LATENT CALORIC OF HYDROGEN. 77 



that the volume and elastic force of both gases 

 are destroyed on assuming the liquid form. 



If equal volumes of all gases contained the same 

 quantities of caloric, as conjectured by Dr. Dai- 

 ton, we should have 37,334, as the amount of heat 

 disengaged from 1 Ib. of hydrogen, and 18,666 

 from the oxygen, or of 56,000, corresponding 

 with the difference between the specific gravity 

 of oxygen and hydrogen, which is as 1 6 to 1 (that 

 is, the volume of 1 Ib. of hydrogen is twice that 

 of 8lbs. of oxygen). In accordance with this 

 hypothesis, 1 Ib. of hydrogen should give out 16 

 times more caloric than an equal weight of oxy- 

 gen, coinciding with the difference between their 

 volumes. 



But as it will be shewn hereafter, that equal 

 volumes, of the compound gases, which have a 

 greater density than that of hydrogen, contain 

 more caloric, I shall assume for the present, that 

 1 Ib. of hydrogen contains 8 times more caloric than 

 1 Ib. of oxygen, corresponding with the difference 

 betiveen their atomic weights ; for it would be con- 

 trary to all analogy to suppose, that an atom of 

 hydrogen, which is only \ the size of an oxygen 

 atom, should contain double, or any other greater 

 quantity of caloric.* 



* It is therefore probable, that 1 Ib. of hydrogen evolves 28,000 

 of caloric during combustion, which would melt 200 Ibs. of ice at 

 32 and that 8 Ibs. of oxygen afford the same quantity. From 

 the large amount of caloric combined with hydrogen, we are en- 



