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BOILER TESTS. 

 Results of Tests, Boiler No. 14. 



The tests on Boiler No. 14 like those on No 13, were made 

 to determine the effect produced by two widely different rates 

 of combustion. In Test No. 31 the rate was 11.4 pounds of 

 coal per square foot of grate per hour, and in Test No. 32 it 

 was 6 pounds, one giving a somewhat larger amount of power 

 than the rated boiler power, and the other a much lower 

 amount. The economical result obtained with the low capac- 

 ity is the better of the two to the extent of 4.2 per cent. 

 There is a noticeable difference in the two tests in the tempera- 

 ture of the escaping gases, one being 476 and the other 380 

 degrees. To this difference is evidently due the comparatively 

 low economy produced by the rapid combustion. Comparing 

 these results with those obtained from Boiler No. 13, they are 

 inferior, as might be expected from the difference in the quan- 

 tity of heating surface, and the resulting higher temperature of 

 the waste gases. There is 20 per cent, less heating surface in 

 proportion to grate in this boiler, than in Boiler No. 13. 



