RECONNAISSANCE IN CENTRAL TURKESTAN. l8l 
stream so large that it may be truly called a river. Tradition (the tradition found in 
almost every eastern country) says that this is the outlet of the inclosed lake Kara 
Kul, lying 75 miles to the southeast, on the Pamir, at an elevation of 12,400 feet. 
The chief interest of the Alai basin lies in its old moraines and terraces, which 
will be discussed in due season. Of the regions seen by the writer in the heart of 
Asia none is more interesting than the Alai Valley. Its magnificent scener>' and 
splendid climate on the one hand are only less excellent of their kind than are the 
opportunities for studying the epochs of the glacial period, tlie moraines and ter- 
races which bear witness to them, and all the phenomena pertaining to glaciation, 
past and present. Not far to the southwest the salt deposits of Altyn Mazar are 
of the first importance geologically and economically, and various natural sections 
present fine opportunities for the study of the rock series ; while to the southeast 
Peak Kaufmann rises 23,000 feet, with Lake Kara Kul on the Pamir beyond it. 
Moreover, the Alai Valley is inhabited by a peaceable and most interesting folk, the 
nomadic Kirghiz, with whom it is well worth while to become acquainted. Besides 
all this, the valley is relatively accessible, as it is only three days' journe)' from the 
railroad at Marghilan ; and, lastly, it is practically virgin ground. 
THE FERGANA BASIN. 
In outward appearance the last of the four provinces differs widely from its 
companion, the Kashgar basin ; but the difference is only superficial, resulting from 
its moister climate. The Fergana basin seems green and prosperous ; its many 
streams are utilized by an irrigation system which sustains populous villages and 
cities. The Kashgar basin is chiefly a drear}- desert. Yet in structure the two 
basins are so nearly identical that detailed description of the second would in\olve 
repetition of much that has been said about the first. The Fergana basin is an 
aggraded depression, due to local down-warping and burial of the Tertiary pene- 
plain. The mountains inclosing the basin are uplifted and more or less dissected 
portions of the same peneplain. As in the Kashgar basin, the warping by which 
the Fergana basin was formed seems to be a late phase of long-continued move- 
ments, during which the mountain area has encroached upon the basin area; for 
the gradually rising mountains around the basin consist of granite and limestone in 
their higher parts and of weaker Mesozoic and Tertiary strata around the margin next 
to the basin, all these having been folded and worn down to moderate relief before 
the present basin was formed. It is therefore quite possible that the down-warped 
floor, on which the Quaternary- deposits of the Fergana basin lie, was not ever}-- 
where a peneplain of Tertian,- erosion ; its central part may well have been an 
aggraded plain of Tertiary deposition. 
The periphery of the Fergana basin is sheeted with gravel which grows grad- 
ually finer until it merges into the fine alluvium of the central plain ; the area of fine 
alluvium is much smaller than that of Kashgar and has no pla)-as. Many streams 
cross the plain, with broad flood-plains of gravel between low terraces, while here 
and there rise hills more or less carved in masses of interstratified silt and gravel 
thrust up as folds in recent geological time. 
