42 
MR. POWER ON THE ABSORPTION OF THE SOLAR RAYS, ETC. 
or into 
tan e— 
cos 0 
according as g 2 or 1 is substituted in the place of 
Si, 
s' 
The former is the expression which Mr. Green has obtained for contiguous gases, 
and is identical with that obtained by Fresnel by an interpretation of the formula 
tan (fl' + fl ) ’ ^ ie ^ attei ‘ i s identical with that obtained by Fresnel from the formula 
S X 14 ^ ^ ^ | 
sin(e + 0 j' According to the views of the present author, the latter will belong to a 
totally reflected ray whose vibrations are performed in the plane of incidence, and 
the former to a similar ray whose vibrations are at right angles to that plane. — This 
and the preceding paragraph were added April 2, 1854. 
