AFGHANISTAN 67
of the Hindu Kush presents the aspect of a flattish-backed
watershed (often falling to less than 17,000 feet above
sea-level) with a surface scored by glaciers and indented
by lakes, which have been found wherever its highest
ridges have been explored. There is no continuous central
line of water parting such as is common to its spurs,
and in this particular it is not so perfect a natural boundary
 as would be offered by a more definite mountain
backbone.
From the point where the Sarikol dividing barrier
between Russia and China touches the Hindu Kush at its
junction with the great Muztagh barrier between India
and China, it becomes the southern boundary of Afghanstan,
 which territory lies between it on the south and the
ipper tributaries of the Oxus (or Panja) River on the
nrorth, Afghanistan thus stretches out a long arm to the
10rth-east from Badakshan, touching China at its farthest
sastern extremity, and preserving a narrow “buffer”
between Russia and India. This long arm is the Afghan
province of Wakhan, and it is worthy of note that at the
point where the Hindu Kush overlooks Kala Panja on the
Oxus, the northern spurs which comprise the full width of
Afghanistan intervening between Russia and India are
something less than ten miles in length, from summit to
base.
Before leaving the Pamir regions (to which we shall
10t again revert) to trace the Afghan boundary southwards
 a few words may be added about the source of the
Oxus. Many and various are the initial sources which
have been assigned by different authorities to this historic
river ; but (as often happens) the clearer light derived
from detailed survey proves them all to be more or less
incorrect. First in the historical list was Lake Victoria
(Wood's Lake), which lies near the head of the Great Pamir
drainage. Next perhaps in importance is Lake Chakmaktin,
 the lake of the Little Pamir, whence flows the
Aksu or Murghab River by a long and devious course to
the main stream of the Oxus. This is undoubtedly the
longest, if not the chief, tributary. Then we heard of the