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in the Pentateuch of Mofes,* which cannot be dated lefs than 1400 years before Chrift. It is also mentioned by Homer, who had too accurate a knowledge of the progreffive improvement of mankind in arts and fciences to affign any discoveries to an improper age. But, when thofe mines are well examined, they exhibit internal teftimony of the remote, I had almoft faid the incalculable, period at which they have been wrought; for, in digging to the depth of fifty fathom, the miners frequently meet with large timbers still entire. These are vulgarly supposed to have been depofited there by the waters of the deluge: but that idea tends to violate M. De Luc's rational hypothefis, which fuppofes that deluge to have been effected by the finking down of the ancient continents; and, without going quite fo far back in the annals of time, we may reasonably enough conclude them to have been left there by Phoenician workmen, the props and pillars of the exhausted mines, especially when we read, in the fame author, that pick-axes, brafs nails, and other utenfils,

Numbers, chap. xxxi. v. 22.

† Homer's Iliad, lib. ii, v. 25.

are

are found, at the greatest depths, intermixed with those timbers.*

Tin is itself fo beautiful a metal, forms fuch elegant domeftic utenfils, the most elegant next to filver, and in the various proceffes it undergoes by fire makes so confiderable an ingredient in other manufactures, that the folicitude of all nations, and efpecially those addicted to commerce, to obtain it, is by no means to be wondered at. The great use indeed of tin, and the preparations made from it in the various branches of trade and manufactures, particularly in painting, gilding, and pottery, as well as in the science of chemistry, and anciently in that of medicine, though, from its poisonous qualities, generally and juftly rejected by the modern practitioner, is too well known to be here infifted on.

The Tyrians themselves are supposed, by folutions of this metal, to have greatly enhanced and fixed the beautiful colour of their purple dye, and our own manufactured broad-cloth is affirmed to owe its decided fuperiority in the markets of Europe to its being died in the grain, as it is called, in

* See Childrey's Natural History, p. 8.

+ See Pryce's Mineralogia Cornubienfis, p, 17.

YOL, VI.

Q

liquids,

9

liquids, where this metal has formed a principal ingredient.

There is a very clear and particular account given in the Philofophical Tranfactions of the method of obtaining and preparing this metal in the mines of Cornwall, which, though too full of technical phrases, known only on the fpot, to be inferted at length, may yet be acceptable to the mercantile reader, in the abridgement which is here prefented to him.

The ore is only to be obtained by the moft elaborate exertions of the miner. The veins defcend to very great depths, fometimes to the diftance of fixty feet from the furface, and it is often found imbedded in rocks, fcarcely penetrable by the tools of the workmen. It is also a labour of extreme hazard, from the arfenic with which tin is ftrongly impregna ́ted; and fulphureous damps and malignant vapours, exhaled around him, often interrupt. his progrefs through thofe regions of darknefs and peril. Superftition has added to the terrors of the scene, for, to ufe the exprefs words of my author, "The labourers tell ftories of sprights of small people, as they call them; and, that when the damp arises from the fubterraneous vaults, they hear ftrange

noifes,

noifes, horrid knockings, and fearful ham merings, Thefe damps render many lame, and kill others outright, without any yifible hurt upon them.”*

The ore is differently denominated as it is found in its more pure or mixed ftate. That which is called boll is properly the mine-tin, as it is obtained from the load, or vein, and it is ufually dug up in grains or chrystals of a black colour, the blacker the richer, and in lumps of various magnitude. Shode-tin is that which is mixed with ftony and earthy matter, found in maffes of much larger fize, and in the immediate vicinity of the vein. The ftream-tin ore is a name given to particles of the mineral, broken off from the load, running through high mountainous regions, by the waters of the deluge (fay the miners,) or by other impetuous floods, and carried by the violence of the ftream into deep valleys at a great distance. There, collected into heaps, they have, in different places, formed ftratą of confiderable depth and breadth, and lie intermixed with the gravel and clay which was torn away with them from their original bed, The fragments are found in the form of

* Dr. Morret on the Cornish mines, in Philofophical Tranfactions Abridged, vol. ii. p. 573.

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Small

fmall pyramids, of various planes, and are of different fizes, from the bignefs of a walnut to the finest fand. Of this fort, principally, well washed, ftamped, and purified by repeated fufion, is made the fineft grain tin, and its fuperiority to the metal dug from the mine arifes from its being free from the mundic, and other mineral fubftances, which generally impregnate and contaminate the latter.

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Having difcuffed the various kinds of this metal in its original state, we come to their mode of preparing, or, as the miners call it, dreffing, the tin. When the ore is dug out and landed, and the larger maffes are broken by men appointed to that duty, it is brought on horses, to the ftamping-mills; where, being placed in a great, wooden receiver, called the coffer, it is ground to fmall fand by maffy iron weights, faftened to the ends of strong beams of timber. These timbers are called lifters, are made of heart of oak, eight or nine feet in length, and being raised up and depreffed by means of a water-wheel, are precipitated down with prodigious force on the matter to be pulverized. The ore, thus reduced to powder, is, by an ingenious procefs, particularly defcribed in the paper referred

to,

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