592 ANNUAL KECOKD OF SCIENCE AND INDUSTRY. 



explanation. It is, therefore, a matter of peculiar interest 

 to record the fact that during the past year certain substan- 

 tial improvements in the mode of producing gaseous fuel 

 were made by Mr. M. II. Strong, of Brooklyn, the opera- 

 tion of which appears to have demonstrated its entire prac- 

 ticability. Retaining the general principle of the " water- 

 gas" process of Lowe, this inventor conceived the idea of 

 employing coal in pulverulent form aiming to utilize coal- 

 dust (culm), because of its abundance and cheapness with 

 the idea that in this form it would be peculiarly fitted for 

 rapid and economical decomposition by contact with highly 

 heated steam. Acting upon this principle, Mr. Strong has 

 contrived a modification of the generating and superheating 

 apparatus of Lowe, in which highly heated steam, instead of 

 being led through a mass of incandescent coal, as is the prac- 

 tice with the Lowe system, is allowed to act directly upon 

 the finely divided carbon. As our purpose here is to record 

 results, we must refer our readers for the details of the ap- 

 paratus to the elaborate descriptions that have appeared in 

 the technical papers during the past year. Experiments 

 made at Mount Vernon, N. Y., continued during several 

 months, to test the capabilities of the Strong system, demon- 

 strated that 50,000 cubic feet of water-gas could be obtained 

 from 2240 lbs. of anthracite coal, or, stated differently, at a 

 cost of from 6 to 8 cents per 1000 feet. They further demon- 

 strated that this weight of fuel, including the quantity used 

 under the boiler, afforded the basis of a safe estimate for a 

 reasonably large scale of operations, since, in practice, better 

 results have been obtained. The labor necessary to pro- 

 duce half a million cubic feet of this gas in twenty-four hours 

 is affirmed to be three men on the shift. Dr. Gideon E. 

 Moore gives the following as the composition by volume of 

 the gas obtained by the mode above described : 



Oxygen 0.77 per cent. 



( larbonic acid 2.0. r > " 



Nitrogen 4.43 " 



Carbonic oxide. . . .>r>.8S per cent. 



Hydrogen 52.76 " 



Marsh-gas 4.11 



Total 100.00 per cent. 



The same chemist has published an admirable investiga- 

 tion of the calorific elements of the Strong gas, and of its 

 heating power in comparison with other fuels. He reaches 

 the apparently paradoxical result that the practical heating 



