On Mud Volcanoes and Salt Lakes in the Crimea. 417 



supply, although the oil was several feet deep in the bottom of 

 the first well. 



In the case at present before us (Girjarva) the interest is 

 greater than at Boulganak, inasmuch as the extinct mud- 

 volcano, the active little craters around the oil-well, and an 

 entire village, are all contained within the hollow of one large 

 crater, of which one side (that to the south) is capped with 

 limestone, from underneath whose beds springs of tolerably 

 pure though rather saline water issue. The level of the bottom 

 of this larger crater, which is open on one side (towards the 

 north), and which is remarkably regular, is about 100 feet 

 above the sea, as measured by an aneroid barometer under cir- 

 cumstances not very favourable. Sulphur springs come out to 

 the south in a small valley removed from the crater by limestone 

 hills. That the Lake Tchokrak already described is a similar 

 crater, at a lower level, and in which the supply of water has 

 been kept up, but which is also due essentially to volcanic 

 agency, I have no doubt. It is only in this way, I believe, that the 

 peculiar nature of the waters and mud can be accounted for. 



Another curious and much larger lake of the same general 

 nature, and due to similar causes, is about twelve miles south 

 of Girjarva, and is called Tchongolek or Tobetchich. Like 

 Tchokrak it is rounded in form, although a kind of inlet creek 

 running to the west, in a direction opposite to the sea, gives it 

 a peculiar form. It resembles very closely the shape of a pear. 

 It is separated from the Black Sea by a low narrow causeway, 

 a hundred yards or so across. The level of the small lake of 

 Tchokrak is much lower than that of the Sea of Azof. Tchon- 

 golek is also lower than the Black Sea, but the difference is not 

 great. Estimated by a good aneroid under favourable circum- 

 stances, it was not more than five feet. This is caused by 

 evaporation, as there is no communication with the sea. 



Like Tchokrak the waters of Tchongolek are very salt, and 

 the mud intensely black and sulphurous. Both water and mud 

 are somewhat less rich in products. On one part of the shore 

 of the lake is every appearance of a crater, but the rock is here 

 a marly limestone inclined at a very high angle (nearly 80°), 

 and a little beyond is a string of old Tatar wells, and a num- 

 ber of recent sinkings and borings for petroleum. Some of the 

 sinkings have been successful. There are salt works on this 

 lake on a somewhat large scale, but here as at Tchokrak the 

 sun is the only evaporative agent. Another salt lake is passed 

 on the coast between Girjarva and Tchongolek, and there are 

 several between the latter and Kaffa. 



Crossing the Straits of Kertch we reach several low strag- 

 gling fingers of land that project from the most westerly spurs 

 of the Caucasus towards the Crimea. Between them is the 



VOL. VIII. — NO. VI. EE 



