104 IOWA ACADEMY OB^ SCIENCES 



As further evidence of this rapid change in the land 

 position with reference to the sea- level in very recent 

 times, Prof. (1. F. Wright, who has lately returned from 

 the same region, informs me that during his ti'ip he found 

 on the south shore of the Euxine, near Trebizone, espe- 

 cially, gravel beach-deposits at an elevation of nearly 

 700 feet. 



Now the great interest in these observations lies in the 

 fact that the region occupied by the Black sea is a part of 

 that wonderful belt of depressed crust which bisects the 

 Eurasian continent and which extends the whole length 

 of the Mediterranean sea, through the Black and Caspian 

 seas, the Sea of Aral, to beyond Lake Balkash. The sur- 

 face of the Caspian is nearly 100 feet below general sea- 

 level. The country on the north side of the Caucasus, 

 between this body of water and the Black sea, is scarcely 

 200 feet above sea-level at its highest point. 



Altogether, this region is perhaps the best we know of 

 for studying through the means of exact data, problems 

 of differential elevation of the earth's crust. 



