420 On Mud Volcanoes and Salt Lakes in the Crimea. 



that when the wind blew from the north the discharge of mud 

 was greatest, and that when there was west wind more petro- . 

 leum was obtained from the wells. 



Besides the mud volcanoes and salt lakes already described, 

 a number of other salt lakes exist at various places round the 

 eastern part of the Crimea, both on the Sea of Azof and the 

 Black Sea. They are, indeed, repeated at intervals for a 

 distance of many hundred miles, and in most cases the mud 

 partakes of the peculiar qualities and properties described as 

 characteristic of Lake Tchokrak. The lakes as well as the 

 mud volcanoes occur in all cases in which I was able to examine 

 them in the highly-inclined strata underneath, and uncon- 

 formable to the limestone capping the hills. The exact age of 

 these it is not necessary here to determine, but there is clear 

 proof that all belong to the Tertiary period, and that the 

 elevations and movements have been continued and repeated 

 to the most recent times. The whole bed of the Black Sea 

 and the Sea of Azof along the broad line containing the mud 

 volcanoes and mineral springs, whether of water or oil, is still 

 in a state of upheaval, as proved by numerous examples of 

 raised beaches. 



The general conclusion to be drawn from the facts here 

 recorded is, I think, confirmatory of the opinion that mud vol- 

 canoes are due to causes not different in their nature from 

 ordinary volcanoes, though far less powerful in degree. This is 

 fully borne out by the condition of the salses of Central Italy. 

 In all of them volcanic forces of other kinds, and of greater 

 intensity, are, or have recently, been active in the immediate 

 neighbourhood. In some, as in the Crimea, there is still a certain 

 amount of force tending to upheave large tracts. But it may 

 still remain a question whether volcanic eruptions, exhibited 

 only by the thrusting out of slow torrents of cold mud, are due 

 to local causes, or are deep-seated and central. I think the facts 

 (1) that the volcanic axis is identical with the great elevation 

 axis ; (2) that the axis of the smallest and most recent action of 

 mud volcanoes is, in like manner, parallel to the most magnifi- 

 cent and important movements that have affected the surface 

 of the globe; (3) that chemical changes and results, mineral 

 waters, naphtha, and eruptions of various gases, are all 

 connected very directly with similar lines of action ; and (4) 

 that lines of fault, mineral veins, and certain systematic changes 

 that take place in the interior of the earth — are all suffi- 

 ciently indicative of a general causation, and afford satisfactory 

 evidence that continuous slow steady action in certain definite 

 lines is the law of nature, though occasional outbursts and 

 disturbances, comparatively very small, are also consistent 

 with this grand and majestic progress. 



