( 416 ) 



- = 0.89 X 10'. 

 m 



3. Hydnxjen (85.0 Kilogram, 9°.5 C.) /• = 456 y^K)-' 



cUldn (1 atm., 0° C.) = iO' 



(85.0 KG„ 9°.5 C.) = 1.31 X ^0% 



- = 1.77XiO". 



m 



4. Water. From refractive indices of Dui'et ^) and the magnetic 

 rotation constant O'. 01 30 we get 



- — 1.25 X iO'. 



5. Carbon dlsidphlde. In the same way with y z= 0'.042 we 

 find from van der Willigen's ^) refractive indices 



- = 0,745X^0'. 



m 



6. Quartz. y^O. 01684 ^). By means of \ an deu Willigen's refi-ac- 

 tive indices we find 



- = 1.25X10'. 



m 



e 

 It may be remarked that the \ahies of — found here correspond 



/// 



in order of magnitude with those IuiumI in other wavs. 



1) DuFET. Bull. Soc. Miner. cS p. ^18. 



2) V. D. WiLLiGEX. Arch. Mus. Teyler 111. 1. p. 55. 



3) BoREL, G. R. 1^28, p. 1095. 



(January 24, 1903). 



