01<' STEAM AIMSING FROM BOILING SALT SOLUTIONS. 3 



riay-Lussac, as the editor of the Frcncli journal, appended a note 

 to tliis paper, in Avhich he first pointed out that facts similar to those 

 observed by Ftiraday had long been known in France, namely, that 

 when steam from boiling pn re water was passed into a cold concen- 

 trated solution (jf a salt, the latter could be heated up nearly to its 

 boiling point. Then, witli regard to Faraday's view that steam 

 generated from a boiling salt solution has only the temperature of 

 100^5 Gay-Lussac remarked : '* Sans irivoquer ici le secours de la 

 théorie, nous pouvons afiirmcr, d'après le iémoignage irrécusable de 

 l'expérience, que la temperature de la vapeur fournie par un li(|uide 

 quelconque, sons une pression quelconque, est exactement celle de la 

 couclie liquide immédiatement en contact avec la vapeur." 



Faraday then undertook more researches on this <|uestion, and in 

 the Quarlerly Journal of Science for 1823, he published the results of 

 his experiments, and stated that he had proved Gay-Lussac's asser- 

 tions to be correct, but that he had been astonished at the difficulty 

 of obtaining definite results. Only when he used a double-walled 

 vessel, which contained the experimental solution botli between the 

 Avails and also abfjAC them, only when he heated the thermometer 

 previously to a temperature higher than that of the boiling solution, 

 and only after repeated observations, had he been able to convince 

 himself that no anomaly existed in this j'henomenon. These experi- 

 ments of Faraday will be criticised presently along witli those of 

 MaQ:nus. 



Ivudberg (Ann. Chcm. Vhijs. [Vogi].\ 34, 257), in 1835, pul^Iishcd 

 the results of a long series of observations on the temperature of 

 steam evohed from difierent solutions, boiling under different pres- 

 sures, and pointed out that it is always the same as that of steam 

 arising from pure water l)oiling under the same pressure. Some of 

 his numbers are quoted below. 



