228 IOWA ACADEMY OF SCIENCES. 



valleys are connected by narrow gorges. Abrupt escarpments 

 form one side of the lateral valleys and long back-slopes the 

 other. A series of gigantic steps are formed. The idea is best 

 expressed by a cross-section (figure 4), which is a diagrammatic 

 one, of the same region in which the photograph was taken. 



Fig. 4. Cross-section of the Crimea. 



In this country we have some excellent examples of this type 

 of topography. Besides the great areas in southwest United 

 States, the Black Hills and Ozarks furnish excellent examples, 

 but they are all on such a large scale that the camera cannot 

 satisfactorily reproduce them. Nowhere in this country is it 

 depicted so beautifully as in the region photographed. The 

 photograph was taken from the crest of one of the lofty escarp- 

 ments, just outside of the southern gates of the ancient city of 

 Chufut Kaleh, formerly occupied by the Karaim Jews, but long 

 since deserted and now in ruins. This point is about five miles 

 from Bakhchisarai, 300 years ago the capital of the Tartar 

 Khans, and about forty miles from Sevastopol. The resistant 

 numbers of the couplets forming the escarpments are chalky 

 limestones of Cretaceous age. To the north they are covered 

 by Tertiary deposits. 



In Iowa we have traces of an excellent illustration of Cuesta 

 topography, in the area occupied by the upper coal measures of 

 the southwestern part of the state. It is best shown, perhaps, 

 in Madison county. Elsewhere it is greatly obscured by heavy 

 drift deposits, which almost completely bury the highest escarp- 

 ments. Only here and there do the latter peep out through 

 the glacial debris. The broad, intervening valleys that once 

 existed are filled by surface deposits to a depth often of i!00 

 feet. 



