Organic Matter found in Sulphureous Springs. 593 



be embarrassed to account for the fact he states, of his having 

 met with it in the thermal waters of Ischia, or even in those 

 temporary springs which are caused by the condensation of 

 the steam disengaged from Vesuvius*. 



I have myself collected the water emitted from the spiracles 

 of several volcanos, as at -^tna, Volcano, and the Solfatara of 

 Puzzuoli ; and have remarked, that it was in general perfectly 

 pure, with the exception of a slight impregnation either of sul- 

 phuretted hydrogen, sulphureous, or muriatic acid, and that it 

 was entirely destitute of any ingredient to which an animal or 

 vegetable origin could be ascribed. 



The deposition of zoogene therefore, in such situations, must 

 be supposed, as it may be without difficulty, to have arisen 

 from the rapid generation of certain Oscillatoria or other living 

 bodies allied to them, owing to the temperature and chemical 

 constitution of the water derived from this source being favour- 

 able to their existence. 



To show the impossibility of supposing the organic matter to 

 have been disengaged, according to Professor Anglada's notion, 

 from a state of chemical solution, I may mention, that at Aries 

 in Roussillon (the thermal water already alluded to), it occurs 

 in great abundance, adhering in flakes to the rock, with which 

 the hot spring comes in contact on first issuing from the earth : 

 now this rock is inclined at so high an angle, that a substance 

 deposited by the water could not possibly have adhered to its 

 surface, but must inevitably have been washed down into the 

 reservoir below, which receives the runnings from the spring, 

 where, however, comparatively little of it is to be found. 



On the other hand, it is not more difficult to account for the 

 growth of organic bodies in such a position, favoured, as it is, by 



* Bibliotheque Universelle, torn. xi. p. 410. He supposes the animal matter to be 

 carried up along with the steam in a state of vapour. 



4 G 2 the 



