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 Confervce* , 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 •«■>'.''. 18-66 



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 



