116 BOILEE TESTS. 



A comparison of these figures shows that the cost of making 

 a given amount of steam with chestnut No. 2 coal was 16 

 per cent, less than with stove coal, and the cost with the mix- 

 ture was 30 per cent. less. 



It is noticeable in the case of the test with mixed fuel that 

 the labor of firing was greater than that with either of the 

 other coals. There were 39 firings with the mixed fuel, 

 against 20 with the stove coal and 37 with chestnut No. 2 coal, 

 while the number of times the slice bar was used was 12 with 

 mixed fuel, and only one in each case with the others. 



The low temperature of the escaping gases is noticeable in 

 these tests. This is an indication of economical work which 

 the favorable character of the evaporative results plainly 

 bears out. 



Boiler No. 1 7. 



Kind of boiler, Horizontal return tubular. 



Number used, ...... Three. 



Horse-power (collective basis 12 square feet), One hundred and twenty-nine. 

 Age, Several years. 



Boiler No. 17 embraces three ordinary horizontal tubular 

 boilers set in brick work in the manner shown in the follow- 

 ing cuts. Two of these boilers are set with a furnace common 

 to both, and in all three the escaping gases, after leaving the 

 smoke arches in front, pass over the tops of the shells. The 

 three boilers are end boilers of the battery, and the next boiler 

 in the set was in daily operation during the progress of the 

 tests. 



