DR. BREWSTER ON REFLECTED LIGHT. 
199 
Names of Oils. 
Image at the Surface of Prism A. 
Image at the 
Surface of Prism B. 
Oil of Bergamot . . < 
Three very fine orders. First limit at 73°. Heat spoils] 
first order. J 
Yellowish white. 
Oil of Beech Nut 
' Three excellent orders, and well defined. First limit at 
73°. Heat spoils first order. j 
• Yellowish white. 
Spermaceti Oil . . . . ■ 
'Two tolerable orders. First red and blue bad, second red] 
and blue good. First limit at 73°. J 
Yellowish white. 
Oil of Olives .... 
Three good orders. First limit at 73°. 
Whitish yellow. 
Three o-ood orders. First limit at 73°. 
Grayish white. 
Whitish yellow. 
Oil of Rosemary . . 
Two good orders and more. First limit at 73°. 
Oil of Poppy . . . . 
r Three excellent orders. First limit at 73°. Heat injures 
[ the colours. j 
■ Yellowish white. 
Oil of Lavender . . < 
' Three good orders. First red and first blue very fine. 
First limit at 74°. 
> Yellowish white. 
Oil of Camomile . . < 
Two good periods. First limit about 60°. 
Bright yellowish 
white. 
Oil of W ormwood . ■ 
'Three good periods. First limit at 71°, but not well 
[_ defined. 
> Yellowish white. 
Bhela .Tiiirfi < 
’ Three faint orders at low temperatures, but finely brought " 
\ 
> Yellowish white. 
out by heat. First limit at 73°. 
Muriatic Acid .... 
Traces of tints. 
Yellowish white. 
Sulphuric Acid .... 
Two pretty good orders. 
Yellowish white. 
Vitreous Humour of 
the Haddock . . . . ^ 
- Traces of colours. 
Bright. 
Oil of Rhue 
No colours. 
Bright. 
Bright. 
Oil of Boxwood . . 
No colours. 
Alcohol 
Traces of reddish, bluish, and greenish yellow tints. 
Traces of tints. 
Bright. 
Bright. 
Water 
The experiments * recorded in the preceding pages may be divided into two 
classes. 
I. Those which establish the existence of reflecting forces at the confines of 
media of the same refractive power ; and, 
* These experiments have been extended to a great number of mixed oils and to soft solids, gums 
and resins, combined with the prisms A and B. I have also substituted for these prisms others of 
different kinds of glass, which give similar results ; and I have examined the phenomena at the con- 
fines of different fluids and a great number of minerals of various refractive powers between chromate 
of lead and fluor spar. 
