At once, as if relieved, he sprang up, and crying, “Come on, follow me!” began to make his way up the bed of the brook. It was one of the wildest walks that I have ever taken. He turned aside for no obstacles; swamps, masses of interlacing alders, close-woven thickets of stiff young spruces, chevaux-de-frise of dead trees where wind-falls had mowed down the forest, walls of lichen-crusted rock, landslides where heaps of broken stone were tumbled in ruinous confusion--through everything he pushed forward. I could see, here and there, the track of his former journeys: broken branches of witch-hazel and moose-wood, ferns trampled down, a faint trail across some deeper bed of moss. At mid-day we rested for a half-hour to eat lunch. But Keene would eat nothing, except a little pellet of some dark green substance that he took from a flat silver box in his pocket. He swallowed it hastily, and stooping his face to the spring by which he had halted, drank long and eagerly. “An Indian trick,” said he, shaking the drops of water from his face. “On a walk, food is a hindrance, a delay. But this tiny taste of bitter gum is a tonic; it spurs the courage and doubles the strength--if you are used to it. Otherwise I should not recommend you to try it. Faugh! the flavour is vile.” He rinsed his mouth again with water, and stood up, calling me to come on. The way, now tangled among the nameless peaks and ranges, bore steadily southward, rising all the time, in spite of many brief downward curves where a steep gorge must be crossed. Presently we came into a hard-wood forest, open and easy to travel. Breasting a long slope, we reached the summit of a broad, smoothly rounding ridge covered with a dense growth of stunted spruce. The trees rose above our heads, about twice the height of a man, and so thick that we could not see beyond them. But, from glimpses here and there, and from the purity and lightness of the air, I judged that we were on far higher ground than any we had yet traversed, the central comb, perhaps, of the mountain-system. A few yards ahead of us, through the crowded trunks of the dwarf forest, I saw a gray mass, like the wall of a fortress, across our path. It was a vast rock, rising from the crest of the ridge, lifting its top above the sea of foliage. At its base there were heaps of shattered stones, and deep crevices almost like caves. One side of the rock was broken by a slanting gully.