and in the Condensation of Vapours. 4 1 3 



We shall now see what is the- highest temperature 

 which it would be possible to attain by burning char- 

 coal, and by blowing the fire with pure oxygen gas. 



According to Crawford, i pound of charcoal gives 

 heat sufficient in its combustion to raise the temperature 

 of 57.608 pounds of water 180 F., or to raise the tem- 

 perature of 9369,44 pounds of water i degree. 



Now, as i pound of charcoal is united to 2.5714 

 pounds of oxygen in burning, and forms with it 3.5714 

 pounds of carbonic acid, the heat which is found in 

 3.5714 pounds of carbonic acid at the instant of its forma- 

 tion would be sufficient to raise the temperature of 

 9369.44 pounds of water i degree ; consequently the 

 heat which is in i pound of this acid at the moment 

 of its formation would be sufficient to raise the tempera- 

 ture of 3643.6 pounds of water i degree. 



Here we have the quantity of heat which exists in the 

 carbonic acid at the instant of its formation. In order 

 to know what is the intensity which it would indicate 

 if we could measure it at this moment by means of a 

 thermometer, it would be necessary to know precisely 

 the specific heat of the carbonic acid. If, with Crawford, 

 we take it at 1.0459 ( tnat f water being taken = i), 

 we shall have 3811 F. for the measure of the intensity 

 of the heat which exists in the carbonic acid at the 

 moment of its formation, and consequently for the 

 intensity of the greatest fire made with charcoal (without 

 mixture of hydrogen), even in the case where the fire is 

 fed by pure oxygen. 



It remains to determine the temperature which we 

 might hope to obtain by burning charcoal with atmos- 

 pheric air. 



As we have found that the temperature of the 3.5714 



