294 Researches upon the Heat developed 



of the air was only a few degrees hiaber than that of ice 

 (a circumstance with which I cannot be acquainted), ihe 

 quantity of azote which must have entered into the calori- 

 meter with the oxygen emploved to keep up the combus- 

 tion, is so great, that it would be sufficient to account for 

 tlie difference ; but the very great difference which exists 

 between the results of our experimenis made with oil of 

 olives, proves that one or oiher of our processes must have 

 been faulty. 



§ II. Heat developed in the Combustion of Olive Oil. 



The mean result of several experiments made with oil of 

 olives gave me as the measure of the quantity of heat de- 

 veloped in the combustion of one pound of this substance, 

 90*439 pounds of water heated l&rj^ of Fahrenheit, or 120 

 pounds of dissolved ice, omitiing fractions. 



In the experiments of M, Lavoisier there were upwards 

 of 148 pounds oi ict di.sfolvtd by ihe heat which appeared 

 to result from the combustion of one pound of this oil. It is 

 true that this excellent experimenter has himself regarded 

 this result as too great, and he adds with becoming mo- 

 desty, "We shall probably be obliged to make considerable 

 corrections in most of the results which 1 have given ; but: 

 I dil not cosider this a good reason lor delaying to assist 

 those who may purpose to engage in sinuiar inquiries." 



§ III. Heat developed in ihe Comlnstiofi oj piirified Oil rf 

 Colsci, such as that which is sold in Paris Jor Lamp Oil. 



As it appears very probable that all the lat oils which are 

 perfectly pure, are composed of the same elements, I was 

 anxious to know if oil of colsa, purified with sul[)huric acid, 

 would not give out more heat in its combustion than oil of 

 olives when burnt in its natural state. The results of three 

 experimenis made with purified oil of colsa, convmced me 

 that in fad this oil gives more heat in its combustion than 

 olive oil : the difference is even considerable, and more than 

 I had suspected. 



With the combustion of one pound of refined oil of 



colsa 93-073 pounds of water heated ISO", 



one pound of olive oil 90*439 ditto ditto. 



Chemists are best qualified to inform us if the quantity 

 of incombustible matter separated from the oil of colsa, in 

 refining it, be sufficient to account fortius difference. 



On comparing the results of the experiments made with 

 bees wax with those of purified oil, it seems that, the weight 

 being equal, these two substances furnish in their combus- 

 tion 



