tainly seemed to be on a level with the path along
which we were marching, and the river is perhaps only
seen as an accidental item in the picture. When, however,
it is perceived running close under our feet, the
inference that it has to make its way up hill to fall
into the lake is, I suppose, irresistible. In any case, it
is a curious spectacle, and one to which Manning
evidently referred in his journal, though he must have
misread his notes. He records this optical illusion as
visible in Red Idol Gorge. The Kala tso, on the banks
of which the column halted for the night of the 6th,
after a short march, is the remains of a very much larger
lake, which in earlier days covered the whole plain that
now lies east of its shore. The scenery was the same
as before, though the scanty grass bents now become
a little more frequent, and thick wormwood appeared
here and there in patches on the mountain-side.
The most remarkable thing here is the evidence
of a very large population in earlier days which the
continuous string of ruined walls and houses supplies.
For a space of nearly two miles the hill-side road-—
which clings still to the mountains in avoidance of the
now vanished lake— is marked by a wilderness of great
pebbles which have dropped from the walls and houses
of a lost civilization. The ‘ ground is still marked by
lines of crumbling structures held together in the
ground plan of their first shape by dry layers of mud-
mortar. Thousands must have lived here once. As
with most other things in Tibet, there are many different
reasons suggested for this wholesale desertion— a smallpox,
the subsidence of the lake, the Mongol invasion,
the utter inability of the inhabitants to adjust themselves
to so wretched and inhospitable an environment.
Perhaps, also, the closing of the trade routes over the
Sikkim passes may have had their effect. It is only
clear to-day that the scanty duffle-clad figures who
bow with protruded tongues at the entering in of their
hamlets and the black-aureoled women whose heads
appear inquisitively over the sordid sod-parapets of
the roofs above are but the hundredth part of the population
of a scattered but important trade centre in the
past.
From Menza, where the column halted on the night
of the 7th, the long-deferred descent on the northern
side of this vast water-shed begins, and with it the
course of the Nyang chu. This stream does not run
from the Kala tso, as is represented by many maps.
It rises in a full head of water that breaks from under
an old glacier bed which fronts the eastern end of the
Kala plain, and flows with an even and increasing
current in a northerly direction. The plain which has
to be crossed before Menza is reached is the last of the
long, dreary plateau which begins 50 miles back at
Kamparab, and though later in the year purple vetches
flourish, they barely dissemble the utter barrenness of
the long, dry, dreary road. All this plateau is 15,000
feet in height. Vegetation of any height greater than
that of a brush or wormwood is impossible, and the
continued absence of trees, to those accustomed to the
vegetation of England or India, is wearisome in the
extreme.
On the night of the 8th of April, the camp was pitched
upon a projecting tongue of land which juts out with
steep cliffs between two beds of the upper waters of the
Nyang chu. Away to the south and south-east the
great icy barrier between Bhutan and Tibet rose high
v o l . 1. 1 1 *