BOILER NQ. 19. 123 



Co.il consumed, dry, ...... . .13,293 Ibs. 



Percentage of ash, ........ 8.7 parcsnt. 



Water evaporated, ....... 113,115 Ibs. 



Coal per hour, ......... 1,307.0 Ibs. 



Coal per hour per square foot of grate, . . . . 10.9 Ibs. 



Water per hour, ........ 11,125.6 Ibs. 



Water per hour per square foot of heating surface, . 3.1 Ibs. 



Horse-power developed, ..... . . . 380 H. P. 



Boiler pressure, ........ 91 Ibs. 



Temperature of feed-water, . . . . . .117 deg. 



Temperature of escaping gases, ..... 530 deg. 



Draught suction, ........ 0.31 in. 



Watsr per pound of coal, . . . . . . 8.50 Ibs. 



Water per pound of coal from and at 212 degrees, . 9.67 Ibs. 



Water per pound of combustible from and at 212 degrees, 10.60 Ibs. 

 NOTE. The coal when fired contained 3 per cent, of moisture. 



The test on Boiler No. 19 shows the performance of Cum- 

 berland coal in boilers which were not proportioned and 

 operated in a manner to give the best results. The power devel- 

 oped is nearly 40 per cent, above the nominal capacity. The 

 rate of combustion, though only 10.9 pounds per square foot of 

 grate per hour, is high for a boiler having the relatively small 

 amount of heating surface here shown. The temperature of 

 the gases is excessive, being 530 degrees. The percentage of 

 ash is high for Cumberland coal, and indicates some inferiority 

 in the quality of the fuel. The evaporative result, as might 

 be expected from these unfavorable conditions, exhibits a low 

 degree of economy. 



Boilers No. 2O and No. 21. 



Kind of boilers, ..... Horizontal return tubular. 

 Number used, each, .... One. 

 Horse-power each (basis 12 square feet ), Eighty. 





 Age, ....... No. 20, two yrs., No. 21, one yr. 



Boilers No. 20 and 21 embrace two horizontal tubular 

 boilers set in one battery of brick work. They are provided 

 with independent flues leading to the chimney, the arrangement 

 of which is shown in the front elevation given in the following 

 cut. The general arrangement of the brick setting of each 



