846 Transactions of the American Institute. 



the various methods of employing anthracite and bituminous coals 

 as fuel, at the worlis of Messrs. Whelpley and Storer, East Boston, 

 Mass. A furnace for burning pulverized coal was there erected, 

 which the owners hav^e used for several years in their ingenious 

 process for the reduction of metallic ores. No official report of the 

 combustion trials made with this furnace has yet appeared, but 

 the results may be briefly stated. A series of experiments, each 

 lasting forty-eight hours, showed the relative heating power of ' 

 bituminous coal in lumps of fom- inches cube, burned on a grate 

 with a forced blast under an ordinary tubular boiler, and the same 

 kind of coal, oue-third in lumps burned on a grate, and two-thirds 

 slack pulverized, and driven in above the fire with a forced blast. 

 Under conditions as nearly as like as practicable it was found that an 

 average of one pound of lump coal evaporated eight and a half 

 pounds of water from a temperature of one hundred and forty 

 degrees Fahrenheit, while one-third of a pound of lump coal and 

 two-thirds of a pound of pulverized coal evaporated nine and a half 

 pounds of water from the same temperature. The combustion was so 

 perfect that in neither case was the residual ashes more than eight 

 per cent of the coal used. lu the latter part of the experiment 

 the increased useful effect of pulverized coal over lump coal rose 

 from twelve to thirty per cent, owing to the acquired skill of the 

 fireman in increasing and regulating the heat. Assuming that the 

 heat generated by pulverized coal is barely equal to that of lump 

 coal, these experiments solved most satisfactorily the q uestion what 

 is to be done with the vast quantity of fine fuel Avhich now lies at 

 the mouths of coal mines in this country and in Europe. Sta- 

 tistics show that while the mines of Great Britain yield more than 

 100,000,000 tons of marketable coal per annum, about 30,000,000 

 tons more of waste coal are left at the mines, The percentage of 

 waste coal at the anthracite mines of this country is somewhat less 

 than at the bituminous coal mines, yet it has been estimated at 

 about twenty-five per cent of the whole weight Ijrought to the 

 surface. The utilization of this waste coal would virtually add 

 one-third more to the value of the annual product of American 

 mines, and eventually cause a corresponding diminution of the 

 prices paid by the consumer; therefore it ma}' be safely averred 

 that'no improvement has been latel}^ proposed which compares in 

 general importance with that which would make available the 

 waste product of coal mines. The inventors of this process of 

 utilizing fine coal are about applying their apparatus to locomotives. 



