So they chopped vigorously at the ice-bound drift-log that had induced them to halt at that point, and half an hour later the gloom of their cavern was dispelled by a roaring, snapping, up-to-date blaze. By its cheerful light they examined with intense interest the great fossil bones that lay scattered about them. "I should think a whole herd of mammoths must have perished at once," said Phil. "Probably they were being hunted by some antediluvian Siwash and got bogged in a quicksand. How I wish we could see a whole one! But, great Scott! Now we have gone and done it!" Phil's final exclamation was caused by a crackling sound overhead. The sloping moss roof had caught fire from the leaping blaze, and for a moment the dismayed spectators of this catastrophe imagined that their snug camping-place was 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.