On every side of them rose giant trees of hoary age, their trunks seemingly supporting the verdant roof above-head. At times, so dense were the leaves that sky and sun and kindly light were shut out entirely, and they moved through a translucent twilight of tremulous green. From trunks and boughs depended lianas like ropes binding the forest giants together, or, dropping to the ground, formed a ladder up which climbed the most exquisite flowers. Splendid tree-ferns drooped their gigantic fronds on high, springing thickly from tall pillars, rough, brown, and hairy. Below, the ground was thick with brilliant blossoms, which seized every chance offered by rock, liana, and trunk to climb upward to that light excluded by the sea of foliage overhead. At every step the forest changed its appearance, as though it were an enchanted wood. Here, all was savagery and gloom; step forward, and lo! a wide and sunny glade. One moment, and they were surrounded by moss-covered rocks; the next, and a noble avenue of palms opened a vista before them. Pools of water sparkled here and there; babbling brooks winding capriciously in and out in wayward circles; at times, the sudden gleam of a waterfall, threading downwards in white streaks from a giant rock; and again, the miasma of a swamp, black and evil-looking, in whose waters rolled the trunks of fallen trees. Everywhere flowers bursting into bloom; everywhere new leaves swelling into being; everywhere the exuberant life of a tropic climate. The atmosphere was warm and damp, a clammy air permeated the woods, and the whole place was one vast hothouse, where fecundation went on unceasingly. Throughout, a rich perfume pervaded the air, heavy, sickly, and languorous. Fortunately, Jack's sight had been rendered keen by his profession, else it would have been difficult to have discerned the sign, on trunk of tree, or mossy rock. Scarlet is a noticeable colour, and had the opal sign been the only red hue in the forest, there would have been no difficulty in the matter. But everywhere scarlet flowers made fire of the intense emerald of foliage and grass. Dazzling masses of crimson verbena glared fiercely in the dim gloom, vermilion blossoms burned like lamps in the dense brushwood, wreaths of ruddy leaves made streaks like veins overhead, and the ground blazed with the pinks and carmines and purples of an infinite variety of blossoms. It was difficult to pick out the red-opal sign amid this constant repetition of the same tints; but Jack, by careful observation, managed to do so, being guided at times by a well-defined path. Indeed, often he was tempted to ignore the sign, and go only by the path; but, as numerous branches led off from the omphalos of the great road, he was afraid of going astray, so kept his reckoning by the opal alone.