No. 149.1 183 



therefore, in reality, no received law to be set aside. That of 

 Guy Lussac remains unchanged, although restricted by the lim- 

 its of the experiments on which it is founded ; and any other law 

 determined by experiments beyond these limits, is not in opposi- 

 tion to, but an extension of his law. It has been considered 

 important that these fact should be stated, inasmuch as the in- 

 vestigations of Mr. Frost might be rejected without examination, 

 as contrary to a well established law of nature, were it not clear- 

 ly shown that tliis law has been too far generalized. 



By means of various apparatus, fully described in his pam- 

 phlet, Mr. Frost has obtained the following relations between the 

 volume, temperatures and tensions of steam, heated out of con- 

 tact with water: 



Temp. 



212° 



216 



228 . 



450 



600 



650 



"Whence it may be inferred that the volumes under the pressure 

 of a single atmosphere, and the tension under a constant volume, 

 would have borne the following relations to the temperature : 



The experiments of Mr. Frost have furnished, in his opinion, 

 complete proofs of the truth of the law of Mariotte, by means of 

 which the relations in the last table have been calculated. 



Mr. Frost next proceeded to measure the actual quantities of 

 heat contained in steam generated from water boiling under dif- 



