314 



Mr. Take Sone on the Magnetic Susceptibilities 



metal Q which can be moved smoothly along the axis of the 

 cup by means of: a screw E. To the left end of the cylinder 

 A, a brass piece B, and to its lateral surface, another piece D 

 is screwed in. The former piece is tightly connected with 

 the measuring tube, and the latter with the glass tube 

 forming the projecting neck of the compressing cylinder. 



Fig. 6. 



fW 



(Scale 1:1.) 



This connexion between the glass tubes and the brass pieces 

 is made airtight by sealing-wax mixed with a small quantity 

 of linseed oil. In order to prevent the flowing of wax into 

 the interior of the tube, when melted wax is poured into the 

 interspace between the brass piece and glass tube, a thin 

 rubber plate is placed at the end of the glass tube. All the 

 packings for the screws are made of thick lead plates. 



If the measuring tube with the brass pieces are connected 

 with the compressing cylinder by means of the screw D and 

 the inside air is evacuated by a pump connected with the 

 compressing cylinder, the piston P is displaced to the right 

 by a spring, so that the interior of the glass tube and of the 

 cylinder A communicate with each other. If after the gas 

 is compressed into the measuring tube, the screw E is turned 

 and the piston P made to press on the rubber plate, the piston 

 tightly closes the left hole of the cylinder A. The screw D 

 is then disconnected, and now the measuring tube with the 

 compressed gas inside can be suspended from the beam of 

 the magnetic balance between the pole-pieces of the electro- 

 magnet for the determination of the susceptibility of the 



