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THE NICOBAR ISLANDS AND THEIR ABORIGINES
The Nicobar Islands and their Aborigines—The Islands—Coral Banks,
Nankauri Harbour - Population-Geology-Earthquakes-Climate-Flora
THE Nicobars lie 80 miles south of the Andaman group and 110 miles from Sumatra proper, and constitute a chain of islands 160 miles long, lying in a N.N.W. } W. direction, with a branch forking out from their centre N. by E. The area of the group is about 600 square miles, and it consists of some twenty islands, of which the principal are, Kar Nicobar, Batti Malv, Tilanchong, Chaura, Teressa, Bompoka, Kamorta, Trinkat, Nankauri, Kachal, Little Nicobar, and Great Nicobar.
Besides these, there are several small satellite islands: Great Nicobar possesses Kondul and Kabra; Little Nicobar, Milo and Menchal, with Treis, Trak, and Meroë further off; and lastly, near the south extremity of Tilanchong, there is the rocky islet named “Isle of Man."* There are villages on Kondul and Milo, but Batti Maly and Tilanchong are uninhabited.
Two large isolated coral banks occur-one near Chaura, with only if fathoms of water; and another, far more extensive, in the Sombrero Channel, with 11 fathoms of water above it.
Although the Nicobar Islands are scarcely ever heard of, the China Mail boats and other great ocean steamers pass almost in sight of them nearly every day, and they possess in the central group one of the finest harbours in the eastern seas. Nankauri Harbour has not only entrances on the east and west, that make it practicable for any sort of vessel in both monsoons, but these are further protected by the islands of Trinkat and Kachal respectively, which give sheltered anchorage outside the mouth of the harbour itself.
* After Mr E. H. Man.
By any other nation than the British it would be highly valued at the present time as a coaling station, but, owing to its proximity to the Straits Settlements, and the failure of the small islands around to produce anything more valuable than coconuts, it is completely neglected by its possessors, from both commercial and strategical standpoints.
The natives of the group number at present a few short of 6000 (to which should be added a possible 300-400 Shom Pen), and there are generally some 200 foreigners resident in the north during the trading monsoon. The islands increase in size as they are passed towards the south, but the contrary is the case with regard to population, which decreases regularly, island by island, with one or two exceptions, from Kar Nicobar in the north with 3451 inhabitants, to Great Nicobar with only 87.*
"The Nicobar Islands belong to an area of elevation which can be traced from the Bay of Bengal far into the southern seas,t and is characterised by two phenomena : first, the activity of the interior of the earth, showing itself in volcanic action; and secondly, the activity of the coralline animals, disclosing
Vide Appendix H. + “All along this great line of volcanoes are to be found more or less palpable signs of upheaval and depression of land ...; upraised coral-rock, exactly corresponding to that now forming in adjacent seas ...; unaltered surfaces of the elevated reefs, with great masses of coral standing up in their natural position, and hundreds of shells, so fresh-looking that it was hard to believe that they had been more than a few years out of the water.
“The width of the volcanic Its is about 50 miles; but, for a space of 200 on each side of them, evidences of subterranean action are to be found in recently elevated coral rock or in barrier coral reefs, indicating recent submergence."-Cf. “Andamans," The Malay Archipelago, A. R. Wallace, pp. 5, 6.
itself in the formation of that kind of coral reefs known as fringing or coast reefs. The islands occupy a gap without volcanoes between the volcanic ranges of Sumatra, and Barren and Narkondam Islands, and the occurrence of young volcanic rock in them is improbable. They are distinctly characterised as a portion of the chain of oceanic elevation which began in former geological periods and still continues, by the upheaved coral banks, and by the continuous formation of coral reefs. The synclinals and anticlinals in the geological structure of the islands are coincident with the direction of the great geological line of elevation which connects the northern part of Sumatra with the Andamans.
“ Among the geological formations of the Nicobars, three are the most important :-(1) An eruptive serpentine, with gabbro formation. (2) Marine deposits, probably of a younger Tertiary age, consisting of sandstone, slates, clay marls, and plastic clay. (3) Recent coral-reef formations.
"The serpentine and gabbro formation is characteristically of an eruptive nature. The Tertiary sandstones, slates, and clay marls appear forcibly broken through ; their strata is partly inclined, partly bent in flat, parallel, wave-like undulations. These rocks are accompanied by coarser and finer breccias, composed of angular fragments of these same rocks, and they can partly be regarded as friction breccias, partly as sedimentary tufas, in which beds of an argillaceous marl are interstratified. The eruption of these plutonic masses appears therefore to fall in a time when the formation of the marine deposits was partially completed, partially still in progress. They broke through on lines of fracture, of which the principal strike from S.S.E. to N.N.W. agrees with the longitudinal extension of the islands. On the middle islands the serpentine and gabbro attain their greatest development: on Tilanchong, Teressa, Bompoka, Kamorta, and Nankauri, they form bare hill ranges of 200-500 feet, and their configuration often marvellously resembles that of younger volcanic formations. The elevatory power has, however, acted most strongly on the southern islands, and has here upheaved sandstones and slates to heights of 1500-2000 feet above sea-level; on the northern islands the same power was, on the contrary, weakest.
“The clay marls of the northern and central islands (Kar Nicobar, Teressa, Bompoka, Kamorta, Trinkat, and Nankauri) and the sandstones and slates of the southern (Kachal, Little and Great Nicobar) appear to be only petrologically different products of one and the same period of deposition. There are, at the same time, very few materials from which the age of the marine formation could be determined, as the only fossil remains which have been found in their strata are fragments of driftwood changed to brown coal, plants resembling Fucoids, Foraminifera, and Polycistina. All these indicate more or less distinctly a young Tertiary age.
"We find a repetition of the geological condition of the Nicobars on the southern coast of Java and the south-west coast of Sumatra,
“The third principal formation of the Nicobars are coral formations belonging to the most recent or the present period. Coral banks of great thickness are found on Kar Nicobar, Bompoka, Trinkat, and other islands. They consist partly of compact coral limestone, partly of a coral and shell conglomerate upheaved 30 or 40 feet above the present level of the sea. On all the islands the original area is to be observed enlarged by coral land which is only separated by the higher sand-dunes along the shores from the still continuing formation of the coral reefs surrounding all the islands in the character of fringing reefs. Although these raised coral banks are decided evidence of the long-continued upheaval of the islands—that, in connection with the eruption of the serpentines and gabbros—the formation of the flat coral lands elevated a few feet only above the sea, can, on the other hand, be explained by the accumulation of coral fragments, of sand and shells, by the waves and breakers on the shallow surface of the fringing reefs.”*
Coal of a brown variety has been found in Little Nicobar, Treis, Milo, and Kondul, but everywhere in isolated masses and single fragments, showing traces of rolling, met with here and there without order, in sandstone and slate, and evidently derived from driftwood.
The only traces of minerals discovered have been ores of EARTHQUAKES
* Vide paper on the “Geology of the Nicobars," by F. von Hochstetter, translated by Dr Stoliczka, Proc. Geol. Survey, India.
copper and iron pyrites, finely disseminated through dioritic and serpentine rocks. The possibility of the occurrence of copper ores in the eruptive formation cannot be denied, but no discovery has yet been made which would indicate it. On the other hand, the islands are rich in useful building materials. The sandstone of the southern islands must give excellent working stones; the plastic clays of the north could, doubtless, be worked into bricks or pottery; the natives of Chaura largely employ it in their earthenware manufactures.
Although the islands are generally beyond the sphere of cyclonic disturbances, they have more than once experienced the effect of earthquakes. One of the most remarkable of these is said to have occurred from October 31 to December 5, 1847, when fire is reported to have been seen on one of the mountains of Great Nicobar. Part of the northern coast of the latter, especially in the vicinity of Ganges Harbour, sank beneath the sea, and for long the locality was deserted by the aborigines.*
On December 1881, an earthquake, felt also at the Andamans and throughout the Bengal Sea generally, caused extensive damage in Kar Nicobar to the coconut groves and huts of the natives. Vents were opened in the sandy soil; inland, trees were overthrown; sea-waves broke on the island, and at the village of Mūs, water rose into the houses of the Burmese traders, which stood on platforms 24 feet high.
There was another earthquake at Kar Nicobar in November 1899, when strong, but not alarming, shocks, lasting ten minutes, were experienced. The last occurred on September 18, 1900, when two heavy and severe shocks, each lasting five minutes, were felt throughout the island, but caused no damage.
The climate of the Nicobars is more uniform than that of the Andamans, for it is less diversified by wet and dry seasons, heat and cold, and in this respect resembles that of the Malay Peninsula at the same latitude. The prevalence of malaria renders the group unhealthy alike for foreigners and, in certain localities, for the natives, and all the attempts at settlement
* Vide p. 137