PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION, 575 



the smoke by not putting the fresh coal on the top. They put it 

 in at the bottom and then raise it up. They have reconstructed 

 the grates of private houses there so as to enable them to put 

 the coal in at the bottom. 



Mr. Seely. — It is stated by good authority that only about five 

 per cent of the heat of the coal is realized. If we only add five 

 per cent additional to the five per cent already attained it will 

 be a great gain. Carbonic acid is the final product of coal. 

 You may so burn your coal that carbonic oxyde will be the final 

 product. The practical difficulty is in getting the air properly 

 mixed. Probably in heating buildings by steam we gain all the 

 advantages that can be attained in heating. There is much loss 

 in furnaces, especially in burning wood. In using a stove with a 

 short pipe about three-fourths of the heat is lost. In all stoves 

 and furnaces for heating buildings, provision should be made for 

 furnishing coal at the bottom. 



Mr. Babcock did not think the loss was to be imputed to the 

 combustion of coal. 



Dr. Stevens. — The ashes of coal is composed of alumina, pot- 

 ash, iron, &c. Red ash contains more sulphur than white ash. 

 If coal can be consumed at a low degree of heat no clinker will 

 be formed at all. I use in my family a straight cylinder stove, 

 and a sufficient amount of atmospheric air is admitted to burn the 

 gases. I light a fire in my furnace in the fall and expect it will 

 keep burning until it is put out in the spring. 



Mr. Hedrick stated that the heat used in the charring of wood 

 is at the expense of the charcoal. 



Mr. Vedder inquired whether the introduction of steam had 

 been tried in small quantities, so that the decomposition of the 

 water would increase the fire and create hydrogen, and prove an 

 advantage ? 



Mr. Hedrick said it could not be done with advantage. He 

 thought as much would be lost as would be gained. 



Dr. Vander Weyde did not think there would be anything 

 gained by the introduction of water into the fire. 



Mr. Yeeder asked Mr. Seely whether heat is the union of hy- 

 drogen with the material of flame, or whether it is a union of 

 hydrogen, carbon and oxygen, or a union of hydrogen and car- 

 bon ? 



Mr. Seely said that if two elements were united and separated 

 it would be at the expense of the heat. 



