国立情報学研究所 - ディジタル・シルクロード・プロジェクト
『東洋文庫所蔵』貴重書デジタルアーカイブ

of harzburgit in 24°N.40°E., but amongst the detritus one finds granites, gneiss,
crystalline schist and other specimens generally rounded by the waves. At the
western side of the promontory the harzburgit dips 76°E., and still farther west
47°E. A narrow valley opens to the bay west of the promontory and here is a
road from Purang; a caravan of sheep, just passing here, came from Purang and
was on its way to Lumaring-tso and Kerki in the interior of Western Tibet. The
valley was called So-longyo, though this name is doubtful.

Then follow some small bays and promontories and finally a large, not very
deep bay, before Camp 227 is reached at the very point of a sharp, rocky peninsula.
The rock is the same harzburgit as before, now in 41°N.2°E. N.N.E. and not far
from the shore is a little rocky island, Lache-to. It takes only 25 minutes to walk
round the island along its shore. It consists of solid rock rising steeply from com-
paratively deep water, or 34.5m., halfway between the island and Camp 227. The
rock of the island consists of the same harzburgit in 38°N.40°E. At the foot of
the rock are heaps of detritus and sometimes more or less well developed terraces.
The north-eastern part of the island forms an open plateau, and here, amongst sand,
gravel and vegetation, the wild geese breed in spring and early summer as could be
seen from thousands of eggs. The people of Parka plunder the nests of the wild
geese every spring, and reach the island on the ice, which indicates that at least
this more protected part of the lake remains frozen rather long, say six months. A
little ring wall also proves that the island is occasionally visited.

The section of the shore from Camp 227 to 228 is also very irregular, for
the mountains of the southern shore send forth a series of ramifications and spurs
forming promontories and peninsulas. In each bay between them a valley or ravine
is formed, sometimes with terraces, seldom with a minimal brook, which disappears
into the gravel before it reaches the shore. These little valleys seem to be very
short, and there is hardly room for any considerable length, as the great Purang
valley is near at hand on the southern side of the ridge.

Following this shore one has a feeling of being in a labyrinth between water
and land. The perspective is very picturesque and changes every moment. One
has a series of promontories westwards and understands that each of them is
situated between two bays. A terrace follows the foot of the rocks; it is exactly
10m. high (August 30th), and at Camp 227 it was 48m. from the shore; some-
times it is interrupted or disturbed. The same harzburgit rocks continue the
whole way, in 73°N.45°E., 48°N., and 40°N.70°E. The two islands are easily
visible in the south-western corner of the lake, but one can only seldom make out
that they are real islands and not parts of promontories. There may possibly be
three of them. The greatest is called Dopserma, though other Tibetans called
it Dotser.

One promontory could be cut off in a pass about 100m. above the lake.
West of it is a long narrow bay. At the sides of a valley coming out here, per-