J68 BOILER TESTS. 



The individual results of the tests made with the standard 

 grades of coal, viz : Tests No. 86 and No. 87, are not so high 

 as the best obtained from other boilers of similar type. 

 Boiler No. 41 with Cumberland coal gave an evaporation per 

 pound of combustible from and at 212 degrees of 11.81 

 pounds, and Boiler No. 42 with similar coal, gave 12.42 

 pounds. The last named boiler with anthracite coal gave 11.11 

 pounds. All of these figures- are higher than the correspond- 

 ing results obtained on Boiler No. 43. From the results of 

 a subsequent test on Boiler No. 43, which was made when it 

 was working to a greater capacity, it appears that the economy 

 of the boiler was effected by the low rate of combustion under 

 which it was worked. On the test referred to, which w^as 

 made with a mixture of pea and dust coal and Nova Scotia 

 culm, having the same proportions as those used on Test No. 

 85, the rate of combustion was increased to 15.5 pounds of 

 coal per square foot of grate per hour. The evaporation from 

 and at 212 degrees per pound of coal was 9.18 pounds, and 

 per pound of combustible 10.77 pounds, and these quantities 

 are about 7 per cent, higher than those obtained on the earlier 

 tests. The temperature of the escaping gases on the last test 

 was 375 degrees* 



Boiler No. 44. 



Kind of boiler, "Double deck," hor. ret. tub. 



Number used, Four. 



Horse-power (collective, basis 15 square feet ), Three hundred and twenty. 

 Kind of coal, . | Eureka^Cumberland, Bitu- 



Age, . . . . . . . . New. 



Boiler No. 44 consists of a plant of four double-deck boilers 

 set in one battery of brick work in the general manner shown in 

 the cuts of Boilers No. 41 and No. 42. Like those referred to, 

 this boiler has two shells, one above the other. The lower one 

 is completely filled with tubes, and by this means the area of 

 heating surface and the area through the tubes is much larger 

 in proportion to the grate surface than is found in ordinary 

 tubular boilers. 



