9 9 



H. XAGAüKA. 



I 11 i)l)S(,'r\ iiiLi' I'ix'sirTs (litfractiiju phcuoincii;!, tlic ()pli(';il Ijcncli 

 was used. The iiitcr\:ils Ijctwccu the fringes were measured by iiieau« 

 of ;i iiiierometer. The iollowing table _ii'ives the observed uuiidjers. 



R^= 324.0, E'^= 285.4 mm.' 

 26 = 0.347; ;i = O.00048() mm. 



