build a fire and dry his garments.

Nothing daunted him. It was because nothing daunted him that he
had been chosen for government courier. He took all manner of
risks, resolutely thrusting his little weazened face into the
frost and struggling on from dim dawn to dark. He skirted the
frowning shores on rim ice that bent and crackled under foot and
upon which they dared not halt. Once, the sled broke through,
with Dave and Buck, and they were half-frozen and all but drowned
by the time they were dragged out. The usual fire was necessary
to save them. They were coated solidly with ice, and the two men
kept them on the run around the fire, sweating and thawing, so
close that they were singed by the flames.

At another time Spitz went through, dragging the whole team after
him up to Buck, who strained backward with all his strength, his
fore paws on the slippery edge and the ice quivering and snapping
all around. But behind him was Dave, likewise straining backward,
and behind the sled was Francois, pulling till his tendons
cracked.

Again, the rim ice broke away before and behind, and there was no
escape except up the cliff. Perrault scaled it by a miracle,
while Francois prayed for just that miracle; and with every thong
and sled lashing and the last bit of harness rove into a long
rope, the dogs were hoisted, one by one, to the cliff crest.
Francois came up last, after the sled and load. Then came the
search for a place to descend, which descent was ultimately made
by the aid of the rope, and night found them back on the river
with a quarter of a mile to the day's credit.