and in the Condensation of Vapours. 423 



wise, in the 71.31 grammes of alcoholic vapour condensed 

 in the calorimeter, in the experiment in question. 



In order to simplify our calculation, and to render 

 our comparisons more striking, we shall show how much 

 pure water, in vapour, ought to have been sufficient to 

 furnish, in its condensation, the same quantity of heat 

 which was furnished by the condensation of 71.31 

 grammes of alcoholic vapour, in the experiment in 

 question. 



In this experiment the temperature of the calorimeter 

 was raised to i4|- of Fahrenheit. 



In the second experiment, made with the steam of 

 pure water, the temperature of the same calorimeter was 

 raised io^ of Fahrenheit, with the heat developed in 

 the condensation of 24.4 grammes of this vapour. 



Consequently the temperature of the calorimeter must 

 have been elevated to 14^ of Fahrenheit, with the heat 

 which must have been developed in the condensation 

 of 33-695 grammes of steam from pure water. 



Now, as the hydrogen and the oxygen forming the ele- 

 ments of 41.727 grammes of water, which are found to 

 form constituent parts of the 71.31 grammes of vapour 

 of alcohol condensed in the experiment in question, only 

 furnished in their condensation the same quantity of 

 heat as 33-695 grammes of steam of pure water should 

 have furnished, it is clearly proved, in my opinion, that 

 these elements are not so united as to form water, so 

 long as they concur in the formation of alcohol. 



I have discovered that the vapour of sulphuric ether 

 furnishes about one half less of heat in its condensation 

 than that of alcohol, and consequently one fourth only 

 of what is furnished by the steam of water of equal 

 weight ; but, having been interrupted by an accident in 



