BURIED CITY OF TAKLA-MAKAN 803 
mous carrying capacity. During the other months of the 
year the wind blows less frequently and with greater 
variableness. On January 25th, with a tolerably strong 
south-west wind, I found that the crest of a sand-dune 
travelled 4 ^ inches to the north-east in the space of forty- 
five minutes. The wind changed in the night, and the 
top of the dune then returned to the south-west, travelling 
35f inches in nine hours. Assuming that in every year 
there are on an average twenty-four days in which the 
wind blows with hurricane violence towards the south-west, 
and that on each such day it blows almost uninterruptedly, 
so that a sand-dune will travel six to seven feet, it would 
travel altogether about 160 feet in the course of the year, 
and would therefore require a thousand years to reach the 
point at which the desert sand has now arrived in its 
journey towards the south. At the same time, it must be 
borne in mind that I have assumed the greatest possible 
number of burans in the year, and hence have obtained 
a minimum estimate for the ag'e of the city. Then again 
the sand-dunes do not move directly south, but to the 
south-west, a circumstance which increases the probable 
age to some 1500 years. Finally we have to take into 
account the less violent wind which blows in the opposite 
direction ; which probably adds yet another five hundred 
years to the age of the city. But I shall be able to 
return to this subject at greater length, and with exacter 
data, after I have worked out the meteorological observa- 
tions which I brought home with me. We may further 
pretty confidently assert, that the inhabitants of the town 
were Buddhists and of Aryan race. Perhaps it is they 
who have given rise to the many legends about the people 
Tokta-rashid Nokta-rashid, against whom Sultan Arslan 
(Ordan Padshah) is said to have fought. It may be that 
this city flourished at the same period as Borasan. 
At this point I may perhaps conveniently interpolate 
a few facts about the individual sand-dunes. The base 
is originally half-moon shaped, with the convex side 
gently sloping to the windward, and a concave steep side 
to leeward. At each end in the direction of the wind 
