ioo Of the Management of Fire 



from this circumstance I shall prove that the new 

 boiler is better adapted for saving fuel than the old. 



By comparing the results of the experiments made 

 with the same boiler, but with different quantities of 

 water, we shall constantly find that the expense of fuel 

 was less in proportion as the quantity of water was 

 greater. In the Experiment No. 23, when 127 Ibs. of 

 water were used, the result of the experiment indicated 

 that no more than 12.74 Ibs. of ice-cold water could be 

 made to boil with the heat generated in the combustion 

 of i Ib. of the fuel used ; but in the Experiment No. 26, 

 made with the same boiler, but when 4 times as much 

 water was used, or 508 Ibs., it appeared from the result 

 of the experiment that 19.01 Ibs. of ice-cold water might 

 be made to boil with i Ib. of the fuel. 



Now, in the first set of the experiments we are com- 

 paring, as the quantity of water used (12,508 Ibs.) was 

 much greater than that used in the second set (8 1 20 Ibs.), 

 it is evident that, if the construction of the machinery 

 and the management of the fire had been equally perfect 

 in the two cases, the economy of fuel would have been 

 greatest where the largest quantity of water was used, 

 that is to say, in the first set of experiments ; but, as that 

 was not the case, it is certain that the boiler used in the 

 second set is better adapted to economize fuel than that 

 used in the first. 



But we need not go so far to search for proofs of that 

 fact. The result of the Experiment No. 31 is alone 

 sufficient to put the matter beyond doubt. In this ex- 

 periment, in which the quantity of water (though still 

 considerably short of that used in the former set of ex- 

 periments) was augmented from 8 120 Ibs. to 11,368 Ibs., 



