UPON THE DIFFERENTLY COLOURED RAYS OF LIGHT. 5 
It acts less powerfully upon the green rays than crown- 
glass. 
5. Acid, Muriatic. 
Muriatic Acid acts much more ee upon green light 
that flint-glass. 
It acts more powerfully upon. green light than crown-glass. 
It acts less powerfully upon green light than rock-crystal. 
It acts less powerfully upon green light than water. 
It acts very much less powerfully upon green light than sul- 
phuric acid. 
6. Acid, Nitric. 
Nitric acid acts much more powerfully upon the green rays 
than flint-glass. 
It acts a little more powerfully upon the green rays than 
crown-glass. 
It acts much less powerfully upon. the green rays than sul- 
- phuric acid. 
7. Acid, Nitrous. 
Nitrous acid acts much.more powerfully upon green light 
than flint-glass. 
It acts less powerfully upon green light than topaz. (Nota. 
good observation.) 
It acts less powerfully upon green ight than rock-crystal. 
It acts less powerfully upon green light than nitric acid. 
It has nearly the same action upon green light as crown- 
glass; an uncorrected green fringe appearing towards the 
vertex of the nitrous acid prism, when it is inclined to the in- 
‘cident ray, and, towards the vertex of the crown-glass prism, 
when it is placed first, and-inclined to the incident ray. The 
fringe is, however, greater in the latter case, and therefore the 
acid 
