Show i r tf ELECTRICITYS NEW RIVAL 3 AS EUCCTTMCITY KAS GOXQUERED STELVJI SO CCKJLPRESSED Alit IS yOV DOING UATTJLE ItOVAfe WITH THE UXKXOWS FORCE IMPROVED IM-PROVED aHAXHIATERY stD 3IEOIHODS OF APPLICATION HAVE CHEAPEXE 11 so TH2MI IT WILL SOON BE PIPED Ef MUSS LIKE WATCH AAT GAS THE ADVAXOD DUB LARGELY TO AJIERIQS GENIuS Copyright 1E96 by the S S McClure Coo It Is only with its recent very successful application to the purposes of street trac tioa that the general public has awakened awak-ened to the iirnierse utility and the wide possibilities of compressed air Within a few years very largely within the last decade I cade it has come to undertake such a multiplicity of tasks that a mere enumera IVto of them is astonishing We have Jens known of the value of air for sop i 1 I ping cars in the shape of the Westinghouse I Westing-house brake now It is used to start cars I i as well We are fairly familiar with Its work in drilling out rock excavations for I oJ the modern ky scraper it is another matter I 1 mat-ter to learn that this same compressed air drill used In the mine has enormously added to our wealth or gold and silver of coal and Iron and copper tiiroujrn ihv cheapening1 of the production It has caused caus-ed It is still a further matter of surprise i that this protean force has turned canal digger and was the largest single agent I in the construction of Chicago great dralragc canal in many respects the nost wonderful canaJ In tlieorid We are acaualrted with the PNEUMATIC DYNAMITE GUN 1Y where compressed air Is employed to j throw a huge charge of high explosive to the distance of a mile or so It is I another an-other matter to think of this same force cleats nj carpets and dusting cushions It has been successfully employed to pre locomotives in mines It is equally useful J use-ful to shear sheep It will operate a block signal or it will steer a ship It was a j no1 thing when We read of tho buildings 01 the Worlds far being patiue by coin pressed air but it Is a common enough I 1tb thing now it is even used to polish and j sandpaper cars as well In Paris It is i t employed to iun clocks and as a cooling agent In refrlseratois It runs motors 1 propels sewing machines lifts scfenery in tin trains cues lathes and printing PI < < aid st rj t ers and Is the motive I power In all the little shops which turn j out tne curious articles de Paris which i at to fcirn tt buuico of revenue to the j IrJ < ii n L ajJial V e know ot Its use in carrying mails In pneumatic tubes It1s now i > rjj w M 10 make it carry freight It is employed to raise sunken easels and very shortly it will be introduced on the Erie canal to Prorate the locks By the Dutton pneu I i atlo highlift lock it is proposed to xck I up a great ocean liner and lift it as high I as Niagara with lets effort and In less time than it now requires to elevate a I I clumsy barge the height of a bean pole In the railroad shops it Is everywhere ruimlnp machinery hoisting huge loads riveting bolts driving hammers Is employed em-ployed in forging and in every conceivable conceiv-able variety of work In Kansas City beeves are slaughtered and the meat dressed all by compressd air It is an r excellent ump especially for deep wells It Is used to pip oil and pump chemicals It is used by the physician and tha surgeon sur-geon in many delicate operations It makes a good elevator hoist for grain With compressed air you may dump a whole train of coal or dirt cars with tho y pressuie of your thumb It is wed in sculpture and In stone carving It makes a good dredge It raises and lowers railroad rail-road gates it will copy jour letters run summer fnns it is used In the sugar refinery re-finery and In the making of asphalt and I of rubber and still again in the delicate manufacture of tine silk In fact there seems hardly a limit to the uses to which it may be putt put-t THE WONDER OF IT now seems that all this has not been done long age Compressed air Is not new in the sense that electricity 43 Jiev Jiw l then does it ome that it is only of very recent years that It has been generally used Piobbiy the chief reason will appear ap-pear with hardly any explanation at all It was largely a mania fOr things electrical electri-cal It seems absurd to say that the business world has been carried away with a mere enthusiasm and yet this is literally tho case The beginnings of the use of compressed air were almost coincident coin-cident with the introducticn of electricity And compressed air being known its posibnuiea being capable ol more or less accurate definition it was literally neg looted for HT less known more showy and m sifnoun rival It is a frequent matter of remark now that had a tithe ot the money and brains 1 and genius been expended in the development develop-ment of compressed air as has been given to electricity the present relation of the two forces would be reversed For a long time electricity represented the unknown f Its possibilities were unquestionably great for a time they appeared boundless bound-less Nw however its capacities are more clearly outlined its powers definite ly known and mechanical and inventhe genius is turning to the development of the force of air The three chief factors of recent pro gnsss are perhaps the perfection or the compressing apparatus and of tho rehe tin t-in Process and of the nonbursting steel reservoir When compressed air was first I tried it was found that the loss of power in the process was enormous Then again there wer thermodynamic difficulties vlthout number If you put a thousand cubic feet of air into the space of a single i sin-gle one you develop a high degree of heat and In order to use the air this heat < y must in some way be drawn off Similarly Simi-larly air at high pressure when released oools tepidly the result is freezing and clogging It used to be thought that these difficulties ere for practical purposes insuperable I in-superable Now however these very difficulties or rather thf CAUSES WHICH PRODUCE THEe THE-e turning to profitto such excellent profit ab to afford an apparent paradox It sterns idle to assert that you are able to get out of a machine as much power as YOU put into itthat this is perpetual motion And yet this Is almost literally true in the present day use of compressed I airIn I In this country there are air compressors compress-ors butt to perrectly that the loss of mechanical me-chanical efficiency in compression Is only a iut 5 per cent and or the total efli ciency only 15 or 20 per cent that is to say if you use up a hundred horse power In the compression of the air you will have a force that will in the case of the best type of compressors give you eighty or ninety hore power in return Here incidentally is another triumph of American I Amer-ican mechanical l genius In the famous Popp system in Farm where compressed air is distributed through 125 miles of mains the ellicloncy realized is less than I 50 pfjr cent c little more than half that in this country The compressor which does this work I Is a bcauufUi machine of what is known as the four stage type That is to say the air is first < Irien up to about eighty pounds Dresture and then cooled by a water jacket then turned into a second cylinder where It is compressed still further fur-ther then cooled again and so on up to the desired point the air thus being kept I at about tha ame temperauri as that of what Mr Shakespeare would call the circumambient atmosphere Now if the air br used lathis condition technically kncwn as cold it will as I have already noted realize ail efficiency of 80 per cent or more Blt if as It is released It is passed through a heater or shot through t SUPERHEATED HOT WATER It will under the 1 well known properties H ofiulr cnormousiy expand It has been Jow > d possible to add one horce power to 5ach horse poorer of compressed air for oneeighth the original cost of compression compres-sion One form of heater that has been devised adds iS per cent of efficiency with about this expenditure in the shape N of coal burned Adding to > the efficiency of the com nressec air when used cold to the amount of power developed by reheating It will be sewi that the total amount of power realizfid is about equal to the power I pow-er expended generation I Theoretically the total efficiency is actually I ac-tually greater but it is a matter of fact In practical ise It is slightly less It is nevertheless true that In tests made on the Hard5e street car motor It has been found possible to realize about 5 pr cent more energy or work from a given quantity quan-tity of coal IT burning the coal In a good type of air compressing apparatus and using this air under reheating in the Hardie motor than if the coal were put into an ordinary locomotive and used directly for the generajtor of steam power c i r The apparent paradox is due to the added add-ed power gained from reheating the air Competing American and Parisian appliances ap-pliances again the efficiency developed under the Popp system In Paris with reheating re-heating is stated at from 60 to 70 percent per-cent 73 per cent being given as the maximum max-imum Assuming a loss of from 3 to 5 ner cent under the American method it follows that the degree of efficiency realized re-alized under the Popp system is something some-thing more than 20 per cent less than that attained in this country It is to be noted further that compressed air began to be used in Paris long before it was taken up In this country the 7Iekarskl system of surface transit alone having been In operation for more than ten years With the perfection of compressing apparatus ap-paratus and the reheating system has come a third important development which has chiefly made possible the use ofCOMPRESSED COMPRESSED AIR FOR STREETCARS STREET-CARS This is the invention of what is known as the Mannesman tube for the storage of the air The latter is simply a seamless seam-less l tube or flask made of mild steel of any desired size and capable of receiving and holding air charged to a very high pressure Up to the time of its introduction introduc-tion it had been practically impossible to nrovide a suitable reservoir or holder Those which were employed were enormously enor-mously heavy took up a wholly impracticable imprac-ticable amount of space very often exploded ex-ploded and always leaked The loss in one way or another was very great The Mannesman tube solved the problem by providing a chest that was practically iiir tight that if it burst did not fly to pieces but simply ripped as would a leather bag and was therefore not a hazard to life it was light and it took up very little space These tubes are now made to carry almost al-most any charge of air In the case of the Hardie motor their testing strength is 4000 pounds per square inch and their maximum charge about 2000 pounds These steel cylinders are distributed underneath un-derneath the seats and under the car bery in such a way as not to infringe upon the room of an ordinary street car and hold fiftyone cubic feet of air sufficient suffi-cient to run the car fifteen or eighteen miles For the reader apprehensive of siting over so highly charged a device it may be stated that the whole effect of an explosion of one of these tubes would bo a loud report a rush of air and a slight disturbance of the atmosphere immediately adjacent There would be no flying pieces of pipe no steam or hot air to scald and all you would < see afterward after-ward would be an ugly rent in the tube Such is THE ROUGH OUTLINE of the important elements of the advance in the art The improvement in the devices de-vices for compression represented economy econ-omy of production the development of the reheating process represented a large gain in the amount of power derived from I the air and In consequence a still further fur-ther cheapening while the seamless tube offered at once safety storage and insurance I insur-ance front loss Bv virtue of these improvements the tOhfe i i reduction in the cost of manufacture has i been very great A3 computed by Compressed i Com-pressed Air to the editor of which I am indebted for much information air may I now be compressed to high pressure for considerably less than 3 cents per 1000 I I I cubic feet i It Is urobable that air could be com j pressed piped through a large city and i sold at a profit for 5 cents It Is to this cheapening not less than I to its mobility and the ease with which it may be applied that the wide use of I compressed air at the present time is due Once a cheap power was offered it thereafter there-after remain wi but to develop the various j special devices and appliances by wl chIt ch-it could be utilized One after another these inventions have been made until it Is now 1 estimated avfhe this wonderful I force is employed for something more I than 200 distinct purposes When we consider the probable future I of the new force as such it may fairly be called we live over again our experience with its rival electricity The immediate I conclusion after a survey of the sufficiently sufficient-ly marvelous things that It can and actually actu-ally does do is that there is hardly a limit to be set to its possibilities But a brief calculation will define its limits with some I accuracy To compress a given quantity of air requires a given amount of power and the result to be realized in work cannot i can-not be greater than the amount of power i I employed in generation Otherwise you have perpetual motion a proposition that It not patentable It follows with a reasonable rea-sonable degree of cogency that compressed air U not be utilized save where by reason of greater utility or convenience it is I economy to convert your original power into this FORM OF POTENTIAL ENERGY I is not probable that compressed air will be used to run railway trains or steamships ships although i is conceivable that It might be valuable in days to com when we shall fly through the heavens But on the other hand compressed air is superior to steam piping or any form o shafting for the conveyance of power A long series of tests at the Pullman shops near Chicago h demonstrated the immense economy which lies In its use and It will therefore be universally introduced at these works a it is in many other great car shops as In Jersey City Topeka Omaha and elsewhere far the however By largest use will come when compressed air is manufactured manufactur-ed in huge central stations similar to that of the Popp system In Paris and Is distributed dis-tributed in mains and sold commercially just as are gas and water and electricity Then hardly a limit may be set to its usefulness use-fulness I will be in every home a in every office Every house will have Its elevator by which with the turn of your hand you may lift yourself from floor to floor The housewife will sweep and dust with air and I do not doubt that in time madam it will come to wash your dlsh sand s-and smash your choicest chInaware with all the dexterity if not with the same sangfroid of your most accomplished handmaiden It may supply fresh and cooling air in the summer time to the overheated over-heated office the factory or the sleeping room The time may come when it will whisk a letter from New York to Son Francisco between the opening and the closing of the business day What else it may do Is probably wrapped in the brain of the seed and neglected gentleman gentle-man of invention and applied science CARL SNYDER |