B8 Inquiry concerning the Nature of Heat, 



The quantity of surface by which this vessel was ex- 

 posed to the cold air was = 74.5581 superficial inches, 

 exclusive of its neck, which was well covered up with 

 fur. 



The quantity of surface which was exposed to the air, 

 in the foregoing experiments with the conical vessels, or 

 the area of the bottom of each of the vessels, was (4 X 

 3.14159) = 12.4263 superficial inches. 



As the diameters and heights of the conical and cylin- 

 drical vessels were equal, the contents of the former 

 must have been to the contents of the latter .as i to 3 ; 

 and the quantities of heat which they lost in cooling 

 were as their contents. 



If now the cylindrical vessel lost a quantity of heat 

 = 3 in 23} minutes, it would have disposed of a 

 quantity = i (equal to that which the conical vessel 

 lost) in one third part of that time, or in 7 minutes 

 and 50 seconds. 



But the quantity of surface exposed to the air in the 

 experiment with the cylindrical vessel was to that so 

 exposed in the experiment with the conical vessel as 

 74.5581 to 12.4263, or as 6 to i. 



Now, as the time in which any given quantity of heat 

 can pass out of any closed vessel into or through any 

 cold fluid medium by which the vessel is surrounded 

 must be inversely as the surface of the vessel, other 

 things being equal, if a quantity of heat = i could 

 pass out of the cylindrical vessel in 7 minutes and 50 

 seconds, it would require 6 times as long, or 47 min- 

 utes, to pass out of the conical vessel through its flat 

 bottom^ supposing no heat whatever to escape through 

 the covered sides of that vessel. 



If now the whole of the heat which the conical vessel 



