710 Report of the Consulting Engineers on the Trials of 
the free hydrogen with the oxygen of the atmosphere, will be in 
the form of steam, and will absorb 
•0756 lbs. X {(212' -70°) • 238 + (385°- 212)° x -37} 10-92 lbs. 
= 80 units, 
while the rest would assume the form of permanent gases at 
385° temperature, and would therefore contain above the tem- 
perature of 70° 
6 -5441 lbs. X 315° X '169 (the true specific heat of air) 
X 10-92 = 3804 units, 
making in all 3884 units. 
No. 3. — In evaporating the water in the coal, and heating the 
steam so produced to the temperature of the smoke-box. 
The coal used contained 0'0083 parts of water as moisture, 
and 0-0287 parts of hydrogen and oxygen in the form of 
inchoate water, together -037 parts of water, which, as in the 
case of the wood, would have to be heated to 212°, would have 
to be evaporated at that temperature, and the resulting steam 
of which would have to be raised to 385°. This for the 193 lbs. 
of coal consumed would absorb 193 lbs. X "037 X 1172-6 u. 
= 8374 units, the -037 water amounting to 7-141 lb. in the 
193 lbs. 
No. 4. — In heating the coal and the air necessary for its com- 
bustion from 70^ to 385°. 
The analysis shows that '0333 parts of hydrogen were avail- 
able for combustion and formed therefore '2997 parts of water. 
The heat expended in heating this from 70° to the temperature 
of the smoke box would be 
= - 2997 X {(212° -70°) '238 + (385°-212°) x -37)193 lbs. 
= 5611 units. 
Deducting the moisture, the inchoate water, and the free 
hydrogen, together -0703, there remain "9297 parts, with 
which, to obtain perfect combustion, should be associated the 
11-38 lbs. of air, less the oxygen already used foi: the com- 
bustion of the free hydrogen, making 12-04 lbs. per 1 lb. of 
coal, which have to be heated 315°, requiring 
12-04 lbs. X 315° X -169 X 193 lbs. = 123,710 units, 
making in all 129,321 units. 
No. 5. — Displacement of the atmosphere by the products of 
combustion of the wood and coal. 
As above stated, analysis shows that 11 '38 lbs. of air were 
needed for the complete combustion of 1 lb. of coal and 6-08 lbs, 
for 1 lb. of dry wood. One pound of air at 32° or 492° absolute 
