656 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



with the iron and the hydrogen of the water will be set free. If steam is 

 passed through heated carbon, in the shape of burning coals, there is no 

 doubt that it aids combustion, and the theory of it is this: the hot bed of 

 coals does not get air or oxygen enough to burn well, now the oxygen of 

 the steam unites with the carbon, and produces a little better combustion. 

 The whole question resolves itself thus, if it requires the same amount of 

 heat to decompose water as can ever be got from it when decomposed, it is 

 certainly cheaper to use heat first without resorting to the decomposing 

 process. 



Mr, Bartlett endeavored to make the subject clearly perceptible to every 

 one present by the use of small blocks of wood as symbols of the chemical 

 elements of the various substances used as fuel. He explained the combi- 

 nations of these elements before and after combustion, and concluded by 

 Baying that it is clearly demonstrated by repeated experiments that it takes 

 just as much heat to decompose water as it is possible to get from it by 

 burning the two elements of which it is composed. Therefore the use of 

 water or steam in a furnace produces a loss of heat. 



Mr. Bnssett, of Salem, Mass., stated that at Providence, R. T., are twelve 

 retorts heated by using super-heated steam in connection with ordinary 

 fuel by which a great saving was effected. The fire-box was filled to the 

 top with coal, and the steam was passed through the sides of the fire-box 

 lined with fine clay into the coal. 



Mr. J. Wyatt Reid inquired whether the forcing heated air would not be 

 as effective as steam; he described a furnace in which air heated by pass- 

 ing through hollow grate bars was carried to the centre of the fire. 



Mr. Dibben said there was no doubt that there is an economy in the use 

 of steam in a furnace in one way, and that is hj preventing iron from burn- 

 ing up. For instance, in burning anthracite coal on iron grate bars, if steam 

 is sent up through the bars, into the fire, some of the intense heat is taken 

 away, and the destruction of the iron is prevented. This is done on loco- 

 motives by the Hudson River Railroad .Company. The steam also had the 

 effect of clearing the passage through the fire, and there was a more intense 

 heat produced in particular parts of the furnace. 



Mr, J. A Miller stated that there were some new furnaces erected in this 

 city, by which as great a saving is effected by using air, as is claimed to 

 be made by using steam; these he would explain in full at the next meet- 

 ing. 



Mr. Fisher took very strong ground against the assertion that there was 

 any gain of heat by the use of water, it was a very old device. Clark, of 

 England, had used it for the purpose of forcing in air to the furnace of a 

 locomotive, but it was not now much used. 



Mr. Rosevelt and several other gentlemen spoke. 



The discussion was protracted to a late hour, when the Chairman invited 

 Prof. Charles A. Joy, of Columbia College, who had been present through- 

 out, to express his views with regard to the effect of using steam in small 

 quantities in furnaces during the ordinary process of combustion. 



Prof. Joy remarked that he had made no experiments for the purpose of 

 thi'owing light on the point alluded to by the Chairman. He was aware, 



