74 Of the Management of Fire 



as that of beech, when the quantities, estimated by weight, 

 are equal. 



In the Experiment No. 6 it was found that 43 Ibs. of 

 dry beech-wood were necessary when used as fuel, to 

 prepare 89 Ibs. of peas-soup. In the Experiment No. 7, 

 the same process was performed with 37 Ibs., and in the 

 Experiment No. 9 with 39 Ibs., of dry pine. But I shall 

 have occasion to treat this subject more at length in 

 another place. In the mean time I would, however, 

 just observe, that all my experiments have uniformly 

 tended to confirm the fact that dry pine-wood affords 

 more heat in combustion than dry beech. I have 

 reason to think the difference is in fact greater than 

 the experiments before us indicate ; but the apparent 

 amount of it will always depend in a great measure on 

 the circumstances under which the fuel is consumed, 

 or, in other words, on the construction of the fire-place ; 

 and it is no small advantage attending the fire-places I 

 shall recommend, that they are so contrived as to in- 

 crease as much as it is possible the superiority of the 

 most common and cheapest fire -wood over that which 

 is more scarce and costly. 



By comparing the results of these two sets of Experi- 

 ments (Nos. 7 and 8, Nos. 9 and 10), an estimate may be 

 made of the advantage of using very dry wood for fuel, 

 instead of making use of wood that has been less thor- 

 oughly dried ; but, as I mean to take an opportunity of 

 investigating that matter also more carefully hereafter, I 

 shall not at present enlarge on it farther than just to 

 observe that as the wood, which was dried in an oven, 

 was weighed for use after it had been dried, and as it 

 certainly weighed more before it was put into the oven, 

 the real saving arising from using it in this dried state 



