All the way, too, went the trail of the wolverine, and, judging from the tracks, the boys guessed that the animal had been traveling fast. This looked ominous, for the wolverine is not, as a rule, an energetic animal, and proved at least to Tom’s mind that the robber must be traveling very quickly.
He pointed this out to Jack, who agreed with him. But neither of the boys said a word about turning back. They were far too nervy for that, and, having started out, such an idea as quitting did not once enter their heads. All that afternoon they kept grimly on.
At about three o’clock, or shortly thereafter, the sun grew dim and low. Half an hour later only a pale twilight lingered about them, for at that time of year in the northern wilds the evening sets in early.
Above their heads, from the darkening canopy of the sky, the stars, a million pin points of light, began to shine. The snow turned a dull, steely blue as the light shut in. A slight breeze stirred in the hemlocks and spruces. It began to grow noticeably colder, too.
But as the daylight died another light, a wonderful mystic glory of radiance, began to glow in the northern sky. Against its wavering, shimmering, unearthly splendor every twig on every tree stood out as though carved in blackest ebony. The brush was shrouded in deepest sable, and the shadows lay upon the snow as black as a crow’s wing.
Everywhere was a deep, breathless hush, except where the light wind caused a huddled mass of snow on an interlaced branch to slip ground-ward. The great solitudes appeared to be composing themselves for sleep. On the hard, frozen surface the boys’ snowshoes creaked almost metallically as they pressed on, following in the dimming light the two parallel lines that had begun to burn themselves into their brains.
They knew when they set out that it was going to prove a stern chase; now they saw that unquestionably it was likewise to be a long one. How long they could not guess. They passed a small stream. In the silence they could hear the ice “crack-cracking!” with that startling sound that is one of the most mystic of the voices of the woods. It grew bitterly cold. Tom began to look anxiously about him. They must find a lodging for the night. The question of sleeping in the open did not bother him. Timber was plenty, and they could make an evergreen shelter and soon have a roaring fire to warm their blood. He was merely prospecting for a place that looked a likely one.
And then, suddenly, something happened that sent an involuntary chill running up and down the spines of both boys.
From the westward, through the long, melancholy aisles of straight-trunked trees, the sound had come. Out of the silence it was borne with a chilling forboding to them. It was a long-flung, indescribably forlorn sound, and seemed to fill the silences, coming from no definite spot after an instant’s listening.
It deepened and swelled, died away and rose like the sound of distant church bells. Then, while they stood listening, involuntarily brought to a swift, startled halt, it died out uncannily, sinkingly, and the silence shut down again.