CATARACTS OF THE ORINOCO. "From the rock of Manima a wonderful prospect is enjoyed. A foaming surface of four miles in length presents itself at once to the eye: iron-black masses of rock resembling ruins and battlemented towers rise frowning from the waters. Rocks and islands are adorned with the luxuriant vegetation of the tropical forest; a perpetual mist hovers over the waters, and the summits of the lofty palms pierce through the cloud of spray and vapour. When the rays of the glowing evening sun are refracted in these humid exhalations, a magic optical effect begins. Coloured bows shine, vanish, and reappear; and the ethereal image is swayed to and fro by the breath of the sportive breeze. During the long rainy season the streaming waters bring down islands of vegetable mould, and thus the naked rocks are studded with bright flower-beds adorned with Melastomas and Droseras, and with small silver-leaved mimosas and ferns. These spots recall to the recollection of the European those blocks of granite decked with flowers which rise solitary amidst the glaciers of Savoy, and are called by the dwellers in the Alps 'Jardins,' or 'Courtils.' "In the blue distance the eye rests on the mountain chain of Cunavami, a long extended ridge which terminates abruptly in a truncated cone. We saw the latter (Calitamini is its Indian name) glowing at sunset as if in roseate flames. This appearance returns daily: no one has ever been near the mountain to detect the precise cause of this brightness, which may perhaps proceed from a reflecting surface produced by the decomposition of talc or mica slate. "When M. Bonpland and I returned from the banks of the Rio Negro, we ventured to pass the latter or lower half of the Raudal of Atures with the loaded canoe, often leaving it for the rocky dikes which connect one island with another. Sometimes the waters rush over these dikes, and sometimes they fall with a hollow thundering sound into cavities, and flowing for a time through subterranean channels, leave large pieces of the bed of the river dry. Here the golden Pipra rupicola makes its nest; it is one of the most beautiful of tropical birds, with a double moveable crest of feathers, and is as pugnacious as the East Indian domestic cock. "In the Raudal of Canucari the rocky dike or weir consists of piled-up granite spheres. We crept into the interior of a grotto, the damp walls of which were covered with confervae and shining Bysus, and where the river rushed high above our heads with deafening noise. "We had accidentally more time than we desired for the enjoyment of this grand scene of nature. The Indians had left us in the middle of the cataract, proposing to take the canoe round a long narrow island, below which we were to reembark. We waited an hour and a-half under a heavy tempestuous rain; night was coming on, and we sought in vain for shelter between the masses of granite. The little monkeys, which we had carried with us for months in wicker cages, by their mournful cries attracted crocodiles, whose size and leaden-grey colour shewed their great age. I should not here notice an occurrence so usual in the Orinoco, if the Indians had not assured us that no crocodiles were ever seen in the cataracts; and in dependence on this assurance we had even ventured repeatedly to bathe in this part of the river. Meanwhile our anxiety lest we might be forced to pass the long tropical night in the middle of the Raudal, wet through and deafened by the thundering noise of the falling waters, increased every moment; until at last the Indians reappeared with our canoe. From the low state of the waters, they had found the steps by which they had intended to let themselves down inaccessible, and had been forced to seek among the labyrinth of channels for a more practicable passage."-- Humboldt's Aspects of Nature.