246 



ELEMENTARY CHEMICAL MICROSCOPY 



Table IV. 



MEDIA FOR REFRACTIVE INDEX DETERMINATIONS. 1 



For the lower ranges of refractive indices the following mixtures have been found 

 to be satisfactory. The components being: Acetone, n = 1.358; Petroleum, 

 n = 1.443; Turpentine, n = 1.474. 



'These mixtures were determined experimentally in the Department of Chemistry, 

 Cornell University, by Mr. C. W. Mason. Above n= 1.45, Wright's Series Table II, should 

 be used. 



