io 4 



Of the Management of Fire 



to boil with i Ib. of fuel. Hence it appears that the 

 expense of fuel was greater in this experiment than in 

 that last-mentioned. 



Again, in the Experiment No. 3 1 , when no less than 

 11,368 Ibs. or 1685 gallons of water were heated and 

 made to boil in the new brewhouse boiler, the wood 

 consumed amounted to 650 Ibs., which (as the tempera- 

 ture of the water at the beginning of the experiment 

 was 65^) gives for the precise result of the experiment 

 14.59 Ibs. of ice-cold water made to boil with the heat 

 generated in the combustion of i Ib. of the fuel. 



As the relative quantities of fuel expended in the 

 experiments are inversely as the numbers expressing 

 the quantities of ice.-cold water, which, from the result 

 of each experiment, it appears might have been heated 

 1 80, or made to boil, under the mean pressure of the 

 atmosphere at the level of the sea, with the heat generated 

 in the combustion of i Ib. of the fuel, it is evident that 

 these numbers measure very accurately the different 

 degrees to which the economy of fuel was carried in 

 the different experiments. The economy of fuel in 

 heating liquids, depending on the quantity of the liquid, 

 as shown by the foregoing experiments, may therefore 

 be expressed shortly in the following manner : 



