hether, in the former case, the ice was black and sound or
that dread element, water, was rippling against the runners. If so, out
came the clasp-knife, and there was no more _koshma_ for that night.
During the first week we frequently passed places where hot springs had
broken through the ice. One or two of these holes were quite near the
track, and might well, on a dark night, have brought the expedition to
an untimely end.

Talking of ice, we noticed a curious phenomenon in connection with it
while journeying down the Lena. On clear sunny days the frozen surface
of the river would appear to be sloping downwards at a perceptible
gradient in the direction in which we were travelling; occasionally it
would almost seem as though we were descending a fairly steep hill, had
not the unrelaxed efforts of our teams suggested the optical delusion
which, as long ago as 1828, was observed by Erman the explorer, who
wrote: "I am disposed to think that this phenomenon was connected with
the glistening and distortion of distant objects which I remarked not
only in this part of the valley, but frequently also on the following
days. This proved that the air was ascending from the ice and therefore
that the lower strata were lighter than those above in which the eye was
placed. Under such circumstances a plane perfectly horizontal and level
in fact would appear depressed towards the horizon, or, in other words,
it would seem to slope downwards." Scientists must determine whether
this be the correct explanation of this strange deception of nature,
which was often noticeable on the Lena, although we never observed it
elsewhere.

We reached Ust-kutsk (the first town of any importance) on the sixth
day. This place figures largely on most English maps, but it is little
more than an overgrown village. A church with apple-green dome and gilt
crosses, a score of neat houses clustered around the dwelling of an
_ispravnik_,[9] perhaps a couple of stores for the sale of clothing and
provisions, and a cleaner post-house than usual: such is a "town" on the
banks of the Lena. With the exception of Ust-kutsk there are only three,
Kirensk, Vitimsk, and Olekminsk, places of such little general interest
that they are chiefly associated in my mind with the four square meals
we were able to obtain during those three weeks of incessant travel. At
Ust-kutsk, for instance, we refreshed the inner man with a steaming bowl
of _schtchi_ or cabbage soup followe