the primer with sufficient force to explode it4 ,having the mass1 it must have considerable inertia2 hence it needs a deep notch to hold it firm when jarred at full cock1 and this deep notch necessitates a strong pull on the trigger4 ,but with an electric gun the circuit-closing parts are very small and light1 and can be put into a recess in the butt of the gun1 out of the way of chance blows4 ,thus a light pressure of the finger is alone needed to fire it1 while from the small inertia of the parts a sudden shock will not cause accidental closing of the circuit and firing of the gun4 99 99 99 99 99 ,,meucci',s ,,claims ,,to ,,the ,,telephone4 ,our readers have already been informed through these columns that1 notwithstanding the refusal of the ,attorney-,general1 ,mr4 ,garland1 to institute suit for the nullification of the ,bell patent1 application has again been made by the ,globe ,telephone ,co41 of this city1 the ,washington ,telephone ,co41 of ,baltimore1 and the ,panelectric ,co4 ,these applications have been referred to the ,interior ,department and ,patent ,office for examination1 and upon their report the institution of the suit depends4 ,the evidence which the companies above mentioned have presented includes not only the statement of ,prof4 ,gray and the circumstances connected with his caveat1 but brings out fully1 for the first time1 the claims of ,antonio ,meucci4 ,illustration3 ,,meucci',s ,,caveat1 #ahga4 ,the latter evidence is intended to show that ,meucci invented the speaking telephone not only before ,bell1 but that he antedated ,reis by several years4 ,in a recent interview with ,meucci we obtained a brief history of his life and of his invention1 which will1 no doubt1 interest our readers4 ,meucci1 a native of ,italy1 was educated in the schools of ,florence1 devoting his time as a student to mechanical engineering4 ,in #ahdd he gave considerable attention to the subject of electricity1 and had a contract with the government of the island of ,cuba to galvanize materials used in the army4 ,while experimenting with electricity he read the works of ,becquerel1 ,mesmer1 and others who treated largely of the virtues of electricity in the cure of disease4 ,meucci made experiments in this direction1 and at one time thought that he heard the sound of a sick person's voice more distinctly than usual1 when he had the spatula connected with the wire and battery in his mouth4 ,illustration3 ,,figs4 #a ,,and #b4--ahdi4 ,the apparatus he used for this purpose is shown in ,fig4 #a4 ,it consists of an oval disk or spatula of copper attached to a wire which was coiled and supported in an insulating handle of cork4 ,to ascertain that he was able to hear the sound1 he covered the device with a funnel of pasteboard1 shown in the adjoining figure1 and held it to his ear1 and thought that he heard the sound more distinctly4 ,these instruments were constructed in #ahdi in ,havana1 where ,meucci was mechanical director of a theater4 ,in ,may1 #ahea1 he came to this country1 and settled in ,staten ,island1 where he has lived ever since4 ,it was not until a year later that he again took up his telephonic studies1 and then he tried an arrangement somewhat different from the first4 ,he used a tin tube1 ,figs4 #c and #d1 and covered it with wire1 the ends of which were soldered to the tongue of copper4 ,with this instrument1 he states1 he frequently conversed with his wife from the basement of his house to the third floor1 where she was confined as an invalid4 ,illustration3 ,,figs4 #c ,,and #d4--aheb4 ,continuing his experiments1 he conceived the idea of using a bobbin of wire with a metallic core1 and the first instrument he constructed on this idea is shown in ,fig4 #e4 ,it consisted of a wooden tube and pasteboard mouth piece1 and supported within the tube was a bundle of steel wires1 surrounded at their upper end by a bobbin of insulated wire4 ,the diaphragm in this instrument1 was an animal membrane1 and it was slit in a semicircle so as to make a flap or valve which responded to the air vibrations4 ,this was the first instrument in which he used a bobbin1 but the articulation naturally left much to be desired1 on account of the use of the animal membrane4 ,meucci fixes the dates from the fact that ,garibaldi lived with him during the years #ahea-ed1 and he remembers explaining the principles of his invention to the ,italian patriot4 ,after constructing the instrument just described1 ,meucci devised another during #ahec-ed4 ,this consisted of a wooden block with a hole in the center which was filled with magnetic iron ore1 and through the center of which a steel wire passed4 ,the magnetic iron ore was surrounded by a coil of insulated copper wire4 ,but an important improvement was introduced here in the shape of an iron diaphragm4 ,with this apparatus greatly improved effects were obtained4 ,illustration3 ,,fig4 #e4--ahec4 ,in #ahef ,meucci first tried1 he says1 a horseshoe magnet1 as shown in ,fig4 #f1 but he went a step backward in using an animal membrane4 ,he states that this form did not talk so well as some which he had made before1 as might be expected4 ,during the years #aheh-fj ,meucci constructed the instrument shown in ,fig4 #g4 ,he here employed a core of tempered steel magnetized1 and surrounded it with a large coil4 ,he used an iron diaphragm1 and obtained such good results that he determined to bring his invention before the public4 ,his national pride prompted him to have the invention first brought out in ,italy1 and he intrusted the matter to a ,mr4 ,bendalari1 an ,italian merchant1 who was about to start for that country4 ,bendalari1 however1 neglected the matter1 and nothing was heard of it from that quarter4 ,at the same time ,meucci described his invention in ,l',eco d',italia1 an ,italian paper published in this city1 and awaited the return of ,bendalari4 ,meucci1 however1 kept at his experiments with the object of improving his telephone1 and several changes of form were the result4 ,fig4 #h shows one of these instruments constructed during #ahfd-fe4 ,it consisted of a ring of iron wound spirally with copper wire1 and from two opposite sides iron wires attached to the core supported an iron button4 ,this was placed opposite an iron diaphragm1 which closed a cavity ending in a mouthpiece4 ,he also constructed the instrument which is shown in ,fig4 #i1 and which1 he says1 was the best instrument he had ever constructed4 ,the bobbin was a large one1 and was placed in a soapbox of boxwood1 with magnet core and iron diaphragm4 ,still seeking greater perfection1 ,meucci1 in #ahfe1 tried the bent horseshoe form1 shown in ,fig4 #aj1 but found it no improvement2 and1 although he experimented up to the year #ahga1 he was not able to obtain any better results than the best of his previous instruments had given4 ,illustration3 ,,fig4 #f4--ahef4 ,when ,meucci arrived in this country1 he had property valued at #bj1jjj1 and he entered into the brewing business and into candle making1 but he gradually lost his money1 until in #ahfh he found himself reduced to little or nothing4 ,to add to his misery1 he had the misfortune of being on the ,staten ,island ferryboat ,westfield when the latter's boiler exploded with such terrible effect in #ahga4 ,he was badly scalded1 and for a time his life was despaired of4 ,after he recovered he found that his wife1 in their poverty1 had sold all his instruments to ,john ,fleming1 a dealer in second-hand articles1 and from whom parts of the instruments have recently been recovered4 ,illustration3 ,,fig4 #g4--aheh-fj4 ,with the view of introducing his invention1 ,meucci now determined to protect it by a patent2 and having lost his instrument1 he had a drawing made according to his sketches by an artist1 ,mr4 ,nestori4 ,this drawing he showed to several friends1 and took them to ,mr4 ,a4 ,bertolino1 who went with him to a patent attorney1 ,mr4 ,t4,d4 ,stetson1 in this city4 ,mr4 ,stetson advised ,meucci to apply for a patent1 but ,meucci1 without funds1 had to content himself with a caveat4 ,to obtain money for the latter he formed a partnership with ,a4,z4 ,grandi1 ,s4,g4,p4 ,buguglio1 and ,ango ,tremeschin4 ,the articles of agreement between them1 made ,dec4 #ab1 #ahga1 credit ,meucci as the inventor of a speaking telegraph1 and the parties agree to furnish him with means to procure patents in this and other countries1 and to organize companies1 etc4 ,the name of the company was ,teletrofono4 ,they gave him #bj with which to procure his caveat1 and that was all the money he ever received from this source4 ,the caveat which ,meucci filed contained the drawing made by ,nestori1 and as shown in the cut1 which is a facsimile1 represents two persons with telephones connected by wires and batteries in circuit4 ,the caveat1 however1 does not describe the invention very clearly2 it describes the two persons as being insulated1 but ,meucci claims that he never made any mention of insulating persons1 but only of insulating the wires4 ,to explain this seeming incongruity1 it must be stated that ,meucci communicated with his attorney through an interpreter1 as he was not master of the ,english language2 and even at the present time he understands and speaks the language very poorly1 so much so that we found it necessary to communicate with him in ,french during the conversation in which these facts were elicited4 ,illustration3 ,,fig4 #h4--ahfd-fe4 ,in the summer of #ahgb1 after obtaining his caveat1 ,meucci1 accompanied by ,mr4 ,bertolino1 went to see ,mr4 ,grant1 at that time the ,vice ,president of the ,new ,york ,district ,telegraph ,company1 and he told the latter that he had an invention of sound telegraphs4 ,he explained his inventions and submitted drawings and plans to ,mr4 ,grant1 and requested the privilege of making a test on the wires of the company1 which test if successful would enable him to raise money4 ,mr4 ,grant promised to let him know when he could make the test1 but after nearly two years of waiting and disappointment1 ,mr4 ,grant said that he had lost the drawings2 and although ,meucci then made an instrument like the one shown in ,fig4 #i for the purpose of a test1 ,mr4 ,grant never tried it4 ,meucci claims that he made no secret of his invention1 and as instance cites the fact that in #ahgc a diver by the name of ,william ,carroll1 having heard of it1 came to him and asked him if he could not construct a telephone so that communication could be maintained between a diver and the ship above4 ,meucci set about to construct a marine telephone1 and he showed us the sketch of the instrument in his memorandum book1 which dates from that time and contains a number of other inventions and experiments made by him4 ,illustration3 ,,fig4 #i4--ahfd-fe4 ,illustration3 ,,fig4 #aj4--ahfe4 ,when ,professor ,bell exhibited his inventions at the ,centennial1 ,meucci heard of it1 but his poverty1 he claims1 prevented him from making his protestations of priority effective1 and it was not until comparatively recently that they have been brought out with any prominence4--,the ,electrical ,world4 99 99 99 99 99 ,,an ,,electrical ,,centrifugal ,,machine ,,for ,,laboratories4 ,footnote3 ,paper read before ,section ,b1 ,british ,association1 ,aberdeen meeting4 ,by ,,alexander ,,watt1 ,f4,i4,c41 ,f4,c4,s4 ,the late ,dr4 ,mohr#a of ,bonn1 advocated the use of a centrifugal machine as a means of rapidly drying crystals and crystalline precipitates2 but although they are admirably adapted for that purpose1 centrifugal machines are seldom seen in our chemical laboratories4 ,footnote #a3 ,lehrb4 d4 ,chem4 ,analyt4 ,titrirmethode1 #c;d ed41 #ahgj1 p4 #fhd4 ,the neglect of this valuable addition to our laboratory apparatus is probably owing to the inconvenience involved in driving the machine at a high speed by means of the ordinary hand driving gear1 especially when the rotation has to be maintained for a considerable length of time4 ,it occurred to me1 therefore1 that by attaching the drum or basket of the machine 7or the rotating table of ,mohr's apparatus7 directly to the spindle of an electro-motor1 the difficulty of driving might be got over1 and at the same time a combination of great efficiency would result1 as the electro-motor1 like the centrifugal machine1 is most efficient when run at a high speed4 ,the apparatus shown in the sketch consists essentially of a perforated basket1 ,a1 which is slipped on to a cone attached to the spindle1 ,s1 of an electro-motor1 and held in position by the nut1 ,d4 ,the casing1 ,b1 with its removable cover1 ,c1 serves to receive the liquid driven out of the substance being dried4 ,a flat form of the ordinary ,siemens ,h armature1 ,e1 revolves between the poles1 ,p1 of the electro-magnets1 ,m1 which are connected by means of the base plate1 ,i4 ,the brass cross-bar1 ,g1 carries the top bearing of the spindle1 ,s1 and prevents the magnet poles from being drawn together4 ,illustration ,from four to six cells of a bichromate battery or ,faure secondary battery furnish sufficient power to run the machine at a high speed4 ,an apparatus with a copper basket four inches in diameter has been found extremely useful in the laboratory for drying such substances as granulated sulphate of copper and sulphate of iron and ammonia1 but more especially for drying sugar1 which when crystallized in very small crystals cannot be readily separated from the sirupy mother-liquor by any of the usual laboratory appliances4 ,for drying substances which act on copper the basket may be made of platinum or ebonite2 in the latter case1 owing to the increased size of the perforations1 it may be necessary to line the basket with platinum wire gauze or perforated parchment paper4 99 99 99 99 99 ,,transmission ,,of ,,power ,,by ,,electricity4 ,the experiments of ,m4 ,marcel ,deprez have entered on a decisive phase4 ,the dynamos are completed1 and were put in place on the #bjth ,october1 when ,m4 ,deprez carried out some preliminary tests in the presence of a commission consisting of ,,mm4 ,collignon1 ,inspector-,general des ,ponts et ,chausses2 ,delebecque1 ,ingenieur en ,chef du ,materiel et de la ,traction of the ,northern ,railway of ,france2 ,contanini1 engineer in the same company2 and ,sartaux4 ,the generating dynamos made by ,,mm4 ,breguet1 and the receiving dynamos constructed by ,,mm4 ,mignon and ,rouart1 were during a preliminary trial placed side by side1 one portion of the circuit being very short1 and the other twice the distance between ,la ,chapelle and ,creil1 or seventy miles4 ,in future experiments the two dynamos will be placed in their normal positions at each end of the line4 ,the generating machine is driven by a locomotive engine2 the resistance of its field magnets is #e4fh ohms1 and of the two armatures #cc ohms4 ,the resistance of the two armatures of the receiving machine is #cf4h ohms1 and the resistance of the line is #ig ohms2 the generator and receiver field magnets are excited each by a separate machine4 ,five different trials were made at varying speeds of the driving shaft2 the initial work on this shaft was measured by a dynamometer1 and the available energy of the shaft of the receiving machine was ascertained by a ,prony brake2 the other results of the experiments were deduced from the constants of the machines and from galvanometric measurements4 ,for the first trials the different elements were as follows3 #a4 ,generating dynamos3 ,velocity of shaft #abc revolutions4 ,electromotive force at terminals1 #ccgj4be volts4 total #cfbd4g ,available work at driving shaft4 #dc h4 p4 ,electrical work of generator #cg4ch ,difference absorbed #e4fb #b4 ,line3 ,work absorbed by the line4 #g4ei h4 p4 #c4 ,receiving dynamos3 ,velocity of shaft #aed revolutions4 ,electromotive force at terminals1 #bfaf4be volts4 total #bccf4id ,electrical work of receiver #bd4aj h4 p4 ,available work on shaft #bb4aj ,difference absorbed #b ,the duty obtained would thus be #bb4aj_/dc #ea4c per cent41 if the work absorbed by the exciting machines be not considered4 ,taking this into account1 it would be reduced to #dj per cent4 ,in subsequent experiments the speed of the generator was increased gradually4 ,in the last trial the following were the elements3 #a4 ,generating dynamos3 ,speed of shaft #aij revolutions4 ,electromotive force at terminals #ebca4be volts4 total #edfi4ge ,available work on driving shaft1 #fb h4 p4 ,electrical work on generator #ec4ei ,difference absorbed #h4ea ,work absorbed by armature #b4cc #b4 ,line3 ,work absorbed by conductors #g4ba h4 p4 #c4 ,receiving dynamos3 ,speed of shaft #bdh revolutions4 ,electromotive force at terminals #dejh volts4 ,electromotive force total #dbdb4fg ,electrical work of receiver #da4dd h4 p4 ,work measured on receiver shaft #ce4h ,difference absorbed #e4fd ,duty obtained1 not including exciting machine #eg per cent4 ,duty obtained1 including exciting machine #dh ,during the various experiments the current traversing the line varied from #g4ei amperes to #g4ba amperes4 ,no heating of any kind was observed4 ,m4,j4 ,bertrand1 who communicated a paper to the ,academy of ,sciences on the subject1 commented on the relatively low speeds4 ,it corresponds to a linear displacement of the surface armatures1 in no case exceeding the speed of a locomotive wheel4 ,the tension reached #e1ejj volts41 under very satisfactory mechanical conditions1 and with a current that in no way endangered the line4 ,this first experiment is certainly encouraging1 and it will be followed by others of a more complete and exhaustive character4 ,,mm4 ,de ,rothschild are now embodying a powerful commission of ,french and foreign scientists who will follow the subject carefully1 and report upon it4 ,it may be safely predicted that one result of this action will be the development of a new series of observations of the highest technical interest and value4--,engineering4 99 99 99 99 99 ,,the ,,locked ,,and ,,corded ,,box ,,trick4 ,the trick with the locked and corded box1 ,i believe1 is an old one1 though perhaps not in its present form4 ,in late years it has been revived with improvements1 and popularized by those clever illusionists1 ,messrs4 ,maskelyne ,cook and ,dr4 ,lynn1 at the ,egyptian ,hall4 ,there are several ways of working the trick or1 rather1 of arranging the special bit of mechanism wherein the peculiar features of the box consist4 ,the one ,i am about to describe is1 ,i think1 the best of those ,i am acquainted with1 or at liberty to divulge4 ,indeed1 ,i don't know that any method is better1 and this one has the advantage over most others of allowing the performer to get into as well as out of the box1 without leaving a trace of his means of ingress4 ,it will be seen the box is paneled1 and all the panels look equally firm and fixed4 ,as a matter of fact1 one of the panels is movable1 though the closest scrutiny would fail to discover this if the box and fittings are carefully made and adjusted4 ,fig4 #a shows the general appearance of the box1 of which the back is the same as the front4 ,in the box ,i describe1 the end marked has a movable panel4 ,the size of the box should be regulated by the size of the performer2 but one measuring #c feet #f inches long by #b feet back to front1 and #ba inches high1 exclusive of the lid1 which may be #c inches1 will be of general use4 ,in making the box it is most important that all sides and panels look alike1 and that nothing special in the appearance of the end with the loose panel should attract notice4 ,fig4 #b shows this end with fittings drawn half of full size1 and it will he seen from this that the framing1 ,a1 is #c inches wide by #a inches thick1 and the panel1 ,b1 inch thick4 ,illustration3 ,,fig4 #a4 ,it will be noticed that the top and bottom rails of the frame are rabbeted to receive the panel1 but the sides are grooved1 the groove in front rail being double the depth of the one in the back rail4 ,illustration3 ,,the ,,locked ,,and ,,corded ,,box ,,trick4 ,by ,,david ,b4 ,,adamson4 ,the dotted line1 ,b1 shows the size of the panel2 the dotted line1 ,c1 shows the depth of groove in the front rail4 ,from this it will be clear that the panel is only held in place at the back and front1 and that on sliding it toward the front it will be free out of the groove in the back rail4 ,three sides of it are thus free1 and a little manipulation will allow of its being taken out altogether1 leaving plenty of space for the performer to get out1 presuming him to have been locked inside the box4 ,if the panel were to be finished in this way1 without further fittings1 the secret would soon be discovered2 and ,i now proceed to show how the panel is held in place and firm while under examination4 ,determine the size of screws that are to be used in fixing the brass corner clamps4 ,let us say ,no4 #g is decided on2 and if brass screws are used1 then get a piece of brass1 ,fig4 #d1 the exact diameter of the screw-head1 and a little longer than the thickness of the framing4 ,if iron screws are to be used1 then this piece must be iron4 ,now bore a hole into which this bolt will fit closely1 right through the framing at ,d1 ,fig4 #b4 ,it is most important that the hole should be made close up to the edge of the panel1 ,b1 so that when the bolt is in it firmly holds the panel1 and prevents it moving from back to front in the grooving4 ,now get a piece of sheet brass1 #a_/h inch thick1 and cut it to the shape shown by ,e1 ,fig4 #b4 ,the width of this piece should not be less than #c_/h inch1 and it must be of such length that the end reaches to the middle of the top framing1 as shown at ,l1 ,fig4 #b4 ,this piece of brass is sunk in the top and front framing1 as shown by the dotted lines1 ,g1 in ,figs4 #b and #c1 and also in section in the latter4 ,when the box is open1 the lower or short arm of this lever1 which is shaped as shown full size1 at ,e1 ,fig4 #h1 is kept pressed down on the bolt1 ,d1 as shown by the dotted lines1 ,e1 ,e1 ,e1 ,fig4 #b1 and ,e1 ,fig4 #g1 by of the spring1 ,j1 ,fig4 #b4 ,on the box being closed1 a pin on the under edge of lid goes into the hole1 ,l1 ,fig4 #c1 and presses the end of the lever down in such a way as to raise the claw end of it from ,d4 ,the thick dotted lines1 ,f1 ,f1 ,f1 ,fig4 #b1 show position of lever when box is closed4 ,it will be noted that the bolt1 ,d1 ,fig4 #d1 has a groove cut in it all around1 into which the claw fits4 ,this prevents the bolt being pushed backward or forward when the box is open4 ,the lever must be hung as shown1 ,k1 ,fig4 #b4 ,the exact position of this is immaterial1 but it is as well to have the fulcrum as near the end as may be1 in order that the claw may be raised sufficiently with only a small movement of the short arm of the lever4 ,of course1 the shorter the arm is1 the more accurately the lid and pin must be made to close4 ,if the pin1 pressing short arm down1 be too short1 the pressure will not be enough to release the claw1 and consequently the performer might find himself really unable to get out of the box after it is locked4 ,the end of the lever should be finished with a wood block1 as ,fig4 #f1 larger than the pin on the lid1 as represented by ,l and ,m1 ,fig4 #c4 ,the block may be of other material1 but should be colored the same as the wood the box is made of1 so that1 if any one were to look down on it1 no suspicion would be aroused1 as might be were plain brass used4 ,illustration3 ,,fig #d4 ,illustration3 ,,fig #e4 ,in ,fig4 #e1 ,i show an easy way of hanging the lever4 ,it is simply a piece of wire sharpened and notched1 so as to form several small barbs1 preventing withdrawal4 ,the mode of fixing will be easily understood by reference to ,b and ,c1 ,fig4 #e4 ,some considerable amount of care will have to be bestowed on fitting and adjusting this part of the work1 on which the successful performance of the trick consists1 and before finally fixing up1 it should be ascertained that all the movements work harmoniously4 ,it will be best to cut the groove in which the lever works from below1 and1 after the lever is fixed1 to fill up the space not required by the lever with strips of wood1 ,h1 ,h4 ,if preferred1 the space can be shaped out from the back1 i4e41 the inside of the framing1 and then filled where not required1 but as this1 however neatly done1 would show a joint which might be detected by sharp eyes1 it is better to cut from below1 though more troublesome4 ,the end containing the movable panel being arranged1 make up the rest of the box to it1 taking care to make the rebates of the top and bottom frames to correspond with those of the end4 ,the other panels should not1 however1 depend on the grooves on two sides only1 but at tops and bottoms as well4 ,illustration3 ,,fig4 #f4 ,illustration3 ,,fig4 #g4 ,,fig4 #h4 ,illustration3 ,,fig4 #i4 ,the rebates are to be cut only to have all the framing inside look alike2 and as the panel1 ,b1 is made to fit quite close into the rebate1 it will not be surmised that it is not fitted in the usual way4 ,after the box is made and fitted together1 the clamping must be done4 ,the only necessity for this is in order that the bolt1 ,d1 which we have seen is made on the outside end exactly to match the screws used to fasten the clamps1 should not be conspicuous1 as it would be were it alone4 ,as it is1 it will not be specially observable1 being apparently only one of the screws to fasten the clamps4 ,the clamps may be of thin brass or iron1 shaped as shown at ,fig4 #i4 ,one of the corner holes must be arranged to cover ,d exactly1 and the others regulated to it4 ,let us suppose that ,a1 ,fig4 #i1 is the one through which the bolt goes2 the other corner screw holes must be equally distant from the edges of the clamps4 ,twelve of these clamps will be needed4 ,after they have been screwed on1 put the bolt through1 and let the claw of the lever hold it in place4 ,then mark and cut the bolt flush with the clamp1 making a hollow on the end of it to imitate the screws1 as ,d1 ,fig4 #d4 ,the other end of the bolt should either be made flush with the inside of frame and colored to match it1 or1 better1 cut short and faced flush with a piece of wood to match the framing4 ,if a piece of wood with a knot be chosen for this side of the frame1 so much the better4 ,immediately over the hole1 ,l1 a wooden pin should be fixed in the lid1 and of such length that it will press the short arm of lever down sufficiently4 ,it should fit the hole pretty closely4 ,at the other end1 a corresponding pin and hole should be made1 and1 say1 two along the front4 ,these will then look as if they were intended merely as fittings to hold the lid in position4 ,the lid at the other end of the box from the movable panel should have a stop of some sort2 the ordinary brass joint stop will do as well as any1 and should be strong4 ,the reason for placing it at what ,i may call the other end is that1 when the box is being examined1 it will attract notice1 and draw attention from the movable panel end4 ,we may now finally adjust the loose panel1 which must fit tight at top and bottom1 and be slightly beveled1 as shown on section4 ,two holes must also be cut through it1 at such a distance from each other that a finger and thumb can be put through them1 so as to allow of the panel being moved4 ,in the deep grooving in front also put a couple of springs1 say pieces of clock springs1 as shown1 ,i1 ,i1 ,fig1 #b4 ,these serve to assist the bolt1 ,d1 by pushing the panel into position4 ,holes to match those in end panel must also be cut in the other panels1 and when a lock1 preferably a padlock1 has been fitted1 the box is complete4 ,i don't know whether it is necessary to say that the lid should be hinged at the back1 and of course it will add to the appearance of the box if it be polished or oiled4 ,now1 for those who may not have seen the locked and corded box trick performed1 a few words of caution may not be out of place4 ,don't forget to have something in a pocket easily got at that will serve to push the bolt out1 before going into the box4 ,a piece of stout wire1 a small pencil case1 or anything of that sort will do4 ,be careful when getting into the box to lie with your head toward the loose panel end1 and face toward the front--as there will be no space to turn round2 the right hand will then be uppermost and free to push the bolt out4 ,having done this1 grasp the panel with the finger and thumb by means of the two holes1 push it to the front of the box1 when the back edge will be clear of the groove4 ,it can now easily be pulled into the box1 and the performer can creep out4 ,when out1 refix panel and bolt so that everything looks as it was4 ,any cording that may be over the end of the box will give sufficiently to allow of exit4 ,i have1 ,i think1 made it quite clear that padlock and ropes have nothing to do with the real performance of the trick1 but they serve to mystify spectators1 who may be allowed to knot the rope and seal the knots in any way they choose4 ,there must always be a screen or curtain to hide the box from the spectators while the performer is getting in or out4--,d4,b4 ,adamson1 in ,amateur ,work4 99 99 99 99 99 ,,prices ,,of ,,metals4 ,the ,metallarbeiter remarks that metals have in most cases experienced a reduction in value of late years1 this depreciation being attributed in some measure to the cheaper methods of obtaining metals as well as to the discovery of new sources of mineral wealth4 ,the following comparative table shows the approximate prices of various metals in ,december1 #ahgd1 and ,december1 #ahhd3 ,dec41 #ahgd4 ,dec41 #ahhd4 ,per lb4 ,per lb4 s d4 s4 d4 ,osmium #ga #aj #j #fb #j #j ,iridium #gj #j #j #de #j #j ,gold #fb #ae #j #fc #j #j ,platinum #be #g #f #ba #g #f ,thallium #bc #ag #f #d #ae #j ,magnesium #aj #e #j #a #ae #j ,potassium #e #j #j #d #j #j ,silver #c #ag #f 7in ,hamburg7 #c #g #f ,aluminum #a #af #j #a #af #j ,cobalt #a #ad #j #a #b #j ,sodium #j #ad #b #j #h #h ,nickel #j #aa #j #j #c #a ,bismuth #j #h #a #j #h #a ,cadmium #j #g #a #j #d #j ,quicksilver #j #b #j 7in ,london7 #j #a #i ,tin #j #a #a 7in ,berlin7 #j #j #i ,copper #j #j #aj 7 7 #j #j #g ,arsenic #j #j #h #j #j #d-a_/b ,antimony #j #j #f-a_/d 7 7 #j #j #e ,lead #j #j #b-c_/d 7 7 #j #j #a-c_/h ,zinc #j #j #b-a_/b 7 7 #j #j #a-c_/d ,steel #j #j #a-c_/h 7 in #j #j #j-c_/d ,bar iron #j #j #a-a_/h ,upper #j #j #j-e_/h ,pig iron #j #j #j-g_/af ,silesia 7 #j #j #j-a_/d ,gold now ranks highest in value of all metals1 the competition of osmium and iridium having been over come4 ,it is only by reason of improved methods of preparation that the latter have become cheaper1 while their use has at the same time increased4 ,iridium is mixed with platinum in order to increase its strength and durability4 ,the normal standards of the metrical system are made of platinum-iridium on account of its known immutabilty4 ,in #ahhb1 platinum stood #ae per cent4 below its present value2 but its increased employment for industrial purposes led to the subsequent improvement in price4 ,thallium has experienced a severe depreciation on account of the economical process by which it is extracted from the residue of the lead chambers used in the manufacture of sulphuric acid4 ,the use of this metal is mainly confined to experimental purposes4 ,the fall in silver has arisen from increased production and diminished use for coinage4 ,magnesium was scarcely of any industrial value prior to the fall in price now recorded4 ,improved processes for its treatment have successfully engaged the attention of scientific men1 and it is now capable of being used as an alloy with other metals4 ,the ,salindres factory regulates the price to a certain extent1 and its system of working is regarded as a guide in the various processes connected with this branch of industry4 ,the manufacture of potassium and sodium will1 it is expected1 be more fully elucidated than hitherto1 by means of researches made at ,schering's ,charlottenburg factory4 ,the course of nickel prices illustrates the stimulus to economical production afforded by an increased consumption4 ,this latter fact is principally due to the employment of nickel for coinage1 as alloy for alfenide1 etc4 ,the use of cadmium is materially restricted by its relatively limited supply4 ,hitherto1 its only source was in the incidental products of zinc distillation1 but of late it has been attempted to bring it into solution from its oxide combinations4 ,an increased employment of cadmium for industrial purposes is expected to follow4 ,production in excess of the demand has caused the depreciation recorded in tin1 and various other metals not commented upon1 this remark applying even to the scarce metals1 arsenic and antimony4 ,even the better marks of ,cornwall tin and ,mansfield refined copper have had to follow the downward course of the market4 99 99 99 99 99 ,a ,,perpetual ,,calendar4 ,the annexed figure represents a perpetual calendar1 which any one can construct for himself1 and which permits of finding the day that corresponds to a given date1 and conversely4 ,the apparatus consists of a certain number of circles and arcs of circles divided by radii4 ,the ring formed by the two last internal circles is divided into #bh equal parts1 which bear the names of the week1 the first seven letters of the alphabet in reversed order1 and two signs ,x4 ,the circle formed by the external circumference of the ring constitutes the movable part of the apparatus1 and revolves around its center4 ,two circular sectors1 which are diametrically opposite1 are each divided into seven parts and constitute the fixed portions4 ,in the divisions of the upper sector are distributed the months1 according to the order of the monthly numbers4 ,in the other sector the days of the month are regularly distributed4 ,in order to render the affair complete1 a table is arranged upon the movable disk for giving the annual numbers1 or rather1 in this case1 the annual letters4 ,the calendar is used as follows3 ,say1 for example1 we wish to find what days correspond to the different dates of ,august1 #ahhe2 we look in the table for the letter 7,d7 that corresponds to this year2 then we bring this letter under the given month 7,august7 and the days marked upon the movable disk corresponding to the dates sought1 and it only remains to make a simple reading4 ,illustration3 ,,perpetual ,,calendar4 ,it will be seen that the leap-years correspond to two letters4 ,we here employ the first to ,feb4 #bi inclusive1 and the second for the balance of the year4 ,the calendar may be made of cardboard1 and be fixed to wood4--,la ,nature4 99 99 99 99 99 ,,an ,,accomplished ,,parrot4 ,around the door of a ,sixth ,ave4 bird store near ,twenty-third ,st4 was gathered the other day a crowd so large that it was a work of several minutes to gain entrance to the interior4 ,from within there proceeded a hoarse voice dashed with a suspicion of whisky1 which bellowed in ,irish-,american brogue the enlivening strains of ,peek-a-boo4 ,with each reiteration of ,peek-a-boo the crowd hallooed with delight1 and one small boy1 in the exuberance of his joy1 tied himself into a sort of knot and rolled on the pavement4 ,suddenly the inebriated ,irishman came to a dead stop1 and another voice1 pleasanter in quality1 sang the inspiring national ode of ,yankee ,doodle1 followed by the stentorian query and answer all in one1 ,how are the ,psi-,upsilon boys8 ,oh1 they're all right6 ,a passer-by1 puzzled at the scene1 made his way into the store and soon solved the mystery4 ,in a large cage in the center was an enormous green and yellow parrot1 which was hanging by one foot to a swinging perch1 and trolling forth in different voices with the ease of an accomplished ventriloquist4 ,he resumed a normal position as he was approached1 and flapping his wings bellowed out1 ,hurrah for ,elaine and ,logan6 ,then1 cocking his head on one side1 he dropped into a more conversational tone1 and with a regular ,alice in ,wonderland air remarked3 ,it's never too late to mend a bird in the hand2 and again1 after a pause1 ,it's a long lane that never won fair lady4 ,his visitor affably remarked3 ,you're quite an accomplished bird1 ,polly1 and quick as a flash the creature replied3 ,i can spell1 ,i can4 ,c-a-t1 cat4 ,d-o-g1 fox1 with an affectation of juvenility which was grewsome4 ,he resented an ill-advised attempt at familiarity by snapping at the finger which tried to scratch his poll1 and barked out3 ,take care6 ,i'm a bad bird1 ,i am4 ,you betcher life6 ,he's one of the cleverest parrots ,i have had for some time1 said his owner1 ,mr4 ,holden4 ,in fact1 he is almost as good as ,ben ,butler1 whom ,i sold to ,patti4 ,his stock of proverbs seems inexhaustible1 and he makes them quite funny by the ingenious way in which he mixes them up4 ,i could not begin to tell you all the things he says1 but his greatest accomplishment is his singing4 ,he is a double yellowhead--the only species of parrot which does sing4 ,the ,african grays are better talkers1 but they do not sing4 ,they only whistle4 ,what do ,i ask for him8 ,oh1 ,i think #bjj is cheap for such a paragon1 don't you8--,n4,y4 ,tribune4 99 99 99 99 99 ,,the ,,roscoff ,,zoological ,,laboratory4 ,the celebrated ,roscoff zoological station was founded in #ahgb1 and has therefore been in existence for thirteen years2 but it may be said that it has changed appearance thirteen times4 ,those who1 for the last six or seven years1 have gone thither to work with diligence find at every recurring season some improvement or new progress4 ,a rented house1 a small shed in a yard1 little or no apparatus1 and four work rooms--such was the debut of the station2 and modest it was1 as may be seen4 ,later on1 the introduction of a temporary aquarium1 which1 without being ornamental1 was not lacking in convenience1 sufficed for making some fine discoveries regarding numerous animals4 ,a small boat served for supplying necessaries to the few workers who were then visiting ,roscoff2 but as the number of these kept gradually increasing1 it became necessary to think of enlarging the station1 and the purchase of a piece of property was decided upon4 ,since then1 ,mr4 ,lacaze ,duthiers has done nothing but develop and transform this first acquisition4 ,a large house1 which was fitted up in #ahgi1 formed the new laboratory4 ,this was built in a large garden situated nearly at the edge of the sea4 ,we say nearly1 as the garden in fact was separated from the sea by a small road4 ,the plan in ,fig4 #a shows that this road makes an angle2 but formerly it was straight1 and passed over the terrace which now borders upon the fish pond4 ,how many measures1 voyages1 and endless discussions1 and how much paper and ink1 it has taken to get this road ceded to the laboratory6 ,finally1 after months of contest1 victory rewarded ,mr4 ,duthiers's tenacity1 and he was then able to begin the construction of a pond and aquarium4 ,all this was not done at once4 ,illustration3 ,,fig4 #a4--,,plan ,,of ,,the ,,roscoff ,,laboratory4 ,another capital improvement was made in #ahhb4 ,the public school adjoining the establishment was ceded to it1 the separating walls fell1 the school became a laboratory1 the class rooms were replaced by halls for research1 and now no trace of the former separation can be seen--so uniform a whole does the laboratory form4 ,no one knows what patience it required to form1 piecemeal as it were1 so vast an establishment1 and one whose every part so completely harmonizes4 ,during the same year a park1 one acre in area1 was laid out on the beach opposite the laboratory4 ,this is daily covered by the sea1 and forms a preserve in which animals multiply1 and which1 during the inclement season1 when distant excursions are impossible1 permits of satisfying the demands that come from every quarter4 ,all1 however1 is not finished4 ,last year a small piece of land was purchased for the installation of hydraulic apparatus for filling the aquarium4 ,this acquisition was likewise indispensable1 in order to prevent buildings from being erected upon the land and shutting off the light from the work rooms opposite4 ,alas1 here we find our enemy again--the little road6 ,negotiations have been going on for eighteen months with the common council1 and1 what is worse1 with the army engineers1 concerning the cession of this wretched footpath4 ,the reader now knows the principal phases of the increases and improvements through which the ,roscoff station has passed4 ,if1 with the plan before his eyes1 he will follow us1 we will together visit the various parts of the laboratory4 ,the principal entrance is situated upon the city square1 one of the sides of which is formed by the buildings of the station4 ,we first enter a large and beautiful garden ornamented with large trees and magnificent flowers which the mild and damp climate of ,roscoff makes bloom in profusion4 ,we next enter a work room which is designed for those pupils who1 doing no special work1 come to ,roscoff in order to study from nature what has been taught them theoretically in the lecture courses of schools1 etc4 ,there is room here for nine pupils1 to each of whom the laboratory offers two tables1 with tanks1 bowls1 reagents1 microscopes1 and instruments of all kinds for cabinet study1 as well as for researches upon animals on the beach4 ,here the pupils are in presence of each other1 and so the explanations given by the laboratory assistants are taken advantage of by all4 ,at the end of this room1 on turning to the left1 we find two large apartments--the library and museum4 ,here have been gradually collected together the principal works concerning the fauna of ,roscoff and the ,english ,channel1 maps and plans useful for consultation1 numerous memoirs1 and a small literary library4 ,the scientific collection contains the greater portion of the animals that inhabit the vicinity of ,roscoff4 ,to every specimen is affixed a label giving a host of data concerning the habits1 method of capture1 and the various biological conditions special to it4 ,in a few years1 when the data thus accumulated every season by naturalists have been brought together1 we shall have a most valuable collection of facts concerning the fauna of the coast of ,france4 ,two store rooms at the end of these apartments occupy the center of the laboratory1 and are thus more easy of access from the work rooms1 and the objects that each one desires can be quickly got for him4 ,illustration3 ,,fig4 #b4--;,,interior ,,of ,,one ,,of ,,the ,,stalls ,,for ,,study4 ,after the store rooms comes what was formerly the class room for boys1 and which has space for three workers1 and then the former girls' class room1 which has space for eight more4 ,let us stop for a moment in this large room1 which is divided up into eight stalls1 each of which is put at the disposal of some naturalist who is making original researches4 ,fig4 #b represents one of these1 and all the rest are like it4 ,three tables are provided1 the space between which is occupied by the worker4 ,of these1 one is reserved for the tanks that contain the animals1 another1 placed opposite a window giving a good light1 supports the optical apparatus1 and the last is occupied by delicate objects1 drawings1 notes1 etc41 and is1 after a manner1 the worker's desk4 ,some shelving1 some pegs1 and a small cupboard complete the stall4 ,it is unnecessary to say that the laboratory furnishes gratuitously to those who are making researches everything that can be of service to them4 ,four of these stalls are situated to the north1 with a view of the sea1 and the other four overlook the garden4 ,they are separated from each other by a simple partition1 and all open on a wide central corridor that leads to the aquarium4 ,before reaching the latter we find two offices that face each other1 one of them for the lecturer and the other for the preparator4 ,these rooms1 as far as their arrangement is concerned1 are identical with the stalls of the workers4 ,the laboratory1 then1 is capable of receiving twenty-three workers at a time1 and of offering them every facility for researches4 ,illustration3 ,,fig4 #c4--;,,general ,,view ,,of ,,the ,,roscoff ,,laboratory4 ,the aquarium is an immense room1 #ih ft4 in length by #cc in width1 glazed at the two sides4 ,it is at present occupied only by temporary tanks that are to be replaced before long by twenty large ones of #acj gallons capacity1 and two oval basins of from #fej to #hge gallons capacity1 constructed after the model of the one that is giving so good results at ,banyuls4 ,at the extremity of the aquarium there is a store room containing trawls1 nets of all kinds1 and mops1 for the capture of animals4 ,here too is kept the rigging of the two laboratory boats1 the ,dentale and ,laura4 ,above the store room is located the director's work room4 ,a wide terrace separates the aquarium from the pond4 ,this latter is #ch yards long by #ce wide4 ,thanks to a system of sluice valves1 it is filled during high tide1 and the water is shut in at low tide1 thus permitting of having a supply of living animals in boxes and baskets until the resources of the laboratory permit of a more improved arrangement4 ,this basin is shown in ,fig4 #c4 ,it is at the north side of the laboratory as seen from the beach4 ,here too we see the aquarium1 the garden1 and a portion of the shore that serves as a post for the station boats4 ,we must not1 in passing1 fail to mention the extreme convenience that the proximity of the aquarium work room to the pond and sea offers to the student4 ,this entire collection of halls1 constituting the scientific portion of the laboratory1 occupies the ground floor4 ,the first and second stories are occupied by sleeping apartments1 fourteen in number4 ,these1 without being luxurious1 are sufficiently comfortable1 and offer the great advantage that they are very near the work rooms1 thus permitting of observing1 at leisure1 and at any hour of the day or night1 the animals under study4 ,everything is absolutely free at the laboratory4 ,the work rooms1 instruments1 reagents1 boats1 dwelling apartments1 etc41 are put at the disposal of all with an equal liberality2 and this absence of distinction between rich or poor1 ,frenchmen or foreigners1 is the source of a charming cordiality and good will among the workers4 ,shall we speak1 too1 of the richness of the ,roscoff fauna8 ,this has become proverbial among zoologists1 as can be attested by the #bfe of them who have worked at the laboratory4 ,the very numerous and remarkable memoirs that have been prepared here are to be found recorded in the fourteen volumes of the ,archives de ,zoologie ,experimentale founded by ,mr4 ,lacaze ,duthiers4 ,it only remains to express our hope that the aquarium may be soon finished2 but before this is done it will be necessary to get possession of that unfortunate little road4 ,after this final victory1 ,mr4 ,duthiers in his turn will be able1 amid his pupils1 to enjoy all those advantages of his work which he has until now offered to others1 but from which he himself has gained no benefit4--,la ,nature4 99 99 99 99 99 ,,the ,,mur,n ,,at ,,the ,,berlin ,,aquarium4 ,of all fish1 eels are probably the most interesting1 as the least is known of them4 ,electricians are now examining the animal source of electricity in the electric eel 7,gymnotus electricus72 zoologists are still searching for the solution of the problem of the generation of eels1 of which no more is known than that the young eels are not born alive2 and numerous fishing societies are now studying the important question of raising eels in ponds1 lakes1 etc41 that are not connected with the sea4 ,illustration3 ,,the ,,mur,n ,,at ,,the ,,berlin ,,aquarium4 ,the annexed cut1 taken from the ,illustrirte ,zeitung1 is a copy of a drawing by ,muetzel1 and represents a group of ,mediterranean ,murn 7,murna ,helena74 ,this fish attains a length of from #e ft4 to #f ft41 and has a smooth1 scaleless body of a dark color1 on which large light-yellow spots appear1 which give the fish a very peculiar appearance4 ,the pectoral fin is missing1 but it has the dorsal and anal fins1 which it uses with great ability4 ,its head is pointed1 and its jaws are provided with extraordinarily sharp teeth1 which are inclined toward the rear2 and at each side of the head it is provided with a gill4 ,the nostrils are on the upper side of the snout1 and a second1 tubular1 pair of nostrils is located near the eyes4 ,the bright eyes have a fierce expression1 which makes the fish appear very much like a snake4 ,these fish are ravenous1 and devour crabs1 snails1 worms1 and fishes1 and if they have no other food1 bite off the tails of their brethren4 ,they are caught in eel baskets or cages1 and by means of hooks2 but they are rather dangerous to handle1 as they attack the fishermen and injure them severely4 ,since the times of the ancients1 ,murn have been prized very highly on account of their savory flesh4 ,the ,romans were great experts at feeding these fish1 ,vidius ,pollio being the master of them all1 as he made a practice of feeding his ,murn with the flesh of slaves sentenced to death4 ,pliny states that at ,csar's triumphal entry ,hirius furnished six thousand ,murn4 ,slaves were frequently driven into the ponds1 and were immediately attacked by the voracious fishes1 and killed in a very short time4 99 99 99 99 99 ,,metamorphoses ,,of ,,arctic ,,insects4 ,in the chapter entitled ,das insektenleben in arktischen lndern1 which ,dr4 ,christopher ,aurivillius contributes to the account of ,a4,e4 ,nordenskild's ,arctic investigations1 published this year in ,leipzig1#b the author says3 ,the question of the mode of life of insects and of its relation to their environment in the extreme north is one of especial interest4 ,knowing1 as we do1 that any insect in the extreme north has at the most not more than from four to six weeks in each year for its development1 we wonder how certain species can pass through their metamorphosis in so short a period4 ,r4 ,mc,lachlan adverts1 in his work upon the insects of ,grinnell ,land1 to the difficulties which the shortness of the summer appears to put in the way of the development of the insects1 and expresses the belief that the metamorphosis which we are accustomed here to see passed through in one summer there requires several summers4 ,the correctness of this supposition has been completely shown by the interesting observations which ,g4 ,sandberg has made upon species of lepidoptera in ,south ,varanger1 at #fi #dj' north latitude4 ,sandberg succeeded in following the development from the egg onward of some species of the extreme north4 ,oeneis bore1 ,schn41 a purely ,arctic butterfly1 may be taken as an example4 ,this species has never been found outside of ,arctic regions1 and even there occurs only in places of purely ,arctic stamp4 ,it flies from the middle of ,june onward1 and lays its eggs on different species of grass4 ,the eggs hatch the same summer2 the larva hibernates under ground1 continues eating and growing the next summer1 and does not even then reach its full development1 but winters a second time and pupates the following spring4 ,the pupa1 which in closely related forms1 in regions further to the south1 is suspended free in the air upon a blade of grass or like object1 is in this case made in the ground1 which must be a very advantageous habit is so raw a climate4 ,the imago leaves the pupa after from five or six weeks1 an uncommonly long period for a butterfly4 ,in more southern regions the butterfly pupa rests not more than fourteen days in summer4 ,the entire development1 then1 takes place much more slowly than it does in regions further south4 ,sandberg has shown1 then1 by this and other observations1 that the ,arctic summer1 even at #gj ,n41 is not sufficient for the development of many butterflies1 but that they make use of two or more summers for it4 ,if then more than one summer is requisite for the metamorphosis of the butterflies1 it appears to me still more likely that the humble-bees need more than one summer for their metamorphosis4 ,with us only the developed female lives over from one year to the next2 in spring she builds the new nest1 lays eggs1 and rears the larv which develop into the workers1 who immediately begin to help in the support of the family2 finally1 toward autumn1 males and females are developed4 ,it seems scarcely credible that all this can take place each summer in the same way in ,grinnell ,land1 at #hb ,n41 especially as the access to food must be more limited than it is with us4 ,the development of the humble-bee colony must surely be quite different there4 ,if it is not surely proved that the humble-bees occur at so high latitudes1 one would not1 with a knowledge of their mode of life1 be inclined to believe that they could live under such conditions4 ,they seem1 however1 to have one advantage over their relatives in the south4 ,in the ,arctic regions none of those parasites are found which in other regions lessen their numbers1 such as the conopid among the flies1 the mutillas among the hymenoptera1 and others4--,psyche4 ,footnote #b3 ,nordenskild1 ,a4,e41 ,studien und forschungen veranlasst durch meine reisen im hohen norden4 ,autorisirte ausgabe4 ,leipzig1 ,brockhaus1 #ahhe1 #i #eha pp41 #h pl41 maps1 ,o4 il4 99 99 99 99 99 ,a ,,year',s ,,scientific ,,progress ,,in ,,nervous ,,and ,,mental ,,diseases4 ,footnote3 ,volunteer report presented to ,nebraska ,state ,medical ,society1 ,may1 #ahhe1 at ,grand ,island1 ,neb4 ,by ,l4,a4 ,,merriam1 ,m4,d41 ,omaha1 ,neb41 ,professor of the ,principles and ,practice of ,medicine in the ,university of ,nebraska ,college of ,medicine1 ,lincoln1 ,neb4 ,the records of the ,nebraska ,state ,medical ,society show that the only report of progress on nervous and mental diseases ever made in the history of the society 7sixteen years7 was made by the writer last year2 and expecting that those appointed to make a report this year would1 judging by the history of the past1 fail to prepare such a report1 ,i have seen fit to prepare a brief volunteer report of such items of progress as have come to my notice during the last twelve months4 ,i have not been able to learn that any original work has been done in our ,state during the past year1 nor that those having charge of the insane hospital have utilized the material at their command to add to the sum of our knowledge of mental diseases4 ,last year ,i said3 ,there is a growing sentiment that many diseases not heretofore regarded as nervous 7and perhaps all diseases7 are of nervous origin4 ,this truth1 that all pathologico-histological changes in the tissues of the body are degenerative in character1 and1 whether caused by a parasite1 a poison1 or some unknown influence1 are first brought about by or through a changed innervation1 is one that is being accepted very largely by the best men in the profession1 and the accumulation of facts is increasing rapidly1 and the acceptance of this great truth will prove to be little short of revolutionary in its influence on the treatment of the disease4 ,this is the outgrowth of the study of disease from the standpoint of the evolution hypothesis4 ,derangements of function precede abnormalities of structure2 hence the innervation must be at fault before the organ fails4 ,hence the art of healing should aim at grappling with the neuroses first1 for the local trophic changes1 perverted secretions1 and structural abnormalities are the effects or symptoms1 not the causes of the disease4 ,dr4 ,j4,l4 ,thudicum has studied the chemical constitution of the brain1 and he holds that1 ,when the normal composition of the brain shall be known to the uttermost item1 then pathology can begin its search for abnormal compounds or derangements of quantities4 ,the great diseases of the brain and spine1 such as general paralysis1 acute and chronic mania1 and others1 the author believes will all be shown to be connected with special chemical changes in neuroplasm1 and that a knowledge of the composition and properties of this tissue and of its constituents will materially aid in devising modes of radical treatment in cases in which1 at present1 only tentative symptomatic measures are taken4 ,the whole drift of recent brain inquiry sets toward the notion that the brain always acts as a whole1 and that no part of it can be discharging without altering the tensions of all the other parts2 for an identical feeling cannot recur1 for it would have to recur in an unmodified brain1 which is an impossibility1 since the structure of the brain itself is continually growing different under the pressure of experience4 ,insanity is a disease of the most highly differentiated parts of the nervous system1 in which the psychical functions1 as thought1 feeling1 and volition1 are seriously impaired1 revealing itself in a series of mental phenomena4 ,institutions for the insane were at first founded for public relief1 and not to benefit the insane2 but this idea has changed in the past1 and there is a growing feeling that a natural and domestic abode1 adapted to the varying severity of the different degrees of insanity1 should be the place for the insane1 with some reference to their wants and necessities1 and that many patients 7not all7 could be better treated in a domestic or segregate asylum than in the prison-like structures that so often exist1 and that the asylum should be as much house-like and home-like in character as the nature of the insanity would permit2 while exercise and feeding are accounted as among the best remedies in some cases of insanity1 particularly in acute mania4 ,the new disease called morbus ,thomsenii1 of which ,i wrote in my report last year1 has been carefully studied by several men of eminence1 and the following conclusions have been reached as to its pathology3 ,the weight of the evidence seems to prove that it is of a neuropathic rather than a myopathic nature1 and that it depends on an exaggerated activity of the nervous apparatus which produces muscular tone1 and that it has much analogy to the muscular phenomena of hysterical hypnosis1 the genesis of which is precisely explained by a functional hyperactivity of the nervous centers of muscular activity4 ,until quite recently it was supposed that the rhythmical action of the heart was entirely due to the periodical and orderly discharge of motor nerve force in the nerve ganglia which are scattered through the organ2 but recent physiological observations1 more especially the brilliant researches of ,graskell1 seem to show that the influence of the cardiac ganglia is not indispensable1 and that the muscular fiber itself1 in some of the lower animals1 at all events possesses the power of rhythmical contraction4 ,several valuable additions to our knowledge of the anatomy of the nervous system have been made by ,huschke1 ,exner1 ,fuchs1 and ,tuczek4 ,tuczek and ,fuchs have confirmed the discoveries of ,exner1 that there are no medullated nerve fibers in the convolutions of the infant1 and ,flechzig has developed this law1 that medullated nerve fibers appear first in the region of the pyramidal tracts and corona radiata1 and extend from them to the convolutions and periphery of the brain1 being practically completed about the eighth year4 ,this fact is of practical importance in nervous and mental diseases1 since it is becoming an admitted truth that the histological changes in disease follow in an inverse order the developmental processes taking place in the embryo4 ,hence the recent physiological division of the nervous system by ,dr4 ,hughlings ,jackson into highest1 middle1 and lowest centers1 and the evolution of the cerebro-spinal functions from the most automatic to the least automatic1 from the most simple to the most complex1 from the most organized to the least organized4 ,in the recognition of this division we have the promise of a steadier and more scientific advance1 both in the physiology and in the pathology of the nervous system4 ,mr4 ,victor ,horsley has recently demonstrated the existence of true sensory nerves supplying the nerve trunks of nervi-nervorum4 ,prof4 ,hamilton1 of ,aberdeen1 claims that the corpus callosum is not a commissure1 but the decussation of cortical fibers on their way down to enter the internal and external capsules of the opposite side4 ,profs4 ,burt ,g4 ,wilder1 of ,ithaca1 and ,t4 ,jefrie ,parker1 of ,new ,zealand ,institute1 have proposed a new nomenclature for macroscopic encephalic anatomy1 which1 while seemingly imperfect in many respects1 has1 at least1 the merit of stimulating thought1 and has given an impulse to a reform which will not cease until something has been actually accomplished in this direction4 ,the object being to substitute for many of the polynomial terms1 technical and vernacular1 now in use1 technical names which are brief and consist of a single word4 ,this has already been adopted by several neurologists1 of whom we may mention ,spitzka1 ,ramsey1 ,wright1 and ,h4,t4 ,osborn4 ,luys holds that the brain1 as a whole1 changes its position in the cranial cavity according to different attitudes of the body1 the free spaces on the upper side being occupied by cerebro-spinal fluid1 which1 obeying the laws of gravity1 is displaced by the heavier brain substance in different positions of the body4 ,luys claims that momentary vertigo1 often produced by changing from a horizontal to a vertical position1 seasickness1 pain in movement in cases of meningitis1 epileptic attacks at night1 etc41 may be by this explained4 ,these views of ,luys are accepted as true1 but to a less extent than taught by ,luys4 ,the prevalent idea that a lesion of one hemisphere produces a paralysis upon the opposite side of the body alone is no longer tenable1 for each hemisphere is connected with both sides of the body by motor tracts1 the larger of the motor tracts decussating and the smaller not decussating in the medulla4 ,hence a lesion of one hemisphere produces paralysis upon the opposite side of the body4 ,it has recently been established that a lesion of one hemisphere in the visual area produces1 not blindness in the opposite eye1 as was formerly supposed1 but a certain degree of blindness in both eyes1 that in the opposite eye being greater in extent than that in the eye of the same side4 ,analogy would indicate that other sensations follow the same law1 hence the probability is that all the sensations from one side of the body do not pass to the parietal cortex of the opposite side1 but that1 while the majority so pass1 a portion go up to the cortex of the same side from which they come4 ,dr4 ,hammond says that the chief feature of the new ,siberian disease called miryachit is1 that the victims are obliged to mimic and execute movements that they see in others1 and which motions they are ordered to execute4 ,dr4 ,beard1 in ,june1 #ahhj1 observed the same condition when traveling among the ,maine hunters1 near ,moosehead ,lake4 ,these men are called jumpers1 or jumping ,frenchmen4 ,those subject to it start when any sudden noise reaches the ears4 ,it appears to be due to the fact that motor impulse is excited by perceptions without the necessary concurrence of the volition of the individual to cause the discharge1 and are analogous to epileptiform paroxysms due to reflex action4 ,the term spiritualism has come to signify more than has usually been ascribed to it1 for some recent authors are now using the term to denote a neurosis or nervous affection peculiar to that class of people who claim to be able to commune with the spirits of the dead4 ,evidence obtained from clinical observations has tended of late to locate the pathological lesions of chorea in the cerebral cortex4 ,dr4 ,godlee's operation of removing a tumor from the brain marks an important step in cerebral localization1 and cerebral surgery bids fair to take a prominent place in the treatment of mental diseases4 ,wernicke has observed that the size of the occipital lobes is in proportion to the size of the optic tracts1 and that the occipital lobes are the centers of vision4 ,hughlings ,jackson has observed that limited and general convulsions were often produced by disease in the cortex of the so-called motor convolutions4 ,the sense of smell has been localized by ,munk in the gyri hippocampi1 while the center of hearing has been demonstrated to be in the temporal lobes4 ,the center for the muscles of the face and tongue is in the inferior part of the central convolution2 that for the arm1 in the central part2 that for the leg1 in the superior part of the same convolution2 the center for the muscles and for general sensibility1 in the angular gyrus2 and the center for the muscles of the trunk1 in the frontal lobes4 ,in pure motor aphasia the lesion is in the posterior part of the left third frontal convolution2 in cases of pure sensory aphasia1 the lesion is in the left first temporal convolution4 ,the relation of the cerebrum to cutaneous diseases has been studied much of late1 and it is now held that the cutaneous eruptions are mainly due to the degree of inhibiting effect exerted upon the vaso-motor center4 ,the relation of the spinal cord to skin eruptions has been more thoroughly investigated and more abundant evidence supplied to demonstrate the influence degeneration of the spinal cord has in causing skin diseases1 notably zoster1 urticaria1 and eczema4 ,this rheumatism1 pneumonia1 diabetes1 and some kidney diseases and liver affections are often the result of persistent nervous disturbance is now held4 ,that a high temperature 7the highest recorded7 has resulted from injuries of the spinal cord1 and where the influence of microzymes is excluded1 is not a matter of question4 ,in one instance1 the temperature reached #abb ,f41 and remained for seven weeks between #ajh and #aah ,f4 ,the patient was a lady2 the result was recovery4 ,hence it cannot be fever which kills or produces rapid softening of the heart and other organs in fatal cases of typhoid4 ,fever1 so far as it consists in elevation of temperature1 can be a simple neurosis4 ,many other items of progress might be presented did time permit1 particularly in the treatment of nervous affections1 but this ,i leave for another occasion4 99 99 99 99 99 ,,scaring ,,the ,,baby ,,out4 ,dr4 ,grangier1 surgeon in the ,french army1 writes from ,algeria3 ,a few days after the occupation of ,brizerte1 when the military authorities had forbidden1 under the severest penalties1 the discharge of firearms within the town1 the whole garrison was awakened at three o'clock one morning by the tremendous explosion of a heavily loaded gun in the neighborhood of the ramparts2 a guard of soldiers rushed into the house from whence the sound had come1 and found a woman lying on the floor with a newly born babe between her thighs4 ,the father of the child stood over his wife with the smoking musket still in his hand1 but his intentions in firing the gun had been wholly medical1 and not hostile to the ,french troops4 ,the husband discovered that his wife had been in labor for thirty-six hours4 ,labor was slow and the contractions weak and far apart4 ,he had thought it advisable to provoke speedy contraction1 and1 following the ,algerian custom to scare the baby out1 he had fired the musket near his wife's ear2 instantanously the accouchement was terminated4 ,after being imprisoned twenty-four hours1 the ,arab was released4--,cincinnati ,lancet4 99 99 99 99 99 ,,elastic ,,limit ,,in ,,metal4 ,the ,engineering and ,mining ,journal raises the question whether steel1 which is becoming so popular a substitute for wrought iron1 will1 when it is subjected to continuous strain in suspension bridges and other similar structures1 do as well as iron has proved that it can4 ,recent tests of sections from the cables at ,fairmount ,park1 ,philadelphia1 and at ,niagara ,falls show that long use has not materially changed the structure4 ,the ,journal says3 ,it is a serious question1 and one which time only can completely answer1 whether steel structures will prove as uniformly and permanently reliable as wrought iron has proved itself to be4 ,in other words1 whether the fibrous texture of wrought iron can be equaled in this respect by the granulated texture of steel or ingot iron4 ,in this connection it is interesting to note that the fibrous texture referred to is imparted to wrought iron by the presence in it of a small proportion of slag from the puddling furnace1 and that this can be secured in the ,bessemer converter also if desired4 ,the so-called ,klein-,bessemerei1 carried on at ,avesta in ,sweden for several years past1 produces an exclusively soft1 fibrous iron by the simple device of pouring slag and iron together into the ingot mould4 ,this requires however a very small charge 7usually not more than half a ton71 and a direct pouring from the converter1 without the intervention of a ladle1 which would chill the slag4 ,the effect of the introduction of slag would seem to be to retrace the steps usually taken in producing steel1 viz41 to separate the iron from its impurities1 and then to add definite quantities of carbon and such other ingredients as are found to neutralize the effects of certain impurities not fully removed4 ,the most intelligent engineers1 after ascertaining by exhaustive physical tests what they need1 present their requirements to the iron and steel makers1 whose practical experience and science guide them in the protracted metallurgical experiments necessary to find the exact process required4 ,the engineer verifies the product by further tests1 and by practical use may find that his requirement needs further modifications4 ,as a result of all this care1 some degree of certainty is secured as to what the material may be expected to do4 ,no doubt the chemical composition of the slag used at ,avesta was known and met some equally well known want in the iron1 and thus the result arrived at was one which had been definitely and intelligently sought4 ,an important factor in selecting material for the cables of suspension bridges is its true elastic limit4 ,by this term we mean the percentage of the total strength of the material which it can exert continuously without losing its resilience1 i4e41 its power to resume its former shape and position when stress is removed4 ,now1 in the case particularly of steel wire as commonly furnished in spiral coils1 the curve put into the wire in the process of manufacture seriously diminishes this available sustaining power4 ,for it is evident that it would be unsafe to subject these cables at any time to a stress beyond their elastic limit4 ,if1 e4g41 a snowstorm or a great crowd of people should load a bridge beyond this limit1 when the extra weight was removed the cables could not bring the bridge back to its normal place1 and the result would be a permanent flattening and weakening of the arch4 ,by a process invented and patented by ,col4 ,paine1 the wire in the ,new ,york and ,brooklyn bridge was furnished straight instead of curved4 ,now1 if a short piece of common steel wire is taken from the coil1 and pulled toward a straight position1 and then released1 it springs back into its former curve2 but if a short piece of the straight-furnished wire that was put into this bridge is bent1 and then released1 it springs back toward its straight position4 ,it is easy to see that if a curved wire is pulled straight1 there must occur a distention of the particles on the inside of the curve and a compression of those on the outside4 ,the inside is in fact strained past its elastic limit before any stress comes upon the outside4 ,hence1 after the wire has been pulled straight1 the elastic limit of only a portion of it can be taken into the account in calculating the load that can safely be put upon it4 ,in the case of curved steel wire pulled straight1 its ultimate strength was found to be only about #ij per cent4 that of similar wire furnished straight by this process4 ,the superior ductility of iron wire in some measure compensates for the distention of the particles on the inside of the curve1 and that is a reason why it has heretofore been used for suspension bridges4 ,but with straight steel wire there is no such distention1 and its entire elastic limit is available4 ,this elastic limit is #ff per cent4 of the ultimate strength1 and1 besides1 that ultimate strength is #aj per cent4 greater than that of similar curved wire4 ,thus if we have a curved steel wire large enough to sustain #a1jjj lb4 without breaking1 a similar straight wire1 such as those in this bridge1 will hold up #a1ajj lb41 and #ff per cent4 of this #a1ajj lb #gbj lb4 ,the elastic limit of curved wire has never been determined1 since any stress that will cause it to reach a straight line is beyond the elastic limit of the inside of its sectional area4 ,that of curved iron wire has been estimated at #dj per cent4 of its ultimate strength1 which is about half the ultimate strength of curved steel wire2 that is1 it would be unsafe to put more than #dj per cent4 of #ejj lb4--or #bjj lb4--upon a curved iron wire when a straight steel one can sustain #gbj lb4 without injury4 ,in the ,new ,york and ,brooklyn bridge the cost of a sufficient amount of such iron wire as is used in all other suspension bridges would have been some #bjj1jjj greater than that of the straight steel wire which was used4 ,at five per cent41 this effects an annual saving in interest of #aj1jjj4 ,there must1 too1 be a considerable saving in the current expense for painting and care1 to say nothing of the more neat and elegant appearance of the less bulky steel4 ,and as the whole area of the section of these wires is subjected to an even strain that is always far within the elastic limit1 there is no danger of a change of structure under that stress4 ,it is highly probable--although ,col4 ,paine has been too busy to work up the matter--that piano wire made in this straight method could be drawn up to and kept at pitch1 without approaching very near the elastic limit4 ,in that case not only would they seldom if ever require tuning1 but probably all along the tone would be more satisfactory4 ,and there would not be those exasperating periods when the pitch is not quite perfect1 but yet is not far enough out to make it seem worth while to send for a tuner4 99 99 99 99 99 ,a catalogue1 containing brief notices of many important scientific papers heretofore published in the ,,supplement1 may be had gratis at this office4 99 99 99 99 99 ,,the ,,scientific ,,american ,,supplement4 ,,published ,,weekly4 ,terms of ,subscription1 #e a ,year4 ,sent by mail1 postage prepaid1 to subscribers in any part of the ,united ,states or ,canada4 ,six dollars a year1 sent1 prepaid1 to any foreign country4 ,all the back numbers of ,,the ,,supplement1 from the commencement1 ,january #a1 #ahgf1 can be had4 ,price1 #aj cents each4 ,all the back volumes of ,,the 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