. The locomotive engineer . ve lado with it. But let us take a case that more nearly representsaverage practice. Say we are making steam in aboiler nl 80 pounds gauge pressure, and that thewater supplied to the boiler is heated by exhauststeam to 212°. By referring to steam tables, wefind that a pound of steam of 80 pounds pressurecontains 1,213 heat unlL-?. and subtracting the 212heat unita in the water lejives heat units to beimpartetl. Dividing the 9,800 heat units which weAnd available in the pound of coal by this givea pounds of water that tliis pound of coal willevaporate u
. The locomotive engineer . ve lado with it. But let us take a case that more nearly representsaverage practice. Say we are making steam in aboiler nl 80 pounds gauge pressure, and that thewater supplied to the boiler is heated by exhauststeam to 212°. By referring to steam tables, wefind that a pound of steam of 80 pounds pressurecontains 1,213 heat unlL-?. and subtracting the 212heat unita in the water lejives heat units to beimpartetl. Dividing the 9,800 heat units which weAnd available in the pound of coal by this givea pounds of water that tliis pound of coal willevaporate under gauge pressure of 80 pounds, thefeed water being healed to 212. Bui to do thisthe conditious must all be execlkni, and ihe coal ofa good quality. In practice, if you do not find tliatyou are evaporating from 8i to 9 pounds of water,at ordinary pressure, for each pouud of coul burned,you ought to look about for the reasons. Theymay or may not be such its you can control, butwhether they are or are not you ought to know. A LiOBT LocoMorrvK. oxide, there is danger that a gooil deal of it may bemade, and pass away unconsumed, 1 aay uucon-Bumed, for if this carbonic oxide is, while hot, sup-plied with sufllcient oxygen, it may be burnedwithout loss. Hence the utility, where deep firesarc burned, of admitting air above the fire. Now (he engineer is, so to speak, between twofires. If loo much air is admitted llien there is aloss; if too little there may be a greater loss. Thisis something in reganl to which an engineer mustill the mam be his own guide. All of you whohave hud considerable experience in burning coalknow with more or leas certainty by the looks ofyour lire whether or nol il is burning know you must not have air holes in it. andthat it should have that peculiar live and even ap-pearance that no description can cover. With anykind of coal, if there are dull places in the fire, itmeans waste In regard to the great waste inci-ilent upon burning coal to car
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectrailroa, bookyear1888
