330 PICTURESQUE SKETCHES 



have been much visited, and are best developed in 

 those which are least accessible to scientific travel- 

 lers of the present day. 



Generally speaking, however, the continent of Asia, 

 like the greater part of Europe, must be considered 

 as of recent elevation. The broad tracts north of the 

 Himalaya chain, the district marked by the pre- 

 sence of extensive lakes on the European frontiers, a 

 considerable part of the peninsula of India, and pro- 

 bably the whole of Arabia, besides many at least of 

 the larger islands, are marked by the distinct pre- 

 sence of tertiary beds. These, however, exist in a 

 somewhat different condition from that observed in 

 Europe ; they often contain fossil remains of animals 

 totally different from European forms, but they still 

 approximate, and offer many interesting analogies on 

 a careful examination and comparison. It would be 

 unsafe at present to suggest what may have been the 

 actual history of the movements that formed the pre- 

 sent continent, and the order in which they occurred, 

 but we may at least give some sketch, which, however 

 it may hereafter need modification, will suggest ideas 

 and assist in the ultimate development of the subject. 



If we look at the map of Asia, and compare its 

 physical geography with that of Europe, it will not 

 be difficult to trace the relation of the great moun- 

 tain chains. The district, whose recent elevation in 

 Europe is marked by the Alps and the Carpathians, 

 is continued into Asia by the mountain chain of the 

 Caucasus, and is thence traceable till we reach the 

 Himalayas. Between these districts are spaces occu- 

 pied by the Black Sea and the Caspian, where the land 

 has probably only recently emerged from the sea. 



