TOPOGRAPHICAL OUTLINE OF ASIA. 275 



we should expect to be very largely guided in our conclusions by the facts 

 there presented. What we have first to do, in pursuing- our inquirj^ over the 

 Asiatic region in accordance with the order followed in the present chapter, 

 is to show where and under what conditions ice and snow occur at the pres- 

 ent time over the various divisions of that continent; and that this nia}- be 

 done understandingly it will be desirable, as a preliminary, to give a rapid 

 sketch of the topographical features of the great Asiatic land mass, with 

 especial reference to those conditions likely to affect the amount and char- 

 acter of the pi-ecipitation so unequally distributed over its surface. Imper- 

 fectly known as portions of Asia still are, it is believed that enough has been 

 found out with reference to tlie topography and climatology of that country 

 to enable us to deal with the most general and important questions arising in 

 this connection. 



The continent of Asia may be considered, from the most general point 

 of view, as made up of two parts — a central elevated portion, and a lower 

 region — both of which cover areas of enormous extent, as compared with the 

 entire land mass of the globe. The higher region is soon perceived, on ex- 

 amination, to be made up of a series of high plateaux, each framed in by a 

 border of mountain chains. These table-lands are so closely connected with 

 each other, and the various lofty ranges which encircle them so linked to- 

 gether, that the whole stupendous mass of mountains and plains can hardly 

 be looked upon otherwise than as forming a geographical unity. Indeed, the 

 name " High Asia," in which term far the larger portion of the elevated 

 mass of the continent is comprised, is already current among geographers. 

 The Iranian and Arabian plateau S3'stems, with their enclosing and bordering 

 ranges, spreading themselves to the westward in Asia Minor, are so closely 

 compacted with High Asia by inosculating chains of mountains, that the 

 entire complex is clearly seen to belong together, and to form the central 

 nucleus, which, stretching from the Red Sea to the Northern Pacific, or from 

 southwest to northeast, constitutes by far the grandest highland system 

 of the world, of which the mountain regions of Europe are in reality but 

 diminutive appendages. 



Of the Arabian and Iranian table-lands and mountain chains we have 

 nothing to say in this connection, since they are not sufficiently elevated 

 to reach the region of eternal snow. Their increasing dryness has already 

 been the subject of comment in the preceding chapter. Of two mountain 

 ranges, however, one of which is entirely isolated from the elevated central 



