PHILOSOPHICAL TRANSACTIONS. 



I. On tli,' Ift'frtirfioii <uul Dispersion of the Halogens, Halogen Acids, Ozone, 

 Steam, Oxides of Nitrogen and Ammonia. 



Hit ( 'I.IVK ( YTHIIKRTSON, l''<'ilir <>f I ' ,' > r, ,-^ity College, London Univerm/ >/. 



n,td MAUDE CUTHBERTSON. 



Communicated by A. W. PORTEK, F.H.*. 

 Received October 18, 1912, Read January 16, 1913. 



CONTENTS. 



Page 



INTRODUCTORY. 



Scope of research 



Expression of results : formula and its interpretation . . . 



Summary of results 



EXI'KKIMENTAI.. 



Measurements of refraction and dispersion 



Chlorine 



Standard conditions 



IT 



Bromine 



Iodine 



Hydrochloric acid 



Hydrohromic acid 



determination of density of I 3 



I n 



Ilydriodic acid 



determination of density of ; 



Steam . . . .' 



Ozone 



Ammonia 



AO 



Nitric oxide 



no 



Nitrous oxide 



98 



Errors of experiment 



05 

 Calculation of constants 



IT has long been well known that the refractive indices of simple gaseous compounds 

 do not obey the additive law so closely as those of solids or liquids. From the study 

 of these last GLADSTONE and DALE, and their followers, succeeded iu obtaining 

 refraction equivalents for a large number of the elements which were fairly constant 

 for the same class of compound. But in gases the discrepancies were found to be 



VOL. CCX1IL A 497. B Published separately, April 4, 1913. 



