Steam:
Its Generation and Use

only 3.15 per cent, of entrained water, leaving 5863 pounds of dry steam per hour, enough at the rate of 30 pounds of dry steam per hour for each horse-power to supply 195 horse-power, which is 30 per cent, above their rated power. The general result is a difference of about 7 per different engineers, have been condensed for the purpose of a more ready comparison. v Test made at Harrison & Havemeyer’s Sugar Refinery, Philadelphia, January, 1879, by their engineer and usual fireman, under general work- ing conditions, for five days of 24 hours each : The Brooklyn Sugar Refining Co., Brooklyn, N. Y„ 5 orders, 1876 to 1888, 3952 H. P. Babcock & Wilcox Boilers. cent, in favor of the Babcock & Wilcox boilers, arrived at by four independent methods of com- parison, all free from objection, and, together, mutually confirmatory in the highest degree. This comparison leaves out of view all disparity of coal save the ascertained difference in surface water; this, if allowed for, would greatly increase the difference. Other Tests The following tests, showing the evaporative efficiency of the Babcock & XVilcox boilers, actual and comparative, with different kinds of fuel, which have been made at various times, by Coal, anthracite, egg size, not screened. Duration of test, hours, ...••• 12°- Average steam pressure, in pounds, . . • 62.50 Average temperature of feed,....................165.8c Water evaporated,..............................733,660 Coal fired, .................................. 79»’47 Per cent, of ash,......................... x3-7 Combustible,...............................lbs. 68,297.5 Grate surface,...........................sq.ft. 5°-75 Coal consumed per sq. foot of grate per hour, 12.99 Water evaporated, in pounds ; Per lb. coal under actual conditions, . . 9.27 “ combustible, “ “ i°-74 “ coal from and at 212°, . . . 9-7* “ combustible “ . . . 11.6 Rated horse-power, ............................... ’9° Horse-power developed,.............................220 Per cent, above rated capacity.................. 13-63 88