Plutonian views, is the most plausible, and indeed is that explanation which may be viewed as most in accordance with prevailing geological hypotheses.

Vegetables incrusted with Calcareous Sand confounded with Coral, and adduced as a Proof of the very recent Emergence, from the Ocean, of the Lands supporting them.-Somewhat to the eastward of Simon's Town is a large bank, one hundred feet above the level of the sea, formed by an accumulation of sand and shells, brought there by the action of the wind. On this bank Abel observed a number of cylindrical calcareous bodies scattered about, which at first appeared like bleached bones. On a closer examination many of them are found to be branched, and others are discovered rising through the soil, and ramifying from a stem beneath, thicker than themselves. They are incrustations of sand and calcareous matter on vegetables. Similar bodies have been found by Vancouver, Flinders, and Perron, on the shores of New Holland, at considerable elevations. The first-mentioned traveller considered them all as coral, and as proofs of the land having been lately withdrawn from the dominion of the waters. The last has described two kinds of substances; the one he considers as coral, the other as incrustations on vegetables. Captain Flinders, at page 48, vol. i. of his Voyage Round the World, says, "The appearance of this country along the coast resembles, in most respects, that of Africa about the Cape of Good Hope. The surface seemed to be chiefly composed of sand, mixed with decayed vegetables, varying exceedingly in point of richness, and, although bearing a great similarity, yet indicating a soil superior in quality to that in the im

mediate neighbourhood of Cape Town. The principal component part of this country appeared to be coral; and it would seem that its elevation above the ocean is of modern date, not only from the shores, and the bank which extends along the coast being, generally speaking, composed of coral, as was evident by our lead never descending to the bottom without bringing up coral on its return, but by coral being found on the highest hills we ascended, particularly on the summit of Bald Head, which is sufficiently above the level of the sea to be seen 12 or 14 leagues distant. Here the coral was entirely in its original state, particularly in one level spot, comprehending about eight acres, which produced not the least herbage on the white sand that occupied this space, through which the branches of coral protruded, and were found standing exactly like those seen in the beds of coral beneath the surface of the sea, with ramifications of different sizes, some not half an inch, others four or five inches in circumference. In these fields of coral, (if the term field be allowable,) of which there were several, seashells were in great abundance,—some nearly in a perfect state, still adhering to the coral, others in different stages of decay. The coral was friable in various degrees; the extremities of the branches, some of which were nearly four feet above the sand, were easily reduced to powder, whilst those close to, or under the surface, required some small force to break them from the rocky foundation from whence they appeared to spring. I have seen coral in many places at a considerable distance from the sea; but in no other instance have I seen it so elevated and

in such a state of perfection." Captain Flinders, at page 63, vol. i. of his Voyage to Terra Australis, has the following remarks on the same appearance: -"Captain Vancouver mentions having found, upon the top of Bald Head, branches of coral protruding through the sand, exactly like those seen in the coral beds beneath the surface of the sea,-a circumstance which should seem to bespeak this country to have emerged from the ocean at no very distant period of time. This curious fact I was desirous to verify, and his description was proved to be correct. I found also two broken columns of stone, three or four feet high, formed like stumps of trees, and of a thickness superior to the body of a man; but whether they were of coral, or of wood now petrified, or whether they might not have been calcareous rocks, worn into that particular form by the weather, I cannot determine. Their elevation above the present level of the sea could not have been less than 400 feet."

Perron says, " On breaking the branches where the incrustation is recent, we observe the woody texture contained in a solid case, and without any remarkable alteration; but, in proportion as the calcareous envelope increases, the wood becomes disorganized, and changes insensibly into a dry and black powder." From this state he supposes the centre gradually to increase in solidity till the whole mass becomes a mere sandstone, and nothing but an arborescent form indicates the ancient state of vegetation.

The incrustations near Simon's Town are of a similar nature to those found in New Holland, because, says Dr Abel, the descriptions of authors cor

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respond with the appearances I have witnessed, and because I have compared a specimen brought from Bald Head in New Holland, by Mr Brown, with those I obtained at the Cape, and can trace no essential difference, either in the external characters or chemical composition. It follows from this statement, that Flinders and Vancouver have confounded vegetable incrustations with true corals; and hence the reasoning on their supposed submarine origin, and modern rising of the Bald Head, &c. above the level of the ocean, is incorrect.

Geology of the North and South, and East and West Ranges of Mountains.-The 'ranges of mountains which run northward from the Cape Penin, sula to Orange or Gariep River, in the points where examined, exhibited granite and slate, with vast deposites of sandstone or quartz rock with numerous table-shaped summits,-thus showing a similarity of composition in these mountains to those of the Cape Peninsula.

The three great ranges of mountains that run from east to west, according to the reports of travellers, are of the same general nature, and eminently characterized by the vast abundance of sandstone reposing in horizontal strata upon the granite and slate, forming the middle, and very often the higher parts of the chains.

Geology of the Table-Land-From the third range onwards to lat. 30° S., the prevailing rock in the plains and hills is sandstone. At Dwaal River, the frontier of the colony, there are rocks of augite-greenstone and basalt, probably in veins. traversing the sandstone. Rocks of the same description, disposed in beautiful globular concre

tions, (not boulders, as stated by Burchell,) occur near to Kaabes Kraal, 29° S. lat., probably in veins traversing the horizontal sandstone of that district. The Karreebergen, or Dry Mountains, beyond the limits of the colony, form a range from five to ten miles broad, and range through the country to an unknown distance, from N. E. to S. W. These mountains are principally composed of sandstone, in horizontal strata, and everywhere exhibit beautiful table-shaped summits. According to Burchell, "The sandstone rock continues onward to lat. 30° S., to near Modde or Mud-Gap, where true quartz strata and vesicular trap-rocks make their appearance. In lat. 29° 15' 32" S., mountains, called the Asbestos Mountains, of clay-slate, disposed in horizontal strata, occur; there layers of asbestos occur in the slate. This asbestos is blue and yellow, and the fibres sometimes nearly three inches in length." In the same mountain, according to Burchell, green opal and pitchstone also occur. A range of black craggy mountains extends from the Kloof, in the Asbestos Mountains; the rocks are very probably trap. Further to the north, at Klaarwater, are vast beds of horizontally-stratified limestone, without organic remains.

Account of the Sibilo of the Africans.-At Sensavan, or Blenk-Klip, nearly in S. lat. 28°, there is a ridge of quartz rock impregnated with micaceous iron ore, which, in many places, is collected into nests of considerable magnitude. This ore of iron is known throughout Southern Africa by the name Sibilo. Hither all the surrounding nations repair for a supply of that ornamental, and, in their eyes, valuable substance. It forms, in some degree, an