OF THE MOSSES AND THEIR ALLIES. 
153 
between the sheets of paper, are saved from the wear and 
tear to which they would be subjected if constantly brought 
out for investigation. 
I am of opinion, that if the specimens were mounted in 
silicate of potash (or waterglass, as it is sometimes called), 
much future time and trouble would be saved, as the leaf 
would probably retain its fair appearance without being 
immersed in water every time it was wanted. But my 
own experience is not sufficient to justify me in recom- 
mending it to others. [I have frequently employed silicate 
of potash as a preservative medium for the leaves of 
Mosses and other objects. In some instances it has suc- 
ceeded thoroughly, the leaflets retaining their fresh appear- 
ance, and remaining unaltered. But it appears to be un- 
certain in its action, 4 vacuoles ’ and bubbles often appear- 
ing in its midst in the most unaccountable manner. For 
pleasantness in using, rapidity in drying, &c., it surpasses 
any medium with which I am acquainted. — Ed.] 
