reached the mouth of the Koyukuk on the 17th of
September and, having taken on board the supply of gasoline cached
there, turned our bow up the river the next morning. For five days we
pushed up the waters of that great, lonely river, and by that time we
were some twenty-five miles above Hogatzakaket, three hundred and
twenty-five miles from the mouth and one hundred and twenty-five miles
from the mission, at the camp of a prospector who had recently poled up
from the Yukon. We woke on board the launch the next morning to find ice
formed all around us and ice running in the river. The thermometer had
gone to zero in the night.

[Sidenote: THE RUNNING ICE]

A very brief attempt to make our way against the running ice showed the
danger of doing so, for the thin cakes had knife-edges and cut the
planking of the boat so that she began to leak. Then there came to me
with some bitterness that I had earnestly desired a thin steel
armour-plating at the water-line, but had allowed myself to be persuaded
out of it by her builders. So again my forethought had been of no
avail--though, of course, lightness of draught _was_ the first
consideration. We put back to the camp and proceeded to flatten out and
cut up all the empty cans and tinware we could find and nail it along
the water-line of the boat, but the prospector persuaded us to wait a
day or two. He had never seen a river close with the first little run of
ice. He looked for a soft spell and open water yet. It was foolish to
risk the boat against the ice. So we waited; and night after night the
thermometer fell a little lower and a little lower, until presently a
sheet of ice stretched across the whole river in the bend where we lay.
We were frozen in. The remote possibility we had feared and sought to
guard against had happened. Navigation had ceased on the Koyukuk at the
earliest date anybody remembered, the 23d of September. Three days more
had surely taken us to the mission where they had long expected us; now
we should have to make our way on foot, without dogs, on the dangerous
"first ice," as it is called, taking all sorts of chances, pulling a
Yukon sled, with tent and stove, grub and bedding, "by the back of the
face."

But first there was the launch to pull out and make snug for the winter
and safe against the spring break-up. A convenient little creek mouth
with easy grade offered, which was one of the reasons I had not pushed
on the few more miles we could have