on Magnetic Rotatory Polarization in Gases, 417 







Table 



(continued). 







Series. 



Average 

 tempera- 

 ture, t. 



Average 



pressure. 



H. 



Correction, 

 (1+O760 



Numbers 

 observed 

 and cor- 

 rections. 



Corrected 

 magnetic 

 rotations. 



Mean 

 devia- 

 tions. 



H 



July 24, 1880. 



M »> 



34-8 

 35-0 

 41-7 



GrREEN 



millim. 

 845-9 



847-2 



Blue 

 864-3 



LIGHT.— 4th 



1012 



3rd image. 

 1-012 



LIGHT. — 1st 

 1012 



image. 



42 / -41 

 Oorr. 6 13 



1 3671 

 L 29-51 

 I 15-34 



21 

 40 

 1-6 



Diff. 36-28 



34-07 



Oorr. 4-85 



Diff. 29-22 



image. 



17-75 



Corr. 2-58 



Diff. 1517 



By taking into account the 0*016 of air in the gaseous mix- 

 ture, we may calculate by means of the preceding numbers 

 the rotations that we should have with the gas absolutely pure. 

 We should find thus: — 



4th white image 29-90 



4th green image 37*19 



Olefiant Gas. — A preliminary series of experiments per- 

 formed upon a mixture of 0*72 of olefiant gas and 0'27 of 

 carbonic acid, proved that this body was endowed with a rela- 

 tively great magnetic rotatory power ; and we took extreme 

 precautions to obtain in the tube gas in its purest possible 

 condition. More than 300 litres of olefiant gas were passed 

 into the tube. This gas was prepared by the action of sul- 

 phuric acid on alcohol, purified from ether by passing through 

 sulphuric acid, and from the sulphurous acid (which was pro- 

 duced in rather large quantities) by passing through potash. 

 By remaining in the gasometer the gas became completely 

 freed from the small quantity of sulphurous acid which might 

 remain; but it was always mixed with a little air. 



The mixture was analyzed by passing a known volume of 

 the gas into a small graduated tube and then introducing 

 chlorine, bubble by bubble, so as to form ethylene chloride; 

 the excess of the chlorine was subsequently absorbed by potash. 



