Return to Vienna. { 113 



the plains about the Caspian and Black Seas, in Asia Minor 

 and Mexico, it is found every where in analogous relations and 

 circumstances. Such are sands mixed with marie and argile ; 

 it is accompanied with several other salts, whereof the com- 

 mon sort is the most plentiful. There was a succession of 

 rainy weather which prevented my researches into other par- 

 ticulars, though my curiosity had been ardently excited. 



I spent one entire day in peregrinating the borders of these 

 lakes, but the earth was every where a flat surface, and there 

 was no ravine, to explore its composition in detail. Thoroughly 

 to investigate the phenomenon, it would be requisite to make 

 excavations, and examine such as have been made occasionally 

 in certain pits or wells. Ruckert, who for a long time was 

 employed in extracting the natron, and had leisure to explore 

 the soil, states- that the sands are not more than four or five 

 feet in thickness, and that they rest on a layer of blue argile, 

 and sometimes contain particles of iron in grain. He observ- 

 ed waters always lodging in the deeper parts, and therein Is 

 contained a great quantity of carbonate of soda, from 50 to 60 

 for the hundred, and which crystallises in the cold nights of 

 autumn. 



Not being able to remark on the saline efflorescence of the 

 soil or surface, where every thing was in a state of re-disso- 

 lution, I examined the natron that had been previously col- 

 lected. It was mixed with a pretty large quantity of grey ar- 

 gilous matter, and contained much muriate of soda, with a cer- 

 tain quantity of sulphate. I had afterwards an opportunity of 

 seeing some among the peasants in Great Cumania, collected 

 in the marshes that border theTheysse, and I noticed the same 

 salts, though in a less quantity. The same observation occurred 

 in the natron gathered in the plains about the lake of Nieusiedel. 

 I conclude that the carbonate of soda is never pure, but that in 

 Hungary, as elsewhere, wherever found, it is ever mixed with 

 muriate of soda, more or less. 



As to the origin of the natron, we have not data in a suffi- 

 cient number to pronounce on it with certainty. We are re- 

 duced to speculations which, as being founded on facts, inde- 

 pendent of any hypothesis, merit a degree of attention. With 

 respect to sub-carbonate of soda, to which Ruckert attributes 

 it, by a certain process of nature, this opinion rests on no 

 positive observations, as no excavations have been made, pur- 

 posely, for the sake of such. Nor is it in analogy with the 

 depots of rock-salt, ancient or modern, and the waters of otir 

 seas, which deposit salt on the shores, contain no trace ot it. 

 In this last case, there does appeal 1 , however, to be a form.a- 

 tion of natron, but in very small quantities, which effloresce 



VOYAGES and TRAVELS, No. L, VOL. IX. Q 



