Chemical Effects of 'Caloric, S?c. 71 



part of it freezing and gradually increasing in 

 the congelation. All this time the water con- 

 tinues at thirty-two degrees, which is perhaps 

 one or two above the temperature of the air to 

 which it is exposed. Now since it is known 

 that if a colder body is applied to a warmer it 

 will soon become of the same temperature, what 

 prevents the water from becoming of the same 

 temperature with the air to which it is exposed? 

 It is doubtless owing to the caloric, which had 

 been latent, emerging and becoming obvious or 

 sensible as soon as any particle of the water 

 freezes ; and as soon as this is all exhausted, the 

 mass becomes solid, and of the same temperature 

 with the air. The quantity of caloric which thus 

 emerges when a fluid body passes into a solid 

 state might be estimated, if the temperature of 

 the air would continue the same for a sufficient 

 length of time. From all this it is plain that the 

 combination of a certain portion (or dose, in the 

 chemical language, ) of caloric with ice turns it 

 into water, and the removing or taking away of 

 that portion of caloric converts it again into ice. 

 Thus water is a compound of ice and of caloric ; 

 and indeed all fluids are combinations of the 

 solid, and a certain dose of caloric. The quan- 

 tity of caloric necessary to render ice at 32 v 

 fluid is 14-0. 



There were disputes in Fahrenheit's time about 

 the rarefaction of ice, whether it depended on 

 the air contained in it during its fluidity. He 



