470 Inquiries relative to the Structure of Wood. 



between the nippers are carefully preserved, and weighed 

 at the close of the experiments, to determine precisely 

 how much of the wood has been consumed. 



An assistant keeps his eye constantly on the ther- 

 mometer attached to the apparatus, and announces the 

 moment when the water in the calorimeter has attained 

 a temperature as much higher than that of the room as 

 it was below it at the beginning of the operation ; and 

 the flame from the piece of wood then burning is imme- 

 diately blown out. 



The remains of the shaving are laid aside, to be after- 

 wards weighed with the other fragments. 



The water in the calorimeter was then stirred, by 

 shaking it, taking care to hold the instrument by its 

 wooden frame, and the temperature of the water was 

 minutely observed and set down in a register. 



An experiment of this kind usually occupies about 

 10 or 12 minutes, according to the nature of the wood 

 and the number of degrees to which the temperature of 

 the calorimeter is raised. 



I made choice of the birch for my first experiments, 

 because the texture of its wood is very firm and even, 

 and burns with a very regular flame. 



To give the details and their results in few words, I 

 have placed them together in the subjoined table. 



The calorimeter, with the water it contained, was 

 equal in capacity, as to heat, to 2781 grammes of water. 



