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extremities of the ranges. The most southern rivers, such as the Johore, Sakadai, &c. which flow southward, would also bend to the east and west, where the last system of the continent terminates and that of Singapore begins, did they not meet with a depression so low as to be accessible by the sea. Singapore is merely separated from the mainland by this depression, which forms a narrow tortuous river-like arm of the sea, and is in fact sunk into the continent and embraced by it on three sides, so that its southern shore seems to be the proper continuation of the southern coast of the Peninsula. Its geographical connection with it is therefore complete. When we cross the strait no difference in the topography is observable. And the low hills which give the surface an undulating appearance like that of Singapore, probably resemble those of the latter in their internal structure as much as they do in the superjacent soils and in the stunted jungle. The interior of the Peninsula is almost wholly unexplored. In coasting along its western shore from Pinang to Cape Rachado a high chain or rather series of ranges of mountains is observed inland nearly the whole way, which from their generally sharp-peaked summits, the nature of the detritus brought down from them by the rivers, and the evidence afforded by the few points where they have been reached, we are justified in believing to consist in great measure of plutonic rocks. In front of this range we observe a broad tract of country often appearing to be perfectly flat and very little above the sea level for miles together, but from which sometimes low hills rise like Islands out of the sea. These hills are frequently quite solitary and at a great distance from the central mountains, or near the coast. Further inland they seem to be generally in groups, and towards the mountains the country at some places appears hilly and undulating. At Malacca these low hills are so much grouped as to resemble some parts of Singapore, and they are covered by gravel and fragments precisely similar to those found on some of the Singapore hills. In some of the hills opposite Pinang I observed similar fragments. In both cases the soil had a deep red ferruginous aspect.* That most of the hills scattered along the western plains of the Peninsula were Islands in the sea at no remote date, there can be no doubt. The plains from which they spring are flat, generally only a few feet above the sea level, alluvial and at some places abounding in marine shells of the same species that at present inhabit the straits. The rivers of the Peninsula, although generally small, are exceedingly numerous, and bring down large quantities of sediment. In March last, off the mouth of the Salangore river, the steamer in which I was, passed through a broad tract discoloured by the sediment. Extensive mud banks have been formed in the straits and are constantly increasing. For evidence on this subject I must refer to a separate paper containing some remarks on the Straits of Malacca and the alluvial tracts along its sides. It is not therefore unreasonable to conclude that the whole chain of these hills from Pinang to Singapore has a strict geological connection. At Malacca hot springs exist, and the hills nearest to them are of the mature before mentioned. We naturally resort to the mountain chain of the interior for the seat of that central volcanic force of which the manifestations on these outskirts are of so peculiar a character, so wide in their extent yet so devoid of intensity. But we find that there is no evidence whatever of any volcanoes ever having existed in this chain. If there ever were any their fires have long been quenched. If we now direct our attention to the southward of Singapore, we find that it is but one of an extensive archipelago of Islands, stretching to the south-east, and which after a slight interruption, is continued in Banca. That the geological chain continues to the latter Island is clear from the account which Dr. Horsfield gives of it. According to him the elevated parts of Banca consist principally of granite, but in the secondary elevations “red iron stone” is extensively distributed in single rocks, or in veins of many united together covering large tracts of country.* This circumstance and the general topography of the Island, as described by Dr. Horsfield, assimilate to Singapore. The paucity of tin ore in the latter arises from the want of granitic hills. Bukit Temah, the only hill yet explored in which sicnite abounds, contains tin, * See memoirs of Sir S. Rafiles, p. 150. Major Court, in his account of Banca notices the gravelly nature of the soil (Court's Palembang). Professor Jameson, in Murray's Encyclopædia of Geography, mentions the circumstance of the primitive mountains being immediately bounded by a formation of red iron stone doubtingly, and adds, “Crawford who makes this statement gives no description of the formation.” From Crawford's

* Cape Rachado is described by Crawford to consist of quartz rocks interspersed with frequent veins of clay iron ore.

meagre notice of Banca I presume he does not write from personal observation, and like Sir S. Raffles, he probably derived his information from Dr. Horsefield's manuscript.

and in fact derives its name from the circumstance, as it literally signifies “Tin Hill.” We thus find that what we may call the semi-volcanicband of the straits of Malacca may, to a certain extent, be disconnected from the Peninsula, and viewed as a chain of Islands extending probably foom Junk-ceylon to Banca, and including the existing Islands and numerous rocks and reefs in the straits of Malacca. It appears therefore, that its southern extremity is almost in contact with Sumatra,” and the question arises whether its volcanic connection be not with this great Island rather than the Peninsula. May it not be reasonably presumed that if the origin and partial elevation of the Sumatra chain was contemporaneous with that of the Peninsula, the line of greatest intensity of the subterranean forces, in whichever it was originally, was ultimately determined to the latter chain, and that at some now ancient era the former was left to comparative repose 1 The height of the plutonic mountains of the Peninsula is greatly inferior to that of the mountains of Sumatra. But all the elevated peaks of the latter appear to be volcanic, and perhaps the purely granitic ranges are not more elevated than those of the Peninsula. The elevation of the two plutonic ranges and the shallow bed of the strait between them may have been contemporaneous and antecedent to the period when volcanoes burst out along the Sumatra chain. These volcanoes, from their number and power would arrest the rise of the region, or cause any subsequent elevatory movement to be rare and of small amount. Until the interior of the Peninsula is explored these inquiries to a large extent must be merely speculative. But it is certain that the Sumatra chain has in recent eras been the seat of great volcanic energy, and that it is still subject to convulsive movements, the tremors or undulations of which are transmitted as far as what I have termed the semi-volcanic band of the straits on the one side, and which are felt much more severely in the less distant chain of Islands on the west coast of Sumatra. Marsden states that a number of volcanoes existi and describes one which opened in the side of a mountain about 20 miles inland of Bencoolen, and which during his residence at that Factory scarcely ever failed to emit smoke. To the S. E. the three volcanic peaks of Gunong

• It will appear however in the paper formerly referred to that this approximation is due to modern external, not to ancient internal forces. # I listory of Sumatra, p. 24.

Dempo, Lumut and Berapi, rise to the height of 12,000 feet. Gunong Dempo was ascended by Mr. Church, the present resident councillor at Singapore, with the late Mr. Presgrave in 1818. An interesting account of the ascent is inserted in Rafiles' Memoirs, (p. 323.) Mr. Presgrave states that he had frequently seen smoke issuing from? the mountain, and the natives informed him that within their memory it had emitted flames attended with a loud moise. In the upper region of the mountain the party found the trees dead and externally burned quite black. Further north is the great central volcanic region, partially at least included in the ancient kingdom of Menang Kabu. This is described by Raffles, (Memoirs, p. 347) as being exclusively volcanic. The rocks are mostly basaltic. Two lofty volcanic mountains rise near the large lake of Sincara. From one of these, Gunong Berapi (fiery mountain) which is above 13,000 feet high, smoke issued. Hot springs also exist here. To the east of the lake at the rocks consisted of felspar, granite, quartz, &c mixed with a great variety of volcanic productions in the greatest confusion. Iron ore of various kinds lay in the path of the travellers. To the west of the lake were found granite, marble, great varieties of limstones, masses of calcareous spar and many other substances. On the N. E. of the lake near Pageruyang numerous stumps and trunks of trees in a state of petrifaction protruded from the ground. The limits of the region on the north and south are not ascertained. About 60 miles south of Mt. Talong another Gunong Berapi occurs. Near Mt. Ophir a volcanic mountain is marked in Marsden's map, and Mt. Ophir itself is probably an extinct volcano. Further morth still lies another of the ascertained volcanoes Mt. Batagapit. Mr. J. Anderson, who visited the east coast in 1823, mentions* a native tradition of an engagement having taken place between two of the mountains in the interior of Delli (Sebaya and Senaban) when part of them fell into the valley. From these mountains sulphur is procured, which if it does not prove that they are formed of volcanic materials as Mr. Anderson conceives, at least leads to the inference that they have been the seat of volcanic action. At Acheen abundant supplies of sulphur for internal consumption and exportation are obtained from a volcanic mountain in the neighbourhood.t Lastly, one of the western chain of Islands, Si Beero, according

* Mission to the E. coast of Sumatra, p. 199. # Marsden, p. 313.

to Marsden, possesses a volcano. Earthquakes are of frequent occurrence. Marsden notices one of unusual severity, which occurred in 1770.* Sir T. Raffles mentions that on the east coast they are said to happen every-5 or 6 years.t. The Malays on the east coast represented to Mr. Anderson that slight shocks were occasionally felt; and the same information was received by Lieut. Craoke at Jambi. § In the interesting memoir on this state by that officer appended to Mr. Anderson's work, it is likewise mentioned that a violent earthquake was stated to have been experienced about 20 years or more previous to his visit in 1820, and to have been preceded by a period of great heat and drought, which ruined the crops and occasioned a distressing scarcity of food. It is not improbable that this earthquake was simultaneous with one which happened in 1797, of which the effects on the opposite coast is mentioned by Raffles. “It is stated that the vibratory shocks continued for 3 minutes, and recurred at intervals during the space of 3 hours till the shock completely ceased. At Padang, the houses of the inhabitants were almost entirely destroyed and the public works much damaged. A vessel lying at anchor was thrown by the sudden rise of the tide upwards of three miles on shore. The number of lives lost there amounted to above 300 : of these some were crushed under the ruins of falling houses, some were literally entombed by the

* “The most severe that I have known, was chiefly experienced in the district of Manna, in the year 1770. A village was destroyed by the houses falling down and taking fire, and several lives were lost. The ground was in one place rent a quarter of a mile, the width of two fathoms, and depth of four or five. A bituminous matter is described to have swelled over the sides of the cavity, and the earth, for a long time after the shocks, was observed to contract and dilate alternately. Many parts of the hills far inland could be distinguished to have given way, and a consequence of this was, that during three weeks, Manna river was so much impregnated with particles of clay, that the natives could not bathe in it. At this time was formed, near to the mouth of Padang Goochie, a neighbouring river, south of the former, a large plain, seven miles long and half a mile broad; where there had been before only a narrow beach. The quantity of earth brought down on this occasion was so considerable, that the hill upon which the English resident's house stands, appears, from indubitable marks, less elevated by fifteen feet than it was before the event.” Id, p. 25.

t Memoirs, p. 295.

t Anderson, ut supra, p. 199.

§ Id. p. 402.

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