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heavy rains, day and night, without suffering in health. I have no reason, therefore, to consider it as unhealthy as it is reported to be.
The population appears small and inadequate for the purpose of public works; but I have been assured laborers can be procured from some parts of the interior. I am, however, of opinion that, if any important works are undertaken, an additional and more effective set of hands would be indispensable.
5. Geology and Mineralogy of the Malay Peninsula, (Mining Journal, April 22, 1848.)-The litile that is known of the physical geography and geology of the peninsula of India, renders the most general information of the greatest interest. The knowledge of this immense tract, extending over 83,000 geographical square miles-the interior of which is almost untrodden ground, at least to European footmust depend on future exploration ; but any information, even of its coast line and adjoining islands, is of importance, and tends to incite to further observation. Its western coast is remarkable for the great number of islets which skirt it ; a broad and almost uninterrupted belt extends along all the western side of the isthmus. Some of these are remarkably bold and imposing—such as the Johore Archipelago, and the Redang Islands. The concave southern half embraces the Island of Singapore ; and an archipelago of several hundred miles, stretching southeast by south, marks that the peninsular zone has not yet wholly sunk beneath the sea, and attests how nearly a junction with Sumatra has been accomplished. Most of the Islands are bold; and one of them (St. Matthew) rises to the height of 3000 ft. The isthmus itself is occupied by numerous high hill ranges, which have the same general southerly direction. Along the sea borders, considerable tracts of flat alluvial land occur, the best known of which is the large plain of Tenesarim. From Junk-Ceylon to the Langkawi group, the coasts of the main land and Islands exposed to the full force of the Bengal Sea, are broken, and . frequently rocky and precipitous. The high and perpendicular limestone rocks, with their deep excavations, pillared with colossal stalactites and with their summits crowned with dense forests, present the most magnificent scenery. The Island of Penang is a bold mountain mass, rising in some of its northerly summits to the height of nearly 3000 ft., and contrasting nobly with the broad and beautiful plain which lies opposite to it, on the main land. Geologically, the peninsula may be considered, when divested of its alluvial fringes, as one continuous belt of mountains and hills, separated from the Hindu-Chinese region in lat. 13° 30' north. We find that the broad tract, stretching eastward towards Siam, Cambodia, Cochin-China, with which the peninsular zone is amalgamated, is not a uniform elevated continental mass in which the peninsula merges, as the straits of Malacca lapse in the Sea of Bengal. The zone of elevation continues uninterruptedly--the western border being a broad sheet of alluvium ; beyond this alluvium, another elevated zone occurs, succeeded by a second tract of alluvium, which again is bounded by a third elevated belt. How far to the north these great alluvial plains extend, and how much the northern limit of the Malay Peninsula has been pushed south by the gradual filling up of the northern part of the Gulf of Siam, we have no authentic knowledge. The rocks are principally plutonic ; but considerable masses of sedimentary rocks oc
Second SERIES, Vol. VI, No. 16.-July, 1848. 17
cur, consisting of limestones, sandstones, common clays, and shalcs. In the famous tin island (Banca) the prevailing stratified rocks are clays and sandstones. In many cases plutonic action has indurated the superincumbent strata, converting sandstones into compact siliceous rocks and clays, and conglomerates into schist and other hard crystalline forms. In Malacca are several thermal springs. This fact, combined with some proofs of recent upheaval, leads to the surmise that it still retains the character of a rising region-a surmise which its proximity to Sumatra countenances.
Metals.—The tendency to the production of metalliferous ores at and near the junction of plutonic and sedimentary rocks, which has been observed in many countries, might have led us to anticipate a large share of metallic riches for the peninsula. In reality, it probably abounds in some ores far beyond conception.
Iron ores are every where found, and in the south they exist in vast profusion. In some places the strata have been completely saturated with iron ; and here the bare surface of the ground, strewed with blackish scoriform gravel and blocks, presents a strange contrast to the exuberant vegetation of surrounding tracts, appearing as if it had been burned and blasted by subterranean fires. Much of the ordinary forms of ironmasked rocks, which are so common, and so little regarded for their metallic contents, that in Singapore they are used to macadamize the roads, contain often nearly 60 per cent. of pure metal.
The whole length and breadth of the peninsula, there can be little doubt, abounds in tin ore. The uniformity, we might almost say unity, of its plutonic character, warrants the inference that ores, found plentifully in many different and and distant localities where they have been sought for, exist also in the intermediate tracts which have not yet been examined. At the two extremities of the peninsular zone of elevation, Junk-Ceylon and Banca, tin sand is diffused in such quantity that its collection has never had any other limit than the number of persons employed in it. In Junk-Ceylon and Phunga, under a barbarous government, about 13,000 piculs are annually dug out of the soil. In Banca, under a European government, but without any improvement on the usual Chinese mode of excavating, washing, and smelting, the production has increased from 25,000 piculs, in 1812, when it was a British possession, to 60,000 piculs.
At numerous intermediate localities throughout the peninsula tin is obtained ; and when we consider the despotic, rapacious, and, too often, remorseless character of the native governments, the consequent failure of all attempts to introduce European or Chinese capital and system into the tin mining, and the robberies and massacres which, from time to time terrify and scatter the little communities of needy Chinese in whose hands it has remained, the wonder is, that so much metal should find its way to the market. In the Siamese countries north of Kedah, and in Kedah itself, which has been so long in a state of anarchy, it is sparingly extracted. From Perak 9000 piculs per annum was formerly exported, but the produce has now greatly diminished, owing to the miserable state of the country. Sálángor and the adjacent inland states yield about 1000 piculs. The eastern countries from Kalatan to Pahang yield about 11,000 piculs. The present produce of the whole peninsula, in- , cluding Sinkep and Linga, the only two islands of the Johore Archipelago where it is now sought for, is probably above 40,000 piculs. The produce for many years past has ranged between that quantity and 30,000. The peninsular range, therefore, including Banka, yields upwards of 100,000 piculs, so that it equals, or exceeds, that of Cornwall (6000 tons), and may be expected to increase steadily.
Seeing that tin is procured in all parts of the peninsula where it is sought for, and, in proportion to the enterprise and labor which are devoted to the search, we may consider the entire zone as a great magazine of tin. It is, in fact, incomparably the greatest on the globe. Johore might have seemed to offer an exception to the apparent universality of the distribution of oxyd of tin, if its geological affinity to Banca, the fact of tin having from time to time been found in several places, and for many years having been got in considerable quantity in Malacca, had not afforded the strongest presumption that its want of inhabitants and government was the cause of its nonproductiveness. The last eighteen months, however, have placed the matter beyond doubt, and given a striking proof at once of the metallic fertility of the country, and of the little attention which this branch of industry has hitherto met with in the British settlements. In 1845, Malacca, an integral part of Johore, and having the same geology as the rest of the country, produced about 450 piculs of tin. In the succeeding year the interest of some Chinese of capital was excited in the subject, and more vigorous and extensive ope. rations were commenced. In 1846 above 1400 piculs were procured, the greater part from 39 pits in one valley. In 1847 the produce appears to have been from 4000 to 5000 piculs. In 1848 it will probably rise to between 5000 and 7000 piculs, for the government tithe upon it for the year has been rented for the unprecedented sum of 8190 Sp. dollars ; the revenue from this source having been, in the two preceding years, $1020 and $3345 respectively.
Nothing can better show how entirely the metalliferous character of the peninsula has escaped the mining enterprise of private European capitalists, than the fact, that in the Island of Singapore, where we have a line of junction between plutonic and sedimentary rocks, of above 20 miles in length, where tin was found in former years in at least two localities and where the same iron ore, with which it is associated in Banca, abounds both in the igneous and aqueous rocks- no interest has ever been awakened in the subject. In the peninsula and Banca, tin has hitherto been procured by digging pits in alluvial tracts where the ore is found, generally intermixed with quartz particles, in a state resembling sand, varying from fine to coarse, and may properly be considered stream ore. Large specimens are found with the ore, adhering to, and partially invested with, quartz. We are not aware that it has ever been actually seen in the solid rock in the peninsula, but in Banca it is found associated with iron ore in veins in the granite. A Dutch writer also describes whole layers as occurring in some mountains, which consist parily of granite, but in the centre principally of layers of sandstone and quartz, in which iron ore also appears. In the more purely granitic mountains, it seems to have been observed in quartz at the junction of the granite, with the iron-veined sandstone strata. In the Isthmus of Krá, it has also been found at the junction of sandstone and granite. In Cornwall, it appears to be dependent on granite.
The finest ores of Banca yield as much as 80 per cent. of metal the common sorts from 40 to 60. The quality of the peninsular ores has not been ascertained so carefully ; we are not aware that more than 70 per cent. have been ever obtained.
We have dwelt, at some length, on tin, because it is the principal natural production of the peninsula, which derives from the fact of its being the greatest stanniferous tract in the world-an importance, economically, which has never been sufficiently appreciated. The existence of tin in Banca was unknown until 1709, when it was accidentally discovered. Now its produce doubles that of the peninsula, although the latter has a surface 18 times larger. The reason is not a mineralogical one: it is because in Banca the Chinese are stimulated, furthered, and protected, by a strong government which directly interests itself in their operations.
Gold is found in the peninsula, but whether from inferiority of enterprise, or natural deficiency, not in such abundance as in those parts of the adjacent countries of Sumatra and Borneo, where it is systematically dug for. The present annual produce is probably about 20,000 ozs. In all the larger specimens which we possess, or have seen, it is disseminated in small particles, and streaks, in quartz. Like the tin ore, it has not been seen in the undisintegrated state. Copper, silver, and arsenic, have been detected in Banca, but apparently in small quantities.
6. On an Impression of the Soft Parts of an Orthoceras.—The accompanying figure represents a specimen from a bed of shale alternating with compact limestone, near Cincinnati, Ohio, described by Mr. J. G. Anthony in the Quart. Jour. of the Geological Society, 1847, p. 256. Mr. Anthony observes, that the Orthocerata of the locality were associated with numerous fossils of the “ Hudson river group," and they were remarkably well preserved, the Lingulæ being erect, as if entombed in the position in which they lived ; the trilobites unusually perfect. On the Orthocerata, he remarks, that they frequently measured over three feet in length. “They all appeared more or less compressed, as if by the weight of the superimposed strata, and their diameter when thus flattened was frequently over six inches. The surface was often coated with a black substance, like paint; where this was removed, it appeared rough, almost like sha. green. My attention was however particularly drawn towards the
smaller specimens, each of which was enveloped in a sac, an appear. ance which I had never before noticed in connexion with these remains. This sac was of an oval form, about twice the diameter of the enclosed Orthoceratite, enveloped its whole length, was like it flattened, and had a longitudinal depression through its entire length. Upon seeing it, the idea was at once suggested that here was a solution of the question, never before determined, with regard to the form and texture of the body of the Orthoceratite. Though very widely distributed through various strata, yet the soft parts have been so completely destroyed by time and circumstances, that no discovery of them had been hitherto made, by which even a surmise could be formed of the organization of the animal. *** From the present discovery, we may reasonably suppose that they were furnished with a fleshy body, like the Sepia of the present day and its kindred cephalopods, or perhaps like the Belemnite of the antediluvian creation with its accompanying ink-bag. If they were provided with this latter apparatus, might not the black coating so common upon them be a deposit from that dark liquor ?" **
We have received a communication on Mr. Anthony's paper, from Mr. James Hall of Albany, who takes the ground that what is represented as due to the soft parts of the Orthoceras, is a result of concre. tion about the fossil. He mentions and figures numerous examples of similar appearances about fossils of various kinds, Orthocerala and others, which are nothing but a result of a concretionary structure ; and states that such forms are most common in the fine soft shales. The striated surface and bilobate form are common in the New York specimens. Moreover, it is doubted that the “soft parts could be. come petrified, or retain their form sufficiently during the decay which immediately follows death to give it to the enclosing material.
7. Effect of Fusion on the Density of Rocks.- In the last volume, p. 258, some facts are given relative to the change of density in different siliceous minerals, in consequence of fusion and their assuming a vitreous state. Delesse has experimented upon this subject, and gives the following table containing the diminution of density for the differ. ent rocks mentioned: (Jour. de Pharm. et de Chem., xiii, 68.)
Granites, quartzose porphyry and granitoid rocks, 9 to 11 per ct.
quartz, and having a base of albite, oligo 8 to 10 "
clase, andesite, Diorile and dioritic porphyry, · · Melaphyre, · ·
. 6 to I rachyle, . . . . . - - 4 to 5 " Ancient volcanic rocks and basalt, .
3 to 4 " Modern volcanic rocks and lavas, .
- 0 to 3 6 8. Talus Slopes.- In the chains of the Vosges and Jura, Leblanc found no talus exceeding an inclination of 35°. This slope, he ob. serves, is most rigorously, the inclination of the diagonal of a cube. The density of the material has no effect on the slope, as the ava. lanches of snow and fall of rocks take the same slope. Some rough rocks, as trachyle and sandstone debris, may form a declivity of 37° 10 39o. A talus of 42° to 45°, is not one of stable equilibrium.