252 Mr. S. S. Richardson on Magnetic Rotary 



In the following table the infra-red values are those of 

 Rubens, whose values are reduced by *0011 in order to bring 

 them into line with those of Simon. 





XxlO 4 . 



n (obs.). 



ii (calc). 



Diff. 



•2981 



1-5861 



1-5856 



-5 





•3081 



1-5751 



1-5750 



-1 





•3133 



1 5701 



1-5702 



4-1 





•3261 



1-5596 



1-5598 



4-2 





•3404 



1-5501 



1-5502 



+ 1 





•3467 



1-5464 



1-5465 



+1 



fc 



•3613 



1-53905 



1-53905 







o 



•4340 



1-5154 



15154 







w 



•4678 



1-5089 



1-5087 



-2 





•4800 



1-5069 



1-5068 



-1 





•4861 



1-5059 



1-5059 









-.1086 



1-5030 



1-5028 



— 2 





•5349 



1-4999 



1-4998 



-1 





•5893 



1-4950 



1-4949 



-1 





•6563 



1-4908 



1-4907 



-1 





•768 



1-4860 



1-4860 









•823 



1-4857 



1-4846 



0(-ll) 



£T 



•878 



1-4845 



1-4833 



-1 



7 



•940 



1-4834 



1-4822 



-1 





1012 



1-4822 



1-4811 







?s 



1096 



1-4808 



1-4801 



4-4 



p. 



1-195 



1-4795 



1-4791 



4-7 



CO 



55 



1-316 



1-4784 



1-4783 



+ 10 





1-461 



1-4775 



1-4775 



4-11 





1-645 



1-4768 



1-4784 



f27 



1-881 



1-4760 



1-4760 



+ 11 



From Rubens' values Martens deduces X^'1366. But 

 this value is clearly much too small, the differences for *3403, 

 •3261, -3133, -3081 being respectively —16, —33, —56, and 

 — 69. Martens assumes a — 0, c' = 0, and takes a x -= 1*1724. 



The sudden bend in the experimental curve in the region 

 of \= 1*645 is doubtless due to selective dispersion produced 

 by the band observed by Coblenfcz at 1*7 //,. Similar but 

 smaller fluctuations appear in the experimental curve for 

 benzene, for which substance Coblentz has recorded weak 

 bands at *8/u, 1*0, 1*4, and 1*7. 



Naphthalene Bromide, 



The liquid used was a specimen of a-monobromnaphthalin, 

 supplied by Kahlbaum as pure, and carefully redistilled. 



