408 NOTES ON THE GEOLOGY 



establishment there for warm baths. Another salt and hot spring 

 exists near Khoy. Surely, in springs so numerous, which must 

 nearly all flow into the lake, we have a prolific source of the less 

 abundant ingi-edients of that lake, although it is true that these 

 springs have not been analyzed. But we know that they are 

 carbonated and sulphureted springs, and probably they contain 

 ingredients similar to springs of the same general character in 

 other parts of the world. 



I would here remark, that, in the facts above stated, we see the 

 probable origin of the saltness of many of the lakes of Central 

 Asia. The whole of that vast region appears to have been more 

 or less subject to volcanic action ; and as one of the results, a 

 vast amount of chloride of sodium and other salts, has been pro- 

 duced. Oroomiah is thus rendered too salt for any sort *of an- 

 imals to live in its waters : though, from the fact that the flamin- 

 go is very commonly found wading along its shores, I strongly 

 suspect that some sort of worms is found in the mud beneath 

 the waters. But the Caspian is far less salt, and furnishes fine 

 fish in abundance. The same is ti'ue of lake Van, which lies 

 west of Oroomiah, and is of about the same size. In lake El- 

 ton, and some others in Asiatic Russia, already mentioned, the 

 principal ingredient is chloride of magnesium, to which cncum- 

 stance Prof. Daubeny attributes tlie precipitation of rock salt 

 upon their bottom. 



I have received no specimens from the vicinity of the Caspian 

 Sea, except No. 552, from its shores. This sand is chiefly mag- 

 netic iron ore : but it contains also, manganese, and grains of 

 oUvine. This last mineral shows that the region around must 

 contain volcanic rocks. 



I ought to state, that the water from lake Oroomiah, whose 

 analysis has been given above, was obtained about the twentieth 

 of September, from the north end of the lake. A specimen re- 

 cently brought by Mr. Perkins, whicli was procured near the city 

 of Oroomiah on the first of July, that is, when the lake must 

 have been miich higher than in September, has a specific grav- 

 ity of 1114, considerably less than that of the former, indicating 

 the presence of a less quantity of salt ; which is what we should 

 expect. 



