ON THE CAPACITY FOR HEAT 



OR 



CALORIFIC POWER OF VARIOUS LIQUIDS. 



f B ^HIS subject is of rather an obscure nature, and it 

 JL has been so little examined, that it will be useful 

 to begin by elucidating it as well as I can. 



Let us suppose two cylindrical vessels, with very thick 

 sides, made of lead or any other metal, and perfectly 

 equal in size, each being capable of containing a pint. 



These two vessels being at the freezing-point, we 

 shall pour into the one a pound of water at the tem- 

 perature of 96 F. (= 28J- R.), being that of the 

 blood, and into the other a pound of olive oil at 

 the same temperature. 



Each of these liquids will heat the cold vessel in 

 which it is placed, the vessel in its turn will cool the 

 liquid, and both the liquid and the vessel will latterly 

 be of the same temperature. 



If water and oil of olives had the same calorific power, 

 a pound of water at the temperature of 96 would heat its 

 cold vessel precisely as much and not more than a pound 

 of oil would heat its vessel, the two vessels being of 

 the same weight and at the same temperature at the 

 commencement of the experiment. 



But experience shows that water heats its vessel much 

 more than oil does ; consequently the calorific power of 

 water is greater than the calorific power of oil of olives, 



