OF ARTS AND SCIENCES. 



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in diameter and 23 cra high, rests upon a tripod. In its interior is a 

 three-way stopcock, communicating with the small interior vessel B, 

 the vessel A, and the vulcanite spout C. By turning it, the vessel B 

 could he filled with water, and its temperature measured by the ther- 

 mometer D, after which it could be delivered through the spout into 

 the calorimeter. As the vessel B, the stopcock, and most of the spout, 

 were within the vessel A, and thus surrounded by water, and as the 

 vulcanite tube was very thin, the water could be delivered into the 



calorimeter without appreciable change of temperature. The proof 

 of this will follow later. 



The calorimeter, E, was of very thin copper, nickel-plated very 

 thinly. A hole in the back at F allowed the delivery spout to enter, 

 and two openings on top admitted the thermometers. A wire attached 

 to a stirrer also passed through the top. The calorimeter had a 

 capacity of about three litres, and weighed complete about 388.3 

 grammes. Its calorific capacity was estimated at 35.4 grammes. It 

 rested on three vulcanite pieces, to prevent conduction to the jacket. 



