744 
THROUGH ASIA 
they could conveniently carry on their riding-horses, or 
peasants travelling from one oasis to another, sometimes 
driving in front of them a few donkeys laden with seed 
or vegetables. 
Like all the oases along this route, Ak-lengher was 
situated by the side of a watercourse going from the 
south to the north ; but it very seldom contains water, 
only in fact after heavy and continuous rains in the 
mountains. The oasis depends for its supply upon a 
well sunk 126 feet down through the clay. This 
formation, yellowish - brown in colour, contains sprink- 
lings of rounded, polished stones, not exceeding two 
inches in diameter, and consisting partly of hard, fine- 
grained, blue-black slate crossed by delicate white veins, 
and partly of red and greenish-grey granite. The well 
is cleaned out two or three times a year ; for lumps of 
clay fall in from the sides and stop the inflow of the 
water. A man is let down with a rope tied round his 
body, the other end of which is drawn across a horizontal 
roller resting on two short posts at the top. The mud 
and sludge are sent up in a wooden bucket, and emptied 
out all round the well mouth. The top of the well is 
protected against the sandstorms by a wooden roof, 
provided with a hatch or flap. At half-past three in the 
afternoon the temperature of the water at the bottom of 
the well was 55° Fahr. (i2°79° C.), whilst the temperature 
of the air was 37°2 Fahr. (2°9 C.) at 4.30 p.m. The water 
was saline, with a bitter flavour, and undrinkable except 
with tea and sugar. In this connection I may mention 
that the well at Kizil (between Yanghi-hissar and Yarkand) 
was 1 19 feet deep, and that its water was sweet, with a con- 
stant temperature of 59°9 Fahr. (i5°5 C.). The inhabitants 
however, misled by the alternations of the temperature 
of the air, asserted that in summer the water is cold, but 
in winter warm. 
January 6th. After riding about 4^ miles (nearly 
two potais) we came to a belt of sand-dunes, high and 
continuous, in the middle of which there was a ridge of 
clay, with some poplars growing on it, and poles with 
