438 Researches upon the Heat developed 



alcohol which is found in one pound of this hquid ; then 

 ^|-:-f4-J-8-=67'558 pounds, which is the measure of ihe heat 

 developed in the combustion of one pound of pure alcohol 

 of Lowilz, according to the mean result of the experiuK-nts 

 made with spirits of wine. 



In two experiments made with common alcohol, T had 

 for the mean result 54*218 pounds of water boiled ; and as 

 this alcohol contained 0-8057 pound of pure alcolu)!, this 

 will give for the measurement of the heat developed in the 

 combustion of one pound of pure alcohol of Lo'.vitz -g-.V^-ry 

 = 67*293 pounds of water heated 180^ Fahrenheit. 



In three experiments made with alcohol jt 42** which 

 had a specific gravity of =817624, I had as the mean re- 

 sult 61-952 pounds of water heated 1S0° F. with the heat 

 developed in the combustion of one pound of this liquid. 



According to this result, one pound of pure alcohol of 

 Lowitz ought to lurnish a sufficiency of heat in its com- 

 bustion to raise the temperature of 67-37 pounds of water 

 to 180= of Fahrenheit, for it is ^}^-i=QT\o\. 



On taking the mean between the results of the eight ex- 

 periments which were made with these three alcoholic li- 

 quids, we shall have for the measure of the heat developed 

 in the combustion of one pound of pure alcohol of Lowitz, 

 67-317 pounds of water at the temperature of freezing 

 carried to ebulliiion. 



It will be very interesting without doubt to know if this 

 quantity of heat agrees with the quantities of combustible 

 matters (carbon and hydrogen) which exist in this alcohol : 

 this is precisely what we shall see. 



According to the analysis of M. de Saussure, one pound 

 of alcohol of Lowitz contains 



Carbon 0-4282 pound 



Free hydrogen 0' 1 1 8 



Water 0-4700 



Now, according to the estimate of Crawford, we shall have 



Pounds of Water heated 

 to 180" Fahrenheit. 



For the measure of the heat in the combus-l c<±.rc^ ika 



tion of 0-4282 pound of carbon j " 



And for the measure of that which is fur- 



nished in the combustion of 0-1018 pound V4I'738lbs, 

 of hydrogen J 



Total 66-405 



The experiments yielded 67'3I 7 



It is rare in so delicate an investigation to find so perfect 



an agreement between the results of the experiments and 



those of the calculation. 



