346 Mr. Take Sone on the Magnetic Susceptibilities 



The fact that the susceptibility of air directly determined 

 shows a close coincidence with the value calculated from the 

 susceptibilities of its constituent gases, proves not only the 

 correctness of the values of the susceptibility of each gas, 

 but also that the additive law holds for the susceptibility of 

 a gas mixture. Hence, in deducing the susceptibility of air 

 from that of oxygen, it is not correct to neglect the magnetism 

 of nitrogen and argon. The magnetism of these two gases 

 contributes about one per cent, to the total magnetism of air. 

 It has long been believed by many investigators that nitrogen 

 is paramagnetic, with the exception of Pascal * who obtained 

 a diamagnetic susceptibility for this element by an indirect 

 method. His value corrected for the susceptibility of water 

 is 



Xn = -0-397 x 10-*. 



The value is numerically greater than mine by 50 per cent. 



The susceptibility of argon in the present experiment is 

 obtained indirectly and therefore we cannot lay too much 

 weight on the value, and I hope to ascertain it by a direct 

 measurement. But it may be noticed here that by a direct 

 measurement P. Tanzler f found the susceptibility of argon 

 to be 



j^- -6-1x10-, 



in close enough agreement. 



The gaseous carbon dioxide has hitherto been believed to 

 be paramagnetic ; but on the contrary, it is diamagnetic. 

 The specific susceptibilities of solid and gaseous carbon 

 dioxide have almost the same value. 



The susceptibility of pure hydrogen gas which does not 

 contain oxygen by more than 1/150000 volume of hydrogen 

 is determined to be 



Xm 



= -l-98 2 XlO- 6 + 0'01 5 xlO- ( 



Among the values obtained by previous investigators, 

 those of Pascal % and K. Onnes and A. Perrier § are nearest 

 to the present value. As stated above, the value by K. Onnes 

 and A. Perrier was obtained for the liquid state, and more- 

 over, their determination was not very accurately made ; 



* P. Pascal, loc. cit. 



t P. Tanzler, Ann. d. Phys. Chem. xxiv. p. 931 (1907). The present 

 value is calculated from the original value by taking x = 104*1 xlO -6 . 

 % P. Pascal, loc. cit. % 



§ K. Onnes & A. Perrier, loc. cit, 



