After a few days we concluded that a visit to the top of the range, which at this point attains an altitude of over ten thousand feet, was necessary. We secured a pack-train of mules from Acherál, and one morning at one o’clock started up the steep slope. A full moon showered a flood of light upon the earth, but the overhanging branches formed a thick canopy over the trail, impermeable to the silvery radiance save when an occasional breeze stirred the leafy arch, thus permitting fitful shafts of light to pierce the darkness of the tunnel, and to fall in quavering, dancing blotches on the ground. We could almost feel the impenetrable blackness which closed in from all sides like water in a deep, dark pool. The light touch of a streamer dangling from the moss-festooned branches overhead, or the velvety swish of fern leaves protruding beyond the protecting walls of tree-trunks, made it seem as if the forest were peopled with hovering, invisible forms. No sound disturbed the brooding silence of the night except the dull hoof-beats of the mules as, guided by some mysterious instinct, they cautiously picked their way through the muddy and rock-strewn lane. Hour after hour we followed blindly in the wake of the bell-mule, winding back and forth along the mountainside, but mounting ever upward. The latter part of the way seemed to lie near the course of a small mountain torrent, for we were almost constantly within hearing distance of rushing water. Finally, we emerged from the forest, and, just as day was breaking, reached a brush-covered strip of country, the elevation of which is five thousand feet. This continued to the top of the ridge, two thousand feet above. Then there was a depression of considerable extent, filled with rank, low vegetation and infested with swarms of bloodthirsty flies which render it uninhabitable. After ascending another ridge, the trail led gently downward into a level valley a dozen miles long and from one to two miles wide. Herds of cattle were grazing on the abundant grass; a few small areas had been enclosed within stone walls and planted in maize; and at the far end, half concealed by willows and fruit-trees, lay a village of whitewashed houses. At half past four in the afternoon we reached the settlement, called Tafí del Valle, and soon after were comfortably ensconced in a hut hospitably provided by one of the inhabitants. After the fifteen and a half hours’ uninterrupted ride over a difficult trail we were ready for a journey into a still more remote region, and the sun was shining brightly the following morning when we again returned to the stern realities of this world.