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Show 4 ST. JAGO-CAPE DE VEUD ISLANDS. Jan. 1832. and could not be approached. They avoided us, ~ke pa~trido- es on a rainy day in September, running With theu heads cocked up ; and if pursued, they readily took to the wing. The scenery of St. Domingo possesses a beauty totally unexpected, from the prevalent gloomy character of the rest of the island. The village is situated at the bottom of a valley, bounded by lofty and jagged walls of stratifie.d lava. The black rocks afford a most striking contrast with the bright green vegetation_, which follows the banks of a little stream of clear water. It happened to be a grand feast-day, and the village was full of people. On our return we overtook a party of about twenty young black girls, m:esse.d in most excellent taste ; their black skins and snow-white lmen being set off by their coloured turbans and large shawls. As soon as we approached near, they suddenly all turned round, and coverino- the path with their shawls, sung with great 0 . energy a wild song, beating time with their hands upon therr legs. We threw them some vintems, which were received with screams of laughter, and we left them redoubling the noise of their song. It has already been remarked, that the atmosphere is generally very hazy; this appears chiefly due to an impalpable dust, which is constantly falling, even on vessels far out at sea. The dust is of a brown colour, and under the blowpipe easily fuses into a black enamel. It is produced, as I believe, from the wear and tear of volcanic rocks, and must come from the coast of Africa. One morning the view was singularly clear ; the distant mountains being projected with the sharpest outline, on a heavy bank of dark blue clouds. Judging from the appearance, and from similar cases in England, I supposed that the air was saturated with moisture. The fact, however, turned out quite the contrary. The hygrometer gave a difference of 29.6 degrees, between the temperature of the air, and the point at which dew was precipitated. This difference was nearly double that which I had observed on the previous mornings. Jan. 1832. GEOLOGY. 5 This unusual degree of atmospheric dryness was accompanied by continual flashes of lightning. Is it not an uncommon case, thus to find a remarkable degree of aerial transparency with such a state of weather ? The geology of this island is the most interesting part of its natural history. On entering the harbour, a perfectly horizontal white band, in the face of the sea cliff, may be seen running for some miles along the coast, and at the height of about forty-five feet above the water. Upon examination, this white stratum is found to consist of calcareous matter . ' w1th numerous shells embedded, such as now exist on the neighbouring coast. It rests on ancient volcanic rocks, and has been covered by a stream of basalt, which must have entered the sea, when the white shelly bed was lying at the bottom. It is interesting to trace the changes, produced by the heat of the overlying lava, on the friable mass. For a thickness of several inches it is converted, in some parts, into a firm stone, as hard as the best freestone ; and the earthy matter, originally mingled with the calcareous, has been separated into little spots, thus leaving the limestone white and pure. In other parts a highly crystalline marble has been formed, and so perfect are the crystals of carbonate of lime, that they can easily be measured by the reflecting goniometer. The change is even more extraordinary, where the lime has been caught up by the scoriaceous fragments of the lower surface of the stream ; for it is there converted into groups of beautifulJy radiated fibres resembling arragonite. The beds of lava rise in successive gently-sloping plains, towards the interior, whence the deluges of melted stone originally proceeded. Wi~hin historical times, no signs of volcanic activity have, I beheve, been manifested in any part of St. J ago. This state of quiescence is, probably, owing to the neighbouring island of Fogo being frequently in eruption. Even the form of a crater can but rarely be discovered on the summits of any of the red cindery hills ; yet the more recent streams can be distinguished on the coast, forminrr a.line of cliffs of less heio-ht b u 5 ' ut stretching out in ad vance of those belonging to an older |