334 Mr. Take Sone on the Magnetic Susceptibilities 



paper, but the authors did not claim too much weight for 

 their result and were satisfied with the fact that their result 

 roughly agreed with the value obtained by Pascal. 



More recently Biggs* carried out the same investigation 

 of gaseous hydrogen. He tried to overcome the experimental 

 difficulties by utilizing the large absorptive power of 

 palladium for hydrogen, and found too large a value for the 

 susceptibility of the gas. 



The chief" difficulties met with in the determination of 

 gaseous hydrogen are two : the first is the preparation of 

 pure hydrogen free from oxygen, and the second the deter- 

 mination of the magnetic force exerted upon the gas, owing 

 to the smallness of its volume susceptibility and density. 

 In the present experiment these two difficulties were over- 

 come, and a highly trustworthy value for the susceptibility 

 of hydrogen gas was obtained. The details for the prepar- 

 ation of the pure gas and the determination of its magnetic 

 susceptibility are given in the following pages. 



(a) Preparation of pure Hydrogen Gas. 



In the present investigation the pure hydrogen was 

 prepared by the method which Morley | used in the deter- 

 mination of the volumetric ratio of hydrogen and oxygen in 

 water. The chief differences between his and the present 

 case were in the construction of the decomposing cell and 

 the combustion tube. In my case an open vessel was used 

 as a decomposing vessel, and platinum electrodes were 

 introduced into the cell by insulating the leading wires with 

 glass tubes. Oxygen which was generated at the anode, 

 was allowed to escape into the atmosphere. The electrodes 

 were separated from each other as far as possible in order to 

 lessen the diffusion of oxygen from the anode to the cathode. 

 The open end of the vessel was covered with a mica plate ; 

 besides, the upper portion beino;' wholly wrapped in cloth in 

 order to prevent any contamination of liquid. 



In the early period of the present experiment, I used for 

 a long time a combustion tube of hard j>lass, which contained 

 pieces of reduced copper gauze, both ends of the tube being- 

 ground and joined to the rest of the purifying train. But 

 in the course of the experiment it was found that in a long- 

 period of time the joints became gradually loosened by 

 repeated heating and cooling, allowing the diffusion of air 



* H. F. Bigga, Phil. Mag. xxxii. p. 131 (1916). 



f E. W. Morley, Amer. Journ. Sci. iii. xli. p. 220 (1891). 



