LAVOISIER AND LAPLACE. 557 



which would raise 150 Ibs. of water 70. Now 

 if we suppose that 45,000 cubic inches of oxy- 

 gen are consumed by a healthy man in 24 hours, 

 making about 2 Ibs. in round numbers; and 

 that 40,000 cubic inches, or a little more than 

 1 Ib. 12oz. are expired in the form of carbonic 

 acid, it must unite with about 12 oz. of carbon ;* 

 so that if the same proportion of caloric be given 

 out as in ordinary combustion, it ought to com- 

 pensate the loss of 52^ in a man weighing 

 150 Ibs. And if the remaining 5000 cubic inches 

 of oxygen combine with ^th its weight of hydro- 

 gen, (we have seen that the proportion of oxygen 

 which disappears is generally much larger in 

 carnivorous animals,) it ought to raise the tem- 

 perature of 150 Ibs. of water 12; allowing, with 

 Dr. Thomson, that caloric enough is evolved 

 during the combustion of 1 Ib. of hydrogen to 

 melt 400 Ibs. of ice. 



Lavoisier and Laplace inferred, from their ex- 

 periments, that during the combustion of 1 Ib. 

 of charcoal, caloric enough was evolved to melt 

 96 Ibs. of ice ; and that nearly the same amount 

 was given off by animals in proportion to the 



* Dr. Dalton calculated that the aliment which he took in 24 

 hours contained about 11| oz. of carbon; but that the mean 

 quantity exhaled from the lungs did not exceed 10| oz. ; the 

 remainder passing off with the other excretions. He thinks that 

 of the 6 Ibs. of food and drink taken daily by a healthy man, 

 1 Ib. consists of carbon and nitrogen, the remainder being chiefly 

 water. (Manchester Memoirs, Vol. II. N. Series; and Ed. New 

 Phil. Journal, 1832, 1833.) 



