DESERTS. 251 
THE NORTHERN PAMIR. 
GREAT FEATURES OF THE PAMIR. 
As a general key to what has been happening in the mountains, the Northern 
Pamir with its border ranges stands paramount. On a map of Asia it appears 
as a massive knot of intersecting ranges, where high members of the Tian Shan 
system conflict with a northwestern extension of that immense plateau of moun- 
tains called Tibet. Offhand, we should expect to find a heavy precipitation of 
snow upon such a high uplifted mass. But looking down upon it in reality we 
behold a desolate expanse of barren clay and stone, with only here and there 
a small white blotch of snow, and some few desert lakes; a very high plateau 
crisscrossed by mountain ranges inclosing a multitude of broad barren steppes 
that sweep in graceful curves from range to range. While some of these are trav- 
ersed by streams, many of them are undrained depressions with or without lakes. 
We look upon a vast, extremely arid wilderness, void of trees and almost without 
any vegetation; a nude expanse of gray desert steppes and worn-down mountains 
with many-colored cliffs, of which the higher rise to white-crusted domes of ice. 

Fig. 431.—Lake Kara Kul (North End). 
This remarkable aridity is perhaps the most emphatic demonstration of 
Central Asia’s isolation from moisture. In the Pamir we have a region whose 
depressions lie from 13,000 to 15,000 feet above the ocean, and whose mountains 
rise to from 18,000 to 24,000 feet in height. Similar latitudes elsewhere record 
a snow-line of 10,000 feet elevation, but now we are dealing with an interior region 
surrounded by the greatest mountains and deserts of the world. It is, therefore, 
logical to find the snow-line at 16,000 feet with Sven Hedin’s report of less than 
1-inch precipitation over Kara Kul, the salt lake of its widest basin. The Southern 
Pamir is less arid, as it receives about all the precipitation of southern winds 
left after the Hindu-kush and Karakoram have had their share. 
THE BASIN OF GREAT KARA KUL. 
The basin of Great Kara Kul was studied on two expeditions; the first in 
1903, under the auspices of the Carnegie Institution of Washington, the second 
in 1904, an independent exploration, from which much of my data on other regions 
will be drawn. And though the basin has been discussed in my first year’s report 
some repetition is important for the sake of correlation. 
