29S Researches upon the Heat developed 



placed in the receiver of the calorimeter (inchiding the 

 quantity of this liquid which represents the specific heat of 

 the instrument) ; and a lighted taper having been placed at 

 the mouth of the worm, the calorimeter was heated for 

 ] 3 minutes and 26 seconds. When the thermometer an- 

 nounced that the water had acquired the temperature of 

 66° F. the taper was extinguished. 



As I took care to weigh the taper before lighting it; on 

 weighing it again at the end of the experiment, 1 found 

 that r63 gramme of wax had been burnt. 



In order to express the results of this experiment in a 

 way to render ihem palpable, and at the same time easy to 

 be compared with the results of other similar experiments, 

 we shall show how much water at the freezing point, the 

 heat manifested in the combustion of 1*G3 granmie of wax 

 which were burnt, must have boiled under the mean pres- 

 sure of the atmosphere. 



The interval upon the scale of Fahrenheit's thermometer, 

 between the freezing and boiling points, being 160 degrees; 

 if, in order to raise the temperature of the water in the ca- 

 lorimeter 10 degrees, we must burn 1'63 gramme of wax, 

 29'34 grammes must be burnt in order to raise it ISO de- 

 grees: and if 29*34 grammes of wax can furnish a suffi- 

 ciency of heat in their combustion to raise the temperature 

 of 2781 cranunes of water 180 degrees; one gramme of 

 the same flammable substance ought to furnish enough to 

 heat 94-785 grammes of water the same number of de- 

 grees. 



Consequently, one pound of while wax, or of a taper 

 which we burn, ought to furnish in its combustion enough 

 of heat to raise 94*785 pounds of water from the freezing 

 to the boiling point. 



In order to ascertain how many pounds of ice the same 

 quantity of water would be capable of melting, we have 

 only to add to the number of pounds of water at the tem- 

 perature of ice which this heat is capable of boiling, the 

 third part of this number, and the sum will express the 

 weight in pounds of this quantity of ice*. 



For while wax therefore — 9i'785 

 4-31-595 



= 1 26-380 pounds of thawed 

 ice for one pound of the substance burnt. 



* It is known that the same quantity of heat •which is necessary for 

 tnehing one pourid of ice, would be suflicieut for heating and boiling three 

 ^luriers of a pound of water at the temperature of ice- 



Before 



