314 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



"Wood Spirit 5,307 



Dry Wood 4,025 



Moist Wood 3,100 



Carbonic Oxide 2,400 



The gases and oils mentioned are too expensive to be used. It will be 

 noticed that at the same price per ton, anthracite would be a cheaper fuel 

 than charcoal, bituminous coal, or coke. It is very compact, brilliant, and 

 comparatively clean. Fortunatel}'' for us, it is the most abundant fuel in 

 our market. These experiments were made before the discovery of Ameri- 

 can petroleum. Judging' from analogy, its place in the table would proba- 

 bly be next to the oil of turpentine. 



Mr. L. B. Page presented the report of Chief-Engineers Wood, Whipple 

 and Stimers to the Secretary of the Navy, of experiments they had made 

 in burning crude petroleum, in an apparatus invented for the purpose, con- 

 sisting of a series of corrugated recesses upon a vertical cone of cast-iroa 

 placed in the furnace of the boiler, the base of which formed a semicircular 

 disc or annular reservoir, and the depth of v/hich in section was about half 

 its diameter, and served to contain such heavier and less inflammable por- 

 tions of the oils as were not consumed or vaporized in passing over these 

 smaller corrugated recesses. The results gave for crude petr6leum an 

 evaporation of 10.36 pounds of watei for one pound of oil, and for anthra- 

 cite 5.1 pounds of water per pound of coal. 



Mr. W. Sewell said a ton of anthracite coal ought to evaporate from 8 to 

 9 tons of water. Some reports have been made giving the amount of water 

 evaporated by one pound of coal as high as 11.062 lbs. Several members 

 coincided with the opinion expressed b}^ Mr. Sewell. 



Mr. Dibben inquired why, in the table presented, coal containing both 

 carbon and hydrogen was shown to have less heating effect than carbon 

 alone, when the effect of hydrogen alone is given at more than three times 

 that of anthracite ? 



Mr. Geo. Bartlett explained this apparent anomaly. Hydrogen, as a gas, 

 has great heating power when uniting with eight times its weight of 

 oxygen, and forming water; but hydrogen in a solid form, which it takes in 

 combination with carbon, has scarcely any heating power. This is fully 

 accounted for by D. K. Clarke, of England, in his work on railway machin- 

 ery. His deductions from experiments were that the bituminous coal which 

 contained the least gas — that is, contained the most carbon and the least 

 flame, was the most effective. In the locomotive boiler, he found that soft 

 coal is capable of about two-thirds, or sixtj^-six per cent., of the duty of an 

 equal weight of coke. This conclusion is not aflccted by the very superior 

 heating power of hydrogen gas, when burnt with ox^'gen, amounting to 

 several times that of carbon, and the apparent value of an excess of hydro- 

 gen in coal. The hydrogen in coal being in a solid form, it must^be brought 

 to the state of gas before combustion. This conversion absorbs more heat 

 than in the case of carbon, because two volumes of iiydrogen gas are re- 

 quired to unite with one volume of oxj'gen. 



The Chairman alluded to the erroneous view of those who hoped to in- 

 crease the quantity of heat by dividing the process of combustion into two 

 stages: that is, b}'^ first uniting carbon with one atom of oxygen, forming 

 carbonic oxide gas, and then by combining the carbonic oxide with another 



