HUDSON AND MOHAWK DISTRICT. 
267 
One pint gave 8 grs. solid matter, consisting of 
Chloride of sodium._ 1 *042 
Sulphate of lime_ 1*816 
Sulphate of magnesia- 4*116 
Carbonate of lime_ 0*620 
7*594 
Hydrosulphuret of magnesium and organic matter, 0 • 406 
8*000 
The quantity of gas remains undetermined, and it is assumed that the combination is as I 
have here stated. A small quantity of sulphur is deposited upon the stones and other 
substances over which the water flows. 
The large bodies of water which are collected in reservoirs formed in the rocks belonging 
to the Champlain division, are generally soft, and quite free from mineral and organic 
matter. We have an illustration of this fact in the water of Lake Champlain. It gives 
only a faint cloud with nitrate of silver, and scarcely a perceptible precipitate with chloride 
of barium ; hence there is almost a total absence of the chlorides and sulphates, bodies 
which most usually exist in hard or mineral waters. This is accounted for by the purity of 
the waters which supply the lake. Most of the rivers and streams rise either in the Primary 
region, or in the hard shales of the Primary and Taconic system of Vermont. The drains 
from the Tertiary clay upon its border scarcely affect the great mass of the water forming 
the body of the lake. 
34 
