as about to be destroyed. They quickly saw, however,
that the body of the moss was not burning; it was too thoroughly
permeated with ice for that, and that the fire was only flashing over
its dry under surface.

[Illustration: FOR A SINGLE MINUTE THEY GAZED IN BREATHLESS AWE.]

As they watched these fitful flames running along the roof and
illuminating remote recesses of the cavern, all three suddenly uttered
cries of amazement, and each called the attention of the others to the
most wonderful sight he had ever seen. Brilliantly lighted and
distinctly outlined against the dark background of a clay bank, that
held it intact, was a gigantic skeleton complete in every detail, even
to a huge tusk that curved outward from a massive skull. For a single
minute they gazed in breathless awe. Then the illuminating flame died
out, and like a dissolving picture the vast outline slowly faded from
view and was lost in the blackness.

"Was that one of 'em?" gasped Jalap Coombs.

"I expect it was," answered Phil.

"Waal, then, old Kite didn't make no mistake when he said a tagger
warn't a sarcumstance."

"It must have been all of twenty feet high," remarked Serge,
reflectively.

For more than an hour they talked of the wonderful sight, and Phil told
what he could remember of the gigantic hairy mammoth discovered frozen
in a Siberian glacier, and so perfectly preserved that sledge-dogs were
fed for weeks on its flesh.

As they talked their fire burned low, and the outside cold creeping
stealthily into camp turned their thoughts to fur-lined sleeping-bags.
So they slept, and dreamed of prehistoric monsters; while Musky, Luvtuk,
Amook, and their comrades restlessly sniffed and gnawed at the ancient
bones of this strange encampment, and wondered at finding them so void
of flavor.

Glad as our sledge travellers would have been to linger for days and
fully explore the mysteries of that great moss-hidden cavern, they dared
not take the necessary time. It was already two weeks since they had
left the mining-camp, winter was waning, and they must leave the river
ere spring destroyed its icy highway. So they were off again with the
first gray light of morning, and two days later found them at the mouth
of the Pelly River, the upper Yukon's largest tributary, and two hundred
and fifteen miles from Forty Mile.

One evening they spent in the snug quarters of Harper, the Pelly River
trader, who was the last white man they could hope to