171 



bottles at the very source, which were sent, 

 along with the nourishing milk of the tree called 

 vaca, to Messrs. Fourcroy and Vauquelin, by 

 the way of Porto-Cabello and the Havannah. 

 This purity in hot waters issuing immediately 

 from granitic mountains is one of the most cu- 

 rious phenomena, which the two continents dis- 

 play*. How can we explain the origin of 

 the hydrosulphuretted gas ? It cannot proceed 

 from the decomposition of sulphurets of iron, or 

 pyritic strata. Is it owing to sulphurets of cal- 

 cium, of magnesium, or other earthy metalloids, 

 contained in the interior of our planet, under 

 it's rocky and oxidated crust ? 



In the ravine of the hot waters of Mariara, 

 amid little funnels the temperature of which 

 rises from 56° to 59°, two species of aquatic 

 plants vegetate ; the one is membranaceous, and 

 contains bubbles of air ; the other has parallel 

 fibres-}-. The first much resembles the ulva 

 labyrinthiformis of Vandelli, which the thermal 

 waters of Europe furnish. At the island of Am- 

 sterdam Mr. Barrow % has seen tufts of lycopo- 



* In the ancient continent warm waters equally pure are 

 found gushing out from the granites of Portugal, and those 

 of Cantal. In Italy, the Pisciarelli of the lake Agnano have 

 a temperature equal to 93° cent. Are these pure waters the 

 product of condensed vapours ? 



+ Conferva ? Jibrosa, laete viridis, fibris parallelis, indivisisj 

 apicem versus attenuatis, 



\ Voyage to Cochinchina, p. 143. 



