FOSSILS AND SEMI-METALS.- -THEIR USES AND QUALITIES.

purposes of art. Molybdena is a species of lead which is used in pencils. It is very scarce; but such as has been discovered, is not inferior to the molybdena of Cumberland. It has been taken from Wheal Crafty, in the parish of Camborne. Hitherto it has been found only in small masses; its colour is of a light grey, occasionally variegated with red; it feels greasy, and stains the fingers with a touch. A piece of rosin rubbed with it becomes positively electric. The quantity hitherto discovered has been too small to apply it to mercantile purposes.

Manganese has been discovered in large quantities in various parts of Cornwall. It is raised and rendered fit for the market at a trifling expence; but hitherto the price has not warranted even the trifling exertions that have been made; nor, unless some new market shall be discovered, does it seem probable that the demand will ever bear a due proportion to what Cornwall can supply. It is a ferrugineous mineral, and is used to attemper glass, and bring it to its proper lustre.

No mineral substance in Cornwall has more frequently occupied the attention of the naturalist, and the art of the chemist, than mundic. This has sometimes been called marcasite, and sometimes pyrites; but mundic is the most familiar name. Scattered throughout all the mining districts, it has been found adhering to most metallic bodies, and exhibiting every variety of colour. Many of our waters are strongly impregnated with its noxious principles, and are of a red turbid colour. Arsenic, sulphur, vitriol, and mercury, are its constituent ingredients. These being communicated to the streams, so far pollute them, as to kill the fish within them. Dr. Borlase mentions that a flock of geese in the parish of Ludgvan having drunk of a river at a time when it was strongly tainted with mundic, nine of them died immediately on their return to the bank. He also mentions an instance of a man having washed a wounded leg in a stream of mundic water, which brought on a gangrene that terminated in his death. Mixed with earth and thrown upon the soil, it destroys all vegetation, and corrodes iron by means of the vitriol included in its composition. The care of the burning-house, in which ores are roasted to separate the arsenic from them, is one of the most dangerous employments in which the managers of metals can engage. The sulphur which concealed the arsenic, being consumed by fire, the poison becomes dispersed; and tainting the air with its noxious effluvia, operates within the sphere of its activity upon animal and vegetable life. Ores committed to the furnace for purification, must not be heated sufficiently to bring them into a state of fusion. The fire must be moderate, and frequently stirred with an iron rake; the arsenic, which has been separated by the heat, adheres to the head of the rake, resembling a whitish yellow dust, while other parts pass through the chimney in streams of pestilential vapour.

FOSSILS AND SEMI-METALS.-THEIR USES AND QUALITIES.

Although mundic by its specific gravity exceeds that of most other fossils, and has to all appearance the properties of a real metal, bearing a strong resemblance to brass, no flux hitherto discovered has been sufficient to reduce it to a metal. Some parts of it will melt in a very fierce fire; yet when cold, on being struck with a hammer, it may be reduced to powder. To fix it as a metal, no experiments have been omitted, and no expence has been spared. It has engaged the attention of the most celebrated characters in foreign parts; but every effort has hitherto proved abortive. Specimens of all the varieties that could be procured, were sent to Leyden to Dr. Boerhaave, to be examined by him; but his death taking place soon after, deprived the world of the gratification expected from his researches.

From the decomposition of mundic both sulphur and arsenic may be procured in tolerable quantities; but the trouble and expence of procuring them by other means, being much less than in these, no temptation is held out to the chemical adventurer.

In most places the chimnies of burning-houses are raised at a considerable distance from the houses themselves, to which the fumes are conveyed through subterranean passages. The orifice of the burning-house chimney at Polgooth Mine opens on the side of a distant hill, which seems too barren for cultivation. A large area of this steril spot is enclosed with a hedge, that no cattle may approach to crop the poisoned vegetation which lies in its vicinity. Were such precautions every where adopted, many of those fatal effects which have been experienced at different periods, might probably have been prevented.

CHAP. XVI.

Metals, particularly Tin and Copper.

SECTION I.

Vicissitudes of the Tin Trade.-Charter in favour of the Tin Trade.-Origin of the Stannary Laws, of Coinage, and Rights of Bounding.-Progress of Privileges.—Appointment of Officers.-Operation of the Stannary Laws.

IT appears from the best accounts, that, on the departure of the Romans from this country, the mines of Cornwall began to decline. The Saxons who succeeded them, being either ignorant of the value of metals, or wholly bent on ferocious conquests, treated them with neglect; and the distracted state of the country scarcely allowed the inhabitants an opportunity to open an intercourse with foreign traders. In the early periods of the Saxon dominion, these invaders had no authority in Cornwall; and after it was subdued by Athelstan, their attention was so much engaged with the Danes, who were become their formidable rivals in war, that they had little leisure to cultivate the arts of peace.

The victorious Danes displayed the same degree of inattention; so that the mines were utterly neglected until the Normans came. How far this new horde of invaders rectified the errors of their predecessors, seems very uncertain. By some they have been said to derive great advantages from the mines of Cornwall, but by others this fact has been viewed in a very doubtful light. It is however established upon indisputable evidence, that in the days of king John, the mines which were then considered as exclusively under his jurisdiction, were productive of very little profit. Committed to the management of mercenary Jews, by whom the revenues of the tin were farmed, the rights of the miners were rendered too precarious to keep alive that spirit of adventure upon which the existence of the mines invariably depends. Disgusted at his conduct, a momentary torpor again succeeded, and the trade languished to such a degree, that the annual produce which the king received amounted only to 100 marks. According to this valuation, the bishop of Exeter then received, instead of his actual tenth part, the sum of £6 13s. 4d. which sum he still receives from the Duke of Cornwall. Devonshire at this time was so far superior to Cornwall, that its tin revenues were let at £100 per annum.

FAVOURABLE CHARTER GRANTED TO THE CORNISH ADVENTURERS IN THE REIGN OF EDWARD I.

To prevent the tin trade of Cornwall from sinking into utter ruin, king John found it necessary to relax the severity of his former measures. He accordingly disforested such parts of the county as were subjected to the arbitrary forest laws, and placed the whole under the operation of the general law of the realm. To this he is said to have added a charter in favour of the miners, but its specific grants are not known. In the days of Richard king of the Romans, the mines of Cornwall were very rich, and highly productive to the revenue; and what tended to enhance their value was, that the mines of Spain were forbidden to be worked by the Moors; so that the tin trade of Europe was concentrated in these two western counties. The Jews were at this time farmed out by Henry III. to his brother Richard; in consequence of which, the profits of the mines became little less than an individual monopoly. This and the rapacity of the Jews, created discord, and caused a degree of languor which once more proved highly injurious to the trade. Edward I. to remedy these alarming evils, banished the Jews; but even this was insufficient to reanimate the mining adventurers, who had little encouragement, and even less protection, against royal prerogative.

The gentlemen of Cornwall, but more particularly of the Blackmoor district, in which the more productive mines lay, on perceiving the languishing state of the trade, and the disposition of government to revive it, boldly addressed themselves to Edmund earl of Cornwall, soliciting his interference in the establishment of some regulatious that should be permanent; beseeching him at the same time to confer upon them certain grants that were essential to the working of the mines. This application proved successful; the grants were conferred, confirmed by his own seal, and included in a charter, which gave certain privileges that had never been enjoyed before.

By this charter they were enabled to hold courts of judicature, to manage and decide all pleas of action, and all stannary causes, excepting such as affected land, life, or limb. At their own discretion they were permitted to hold parliaments, and to receive as their own due and property, one fifteenth part as a legal toll of all the tin that should be raised. In consideration of this privilege, these lords of the soil engaged to pay to the Earl of Cornwall one halfpenny for every pound of tin that should be brought to perfection; and that no suspicion of any fraud might arise, it was furthermore agreed, that all the tin thus raised and manufactured, should be brought to certain towns or places purposely appointed, to be weighed, coined, and kept, until the impost was paid. At the time when this exorbitant tax was consented to be paid in Cornwall, the tin raised in Devonshire was taxed no more than eightpence per hundred. To this charter there was a seal affixed, with a pick-axe and shovel in saltire. It was to be kept in one of the church steeples

ORIGIN OF THE CUSTOM OF RENEWING TIN-BOUNDS IN CORNWALL.

within the jurisdiction of its influence; and it had been seen by a gentleman with whom Mr. Carew was acquainted, but it was irrecoverably lost in his days.

But although Mr. Carew is supported by the authority of Camden, and followed by Dr. Borlase in the preceding account, the fact is otherwise stated by Tonkin in his notes on Carew, and he founds his statement on a book called "The Bailiff of Blackmore." According to this book, the charter was procured in the third year of Edward I. 1305, by several gentlemen dwelling chiefly in the several parishes of St. Austell, Luxulian, Lanlivery, St. Ewe, Roche, St. Stephens, St. Mewan, and St. Dennis. This charter, he asserts, was kept in the tower of Luxulian church, secured in a coffer with eight locks, and eight keys, each of which was kept by the parties of the parishes above named. He furthermore adds, that during the civil war, this charter, together with several other papers and rolls of much importance to the stannaries, was removed to Lostwithiel, where it was unfortunately destroyed in the year 1644, by the army of Essex.

It was about this time, and probably by virtue of this charter, that the rights of bounding, or of setting bounds to certain portions of land, for the encouragement of men searching for tin, were either first appointed, or at least more regularly adjusted than they had been before. According to these rights, if any man found shode or tin in any ground that was enclosed, but not bounded by another, the leave of the lord was to be first obtained before he could work. But if the land was bounded, then whether enclosed or not, to obtain leave of the previous bounder was all that the law required. And finally, if the land were neither enclosed nor bounded, then any person was at liberty to mark out bounds to the territory which he intended to examine; and observing the legal forms, he might then begin to search for tin. These bounds were in general formed by certain hillocks raised at the extremities of the given right, sustaining certain relations and bearings one towards another, so that lines drawn in given directions from them would circumscribe the rights to be secured. These bounds were to be renewed at stated periods, by cutting a small turf and placing it on the hillock; and, under some trifling variations, the same practice continues to the present day.

In the thirty-third of Edward I. the previous charter received an additional confirmation, which incorporated the tinners of Cornwall as a distinct body from those of Devonshire. Prior to this time the tinners of both counties held a kind of general convocation every seventh or eighth year on Hengston Hill, in which they concerted measures for their mutual advantage; but this was now succeeded by the chartered independence of both. By this new charter the Cornish tinners were permitted to hold two coinages annually, at Midsummer and Michaelmas ; and each tinner had the liberty of selling his own tin, unless the king chose to take 4 S

VOL. I.