92 Transactions of the American Institute. 



EXHIBIT H. 



Calculation of the Log of the Phleger Boiler, exhibited at 

 the Fair of the American Institute, November, 1871. 



Determination of the heat carried away by the condensing water dis- 

 charged from the tank during the twelve hours trial. 



Units. 



To 10 a. m., 101 cub. ft. @ 62£ lbs. =6,312.50 lbs. @ 



range of 106°.35 Fahr.= 671, 334. 3S 



To 9.00 p. m., 4909 cub. ft. @ 62^ lbs. =306,812.50 



lbs. @ range of-72°.49 Fahr.= 22,240,838.13 



To 9.45 p. m., 373 cub. ft. @ 62i lbs.=23,312.5 lbs. 



@ range of 22°.98 Fahr.= 535,721.25 



(a) Total British thermal units 23 , 447 , 893 . 76 



Determination of heat carried off by evaporation at the surface of 



the tank. 



Units. 



367.19 lbs. x 1030°.45 (latent heat at 120°.122 Fahr.=(5 ) 378,370.94 

 Determination of heat carried away by water of condensation. 



Units. 



20,428 lbs. @ 8°.73 (range=4°.3S-45°.65)=(c) . . 178,336.44 



Total heat derived from fuel, as determined above. 



Thermal units. 



23,447,893.76 + 378,370.94 + 178,336.44= 24,004,601.14 



Deduct four per cent of (a) for errors (leakage and 



meters). . . , 960,184.05 



Final and corrected result 23,066,685,39 



British thermal units per lb. combustible, 23,066,685.39-=-2274= 

 10,143.66. 



Equivalent evaporation of 'water, temperature 212° Fahr., atmos- 

 pheric pressure=10,143.66-=-966.6=10.49 lbs. 



Total weight of water actually evaporated, by equation Hx+h 

 ( W— x ) = u, where 



jS==heat transferred by each lb. of steam. 

 h =heat carried into tank by one lb. of water. 

 x = weight steam, in lbs. 

 17= total weight feed. 

 Z7= total quantity of heat. 

 1157.31®+ 266.16 ( W-x )=23,066,685.39. 

 =19782.94 lbs. steam. 

 W—x- 645.06 lbs. water. 



Apparent results. Real results. 



Water evaporated per lb. of coal.? . ^2^=7.26 1 9 g|go 94 =T.07 

 "Water evaporated per lb. of com- 

 bustible ^t^. = 8.95 1 9 ilV 4 = 8.70" 



