Rotational Optical Activity in Isotropic Media. 1005 



more pronounced than the increase except when the density 

 of the absorbing molecules is small, when there is approximate 

 symmetry. This is in complete agreement with the experi- 

 mental results obtained by Cotton. 



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The relative absorption of the two rays is also increased in 

 the neighbourhood of the band, where it in fact changes very 

 rapidly. For small densities it is symmetrical on both sides 

 of the band, but for larger densities it may be of opposite 

 sign on the two sides. This would indicate opposite elliptical 

 polarization of a beam of light, according as its frequency is 

 just below or just above that of the absorption band. 



