( 



III. Corresponding Degrees in the 

 Fahrenheit and Centigrade 

 Scales. 



9 ) 

 IV. 



Fahr. 



212-0 



208-4 



204-8 



201-2 



197-6 



194-0 



190-4 



186-8 



183-2 



179-6 



176-0 



172-4 



168-8 



165-2 



161-6 



158-0 



154-4 



150-8 



147-2 



148-6 



140-0 



136-4 



132-8 



129-2 



125-6 



122-0 



118-4 



114-8 



111-2 



107-6 



1040 



100-4 



96-8 



93-2 



89-6 



86-0 



82-4 



78-8 



75-2 



71-6 



68-0 



64-4 



60-8 



57-2 



53-6 



50-0 



46-4 



42-8 



39-2 



35-6 



32-0 



28-4 



24-8 



21-2 



17-6 



14-0 



10-4 



6-8 



3-2 



- 0-4 



- 4-0 



Hefractive Indices, Dispersi-7-e 

 Powers, and Polarizing 

 Angles. 



(1.) Repeactiye Indices. 



Diamond 



Phosphorus 



Bisulphide of carbon 



Flint glass 



Crown glass 



Kock salt 



Canada balsam 



Linseed oil (sp. gr. - 932) 



OU of turpentine (sp. gr. - 885) 



Alcohol 



Sea -water 



Pure water 



Air (at 0° C. 760 mm.) 



(2.) DispEESiVE Powers. 



Diamond 



Phosphorus 



Bisulphide of carbon 



Flint glass 



Crown glass 



Eock salt 



Canada balsam 



Linseed oil (sp. gr. -932) 



Oil of turpentine (sp. gr. - 885) 



Alcohol 



Sea water 



Pure water 



Ail- 



(3.) PoLAEizixG Angles. 



Diamond 



Phosphorus 



Bisulphide of carbon 



Flint glass 



Crown glass 



Rock salt 



Canada balsam 



Linseed oil (sp .gi-. -932) 



on of turpentine (sp. gr. -886) 



Alcohol 



Sea water 



Pure water 



Air 



P< 



c3 



