318 SALMON I A. 



Congelation expels both salts and air from 

 water, whether existing below, or formed in, 

 the atmosphere ; and in the high and unin- 

 habited regions of glaciers, there can scarcely 

 be any substances to contaminate. Removed 

 from animal and vegetable life, they are 

 even above the mineral kingdom ; and though 

 there are instances in which the rudest kind 

 of vegetation (of the fungus or mucor kind) 

 is even found upon snows, yet this is a rare 

 occurrence; and red snow, which is occa- 

 sioned by it, is an extraordinary and not a 

 common phenomenon towards the pole, and 

 on the highest mountains of the globe. 

 Having examined the water formed from 

 melted snows on glaciers in different parts of 

 the Alps, and having always found it of the 

 same quality, I shall consider it as pure 

 water, and describe its characters. Its colour, 

 when it has any depth, or when a mass of it 

 is seen through, is bright blue ; and, accord- 

 ing to its greater or less depth of substance, 

 it has more or less of this colour : as its in- 

 sipidity, and its other physical qualities, are 

 not at this moment objects of your enquiry, 



