National Institute of Informatics - Digital Silk Road Project
Digital Archive of Toyo Bunko Rare Books

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quite near us; a little north branch of the river sweeps immediately along the foot
of the rocks; the road is here laid with stones and protected by a low stone wall.
The valley and mountain of Changri are left on our right.

We now come up on the hills of gravel and shingle, the foot of which is
washed by the Tsangpo, making the slope very steep down to the river. It is on
the top of this terrace we again camp at Ta-nakpo. The brook Ta-nakpo-chu had
now diminished considerably, to about 5 cub.m., which chiefly seems to depend on
the irrigation canals, many of which now stood filled with water from the brook.

Both on my journey down to Shigatse and back to Ye the weather was very
windy: hard, westerly wind especially from noon till late in the evening. Riding
westward one had this wind straight in the face, and even with well protected eyes
it was sometimes impossible to look up. From higher points, as Lamo-tang, the
whole valley seemed to be filled with a compact yellow stream of drifting sand-
clouds, rushing down over the river-bed to the east. No doubt this annual sand-
loaded wind is one of the causes of the general barrenness of the valley. Sand-dunes
are also a common phenomenon, and only occasionally does the meagre vegetation
get time to bind them. The wind is a second agency assisting the river to work
out the valley. The great difference of temperature between winter and summer,
day and night, the capillar frost, the barrenness of the rocks, the rains, — everyone
of these agencies accelerates the weathering and decomposition of the mountains.
The finest detritus is carried away by the wind, and the corrosion of the drifting
sand again attacks the hardest rocks. Sand-dunes are formed on the level bottom
of the valley, and even between the river-branches. During the high-water season
they are again carried away and form new sand-banks lower down the course.
These sand-banks get transformed into new dunes. Thus there is a constant wandering
of solid material down the valley under the action of wind and water, both tending
eastwards. The air, the water, and the solid material, everything is wandering from
west to east through this great furrow between the Himalaya and Transhimalaya.
From the side-valleys much material is also brought down into the Tsangpo valley;
but the tributaries are protected against the wind. The Tsangpo is the great com-
mon recipient for wind, water and detritus. In the side-valleys the action of the
water is nearly at rest in winter, but in the Tsangpo valley the water always carries
out its work, though, of course, on a much greater scale in summer than in winter.

At Karu, on March 30th, I was told that the windy season would continue
for another two months. About the middle of May the wheat and peas are sown,
and the barley some 10 days later. When the crop is about 3/4 foot high, the
wind has ceased. At the end of June or in the beginning of July the rain sets in,
and during the rainy season there is no wind. The amount of rain varies year by
year, sometimes it falls in abundance, sometimes only in light showers, and much
interrupted by clear weather. In the middle or end of September the harvest is
brought in. Just now, or at the end of March, the frozen stretches of the river