Determination of Energy Dissipated in Condensers. 223 



through its walls, and (2) to carry away and measure all heat 

 generated within by a stream of water To effect the first con- 

 dition two concentric copper walls (the lining and the jacket) 

 are maintained as nearly as possible at the same temperature. 

 This, of course, will reduce the flow of heat through the inter- 

 vening wooden wall to a minimum, and make the " cooling 

 correction " small, if not zero. 



(i r> 



1 



To Eliminate the Cooling and Capacity Corrections. 



In order to ascertain any difference of temperature between 

 the copper walls a and b, a differential air-thermometer is 

 used. Each air-chamber of this differential thermometer 

 consists of a copper pipe about 4 metres long and 4 millim. 

 internal diameter, one coiled about and soldered to the lining, 



