ee a i 
Organic Matter found in Sulphureous Springs. 589 
Naturelle, may be seen figured an Oscillatoria, the filaments of 
which are disposed a good deal in the same manner; and 
Vaucher, in his work on Conferve*, has depicted, under the 
name of Oscillatoria major, an appearance very similar in kind 
to the cylindrical tubes detected by the microscope in my spe- 
cimen. Now this particular species of Oscillatoria is one of 
those found by Saussure in the hot springs of Aix near Cham- 
bery, occasioning there a deposit in the canals and cisterns 
of the baths, which, notwithstanding the explanation thus 
long ago afforded of it by the above able naturalist, continues 
even at the present day to give rise to much speculation and 
wonder. 
The mineral water of Greoulx resembles in constitution that 
of Aix, being a hot sulphureous spring, possessing a tempera- 
ture of 31° Reaumur, and containing, according to the Report 
published by the proprietor of the baths, the following saline 
ingredients in the pint. | 
Common salt. . . . . 12:25 grains. 
Muriate of magnesia . . 1°75 
Sulphate of lime . . . 1°66 
Carbonate of lime . . . 3°00 
Total... 4442-21800 
The quantity of organic matter present in the water of Greoulx 
is estimated in the above document at no less than 6:66 grains 
to the pint; but the greater part of this quantity must have 
been merely suspended in the water; for a portion of it, which 
I collected on the spot, being evaporated to dryness, gave but 
very feeble indications of ammonia, or of any animal or vege- 
table matter whatsoever. 
A substance altogether similar to that from Greoulx was found 
* Geneva, 1803. 
In 
