251 XXV. REPORT ON THE TIN OF THE PROVINCE OF MERGUI. By Captain G. B. TREMENHEERE, Executive Engineer, ["Journal of the Asiatic Society of Bengal," vol. x. pp. 845-851.] I. THE tin of this province has not been sought for since the Burmese took possession of the country from their Siamese neighbours. Under the rule of the latter, or during the period at which Tenasserim was an independent State, extensive works for tin were carried on. It occurs chiefly in the beds and banks of streams issuing from the primitive mountains, which form the principal feature of this peninsula; portions of the banks of streams in which it is found are in some instances riveted with rough stone work, to confine the water for washing operations; and the ground on either side, for many miles along their course, is penetrated by innumerable pits from eight to ten and twelve feet deep. Traces of the work of many thousands of men are evident in several places. These pits are not connected with one another, but seem to have been sunk by separate small parties of men, to whom probably definite tasks were assigned, with a view of tracing the tin ground, and of extracting the gravel with which the tin is mixed. Their variable depth and the amount of labour expended on them is a tolerable indication of the success with which this has been pursued, and of the places in which ground might be again perhaps opened with advantage. 2. The streams themselves are rich in tin, which may be collected from their beds in considerable quantities. The process by which it has been deposited for long periods, and for many miles along the line of valleys through which they flow, appears to be in active operation at the present day. Crystals of the peroxide of tin washed down by the rivers, and deposited with sand gravel in their beds, may, by changes of the river's course during the freshes, be quickly covered with a few feet of gravel and soil. The older deposits have, as far as my observation extends at present, the same alluvial character, and it would be well in future operations to have regard to the levels in which the streams may have formerly run. The first of these localities which attracted my attention was the Thengdon river, issuing from the primitive mountains in the immediate neighbourhood of the coal mine on the Great Tenasserim river. I visited this river in the course of my survey of the coal basin, and found pits in great number along its banks, of the existence of which I had been previously informed, though the object for which they had been dug was not known to my informant. On washing some of the gravel from the bottom of one of the pits, a small quantity of tin was found. 3. A Shan was subsequently sent there, and collected 11,889 grains of tin of the native peroxide in the course of an hour and a half. Specimen No. 1, which is equivalent to 19 ounces and 198 grains of pure tin. 4. After leaving the vicinity of the coal mine, I proceeded down the river, and was accompanied by the Shan, who had been employed in tin-works in the Straits, and to whom several tin streams in the Mergui province were known. These are situated chiefly on the Little Tenasserim river, into which they empty themselves. The first and most accessible is the Thabawlick, which unites with the Thakiet three miles above the junction of the latter with the little Tenasserim. The mouth of the Thakiet is eleven miles from the town of Tenasserim. 5. The access to this tin ground is by land in the dry season. Landing at the village of Thakiet, I proceeded on foot eight miles, and reached the Thabawlick. 6. The intervening ground is for the most part flat. After passing a marsh of some extent there is a low ridge of hills, which presents, however, no obstacle to land carriage of any description. The face of the country is, as usual, except in marshy places, thickly covered with jungle trees; but the wild elephants' tracks are open and convenient. During the monsoon, boats carrying 100 bags of rice, can ascend the Thabawlick to the place alluded to in one day. The tide is felt about six miles from its mouth. 7. Having arrived at the spot at a point known to my guide, and at which he had the previous year stationed himself for a few months for the purpose of collecting tin, I found numerous pits and old cuttings from which tin had been formerly obtained. It is found in layers of gravel immediately beneath the soil. The surface is undulating, and during the wet season streams of water could have been conveniently conducted near the excavations for the purpose of washing the gravel. 8. The guide stated that crystals of tin could be in this manner separated by the hand without the usual aid of the washing-trough. The rains not being at that time sufficiently advanced for that purpose, I did not succeed in obtaining any tin from the pits. The line of deposit of the richest stanniferous gravel has been probably influenced by many causes, and the chances of finding it are much the same as those to which other undertakings of this nature are subject. A few trials, however, across the low ground through which the hill streams pass, would enable the speculator to follow its course. 9. The time of the tin-washer was, I found, much better occupied in seeking for tin in the bed of the river. He was assisted by one man, who disturbed the sand and gravel with his feet to as great a depth as he could thus accomplish, when a conical and shallow trough, about two feet in diameter and ten inches deep, was filled with the same, and washed in the stream by a circular motion, so as to get rid of the gravel and lighter particles, leaving the crystals of tin to collect, by their gravity, on the apex of the hollow trough. Each filling and washing occupied on an average six minutes. One washing produced 1,041 grains of native peroxide of tin in six minutes. Specimen No. 2, equivalent to 1 oz. 335 grains of pure tin. ditto ditto 1,265 ditto. 31 grains of pure tin. ditto 1,785 One 10. The produce of a day's labour of two men would be, according to the above trial, equivalent to 5 lb. 2 oz. 464 grains of pure tin, at the cost of 12 annas, exclusive of the expenses of reduction to the metallic state. This process, from the pure state of the mineral, is extremely simple and inexpensive. The tin. collected in the trough would require one more washing to remove particles of sand, &c., and charcoal is the only fuel required for its reduction. The pieces or ingots of tin in the shape of the frustrum of a cone (specimens Nos. 7 and 8), which are manufactured at the Rehgnon mines, on the Pak Chum river to the southward, and exchanged there for goods at 4 annas each, weigh 1 lb. 2 oz. 383 grains; and their value at Mergui, where the average price of tin is 85 rupees per 100 viss, of 365 lbs. 4 annas 4 pie. The value, therefore, of 5 lbs. 2 oz. 464 grains, or the day's work of two men, would be 1 rupee 8 annas 4 pie. The cost cf collecting being 12 annas, leaves 12 annas and 4 pie for the cost of the reducing process, and for profit on the labour of two men. II. On the morning after reaching the Thabawlick I traced the tin ground for a mile in a N.N.E. direction. The pits are in some parts more abundant than in others, and I was informed that they occurred and were thickly scattered throughout the entire course of the river between that point and the hills from which it issued, at the distance of an entire day's journey, if the windings of the river are followed. 12. The pits have not been worked since the Burmese took possession of the country. At the head of the stream there are said to be the remains of bunds constructed for distributing water for washing the tin, and the posts of a house still standing, which is supposed to have been occupied by a Siamese superintendent of the work there carried on. The season was too far advanced to enable me to prosecute my inquiries towards the hills on this occasion, and my attention was therefore confined to the spot from which I obtained the results detailed above. 13. Four other rivers emptying themselves into the lesser Tenasserim are said to produce tin, but none are so accessible as the Thabawlick. The following are the names of these streams, with their distances from the Thakiet river : The Khamoungtang river, one day by the little Tenasserim, and one march inland. Engdaw river, no road through the jungle. Kyeng river, two days by the river, and two days inland. Thapyn river, three days by the river, and one march inland. From the Khamoungtang specimen No. 9, weighing 2,890 grains, was collected in ten washings, but I did not visit the place myself. The size of the tin is larger than that collected in other places, though the produce is not equal in quantity. 14. After returning to Tenasserim I visited Loundoungin river, where tin was said to exist, but it turned out to be Wolfran sand, which had been washed down from the adjoining slate mountains, and was lying on the surface of the sandy bed of the stream. 15. In proceeding down the great Tenasserim river towards Mergui, I halted at Moetong for the purpose of visiting a tin ground which was said to exist near the range of hills to the N.E., skirting the open plain in which this place is situated. On penetrating to the hill itself I found it to consist exclusively of granite, with not a trace of another rock of any description. The dry beds of the water-courses consisted of granitic sand alone. There were many excavations for tin on the face of the hill. Several loads of gravel from the bottom of the pits and from the beds of the water-courses were carried to the river and washed, but the out-turn of tin was very small. There is no water within convenient reach. 16. The next spot visited was Kahan, a small hill near the Zedavoun Pagoda, on the right bank of the great Tenasserim river, eleven miles from Mergui. The tin occurs here under conditions differing much from that of the localities above mentioned. Kahan itself is the highest portion of a low ridge of hills, not more than 200 feet above the level of the river; it is composed of a soft, friable, white sandstone rock, the upper portions of which are decomposed and irregular. The surface gravel does not contain tin. It is found in the crystallized form, interspersed in decomposed granite, forming a vein about three feet wide, which is enclosed by the white sandstone rock, and dips down at a high angle with the horizon. Specimen No. 10, if its form be preserved, illustrates well the tin crystals imbedded in the decomposed granite, which are easily detached from the matrix. The specimen No. 11, from the same vein, of a yellow colour, is considered the surest indication of the presence of the mineral, and lies below the white, No. 10. Large scales of chlorite occur with it, which, as they are generally found where the tin is most abundant, is called by the natives the mother of tin. The face of the hill is in one spot scattered over with these, which appear to have been brought down from the vein with other matter from which the tin has been separated by the usual mode of washing. It will be noticed that the granite is completely decomposed, and that the crystals would be easily separated by washing. No tin has been raised here since the country came into our possession, but the locality has been known. It was worked during the Burmese rule, and valued as supplying the richest ore of tin. A Burmese residing near the spot pointed out the place where his operations ceased. He had followed the direction of the vein alluded to as well as he was able, and had driven a gallery underground in an inclined direction upwards, till the bank above fell in, when the mine was abandoned. He stated that he had procured considerable quantities of tin daily, and that he often found it in large masses mixed with the yellow ground above mentioned. Arriving at the spot where his work had terminated, I set people to excavate, and find, if possible, the vein which had been described. It was reached after about two hours' digging, at the depth of five feet from the surface of the cut in the hill in which we stood. In about a quarter of an hour a few baskets of the decomposed granite were removed down the hill, from which 3,900 grains of the crystallized peroxide of tin, equal to 63,176 grains of pure tin, specimen No. 12, were collected; and the next day 23,400 grains, equal to 2 lbs. 6 oz. and 100 grains of pure tin, were found in the same manner by one man's labour in excavating, one carrying down to the water, and a third washing. 17. This locality appears to be of very promising description, and I have little doubt that if the work were aided by ordinary |