1 72 Dr. Hare on the Construction and Applications of the 



are attached. The lower ends of the wires, within the tube, are 

 made to communicate by means of a fine platina wire fastened 

 to them by solder. 



Fig. 5. '^ 



The apparatus being so far prepared, let it be firmly fixed 

 over the pneumatic cistern, so that the water may rise about 

 an inch above the lower extremity of the tube. To the gallows 

 screws gg, attach two leaden rods, severally proceeding from 

 the poles of a calorimotor. By means of a leaden pipe, pro- 

 duce a communication between the bore of the cock and an 

 air-pump, so that by pumping the air from the cavity of the 

 tube, the water of the cistern may be made to rise into the 

 space thus exhausted of air. On each side of the tube, and 

 between it and each iron rod, there is a strip of wood scored 



so 



