"You're fagged!" Rex exclaimed, noticing his plight. "Better rest here a minute!"
Lessari's answer was a vicious pull on the sleigh rope that nearly took Britton off his feet. They moved on because the Corsican would accept no delay, and Rex saw that the other's motive power was a sort of delirium which instilled unlimited feverish energy.
The pair of toilers emerged at last from the black rift and climbed an ice-capped ridge which fell like a sloping watershed in a southward direction. Around them the five beaver-house mountains rose strangely dome-like, the great river apparently losing itself in the bowels of the thousand ice chasms which furrowed the base of the valley-beds.
"This is the Klondike's source," Rex murmured as he contemplated the scene, "and it looks cold enough to kill you."
"Yes," sighed Lessari, "you have it right. But the gold–the gold is warm. Here I feel it!" He put his hand to his breast, and smiled contentedly.
"It's all that's keeping you warm," Rex gruffly commented. The observation quickly altered Lessari's expression, and he glared with a wild impenetrable look as they proceeded to skirt the fringing line of gravelled granite which was the shore of the now glacier-like stream.
Here the detached ice lay scattered about in huge blocks, an impediment to their feet, where it had glided with the shining rubble from the farther plateaus. In the shallow cup that the five hills formed, they met with a long, treacherous crevasse whose yawning depth of three hundred feet effectually cut off any further progress in a direct line. The great abyss seemed to possess a fascination for Lessari, and he trod dangerously near the edge to peer over.
"Don't do that!" Britton sharply cautioned, pulling him back. "A slip of your moccasin would put you at the bottom. We'll have to leave the sled here and see if there is any way round!"
The immense crevasse dipped from an overhanging glacier on one of the five mountains and slanted across the granite ridge they had been skirting. The two men left the Yukon sleigh standing, blocked, above the deep split and followed along the edge, searching for a place to cross. The slant of the ravine became more, acute, and, where the sides were jagged and shelved, they clambered down lower and lower till the whole formation suddenly broke upon a vast cavern that nosed into the river-bed and opened on the other side where the way was passable though extremely hard.
"It's rough going, but we must get across," Rex said, turning round to Lessari.