ANGLESEA, or ANGLESEY, (the Mon or Moneg of the Welsh, the Mona of the Romans) an insular county of North Wales, about 24 miles in length, and 17 in breadth, containing four market towns, and 74 parishes. It returns two members to parliament, one for the shire, and another for Beaumaris, the chief town. On the south-east it is separated from Caernarvonshire, by the narrow channel Menai, and is bounded on every other side by the Irish Sea. Along the Menai it is adorned by gentlemen's scats and extensive plantations, forming a beautiful contrast to 'I:,d scenery of Snowdon, and 'other lofty mountail ) opposite coast. The climate is, however, IK.Iiiit' y unfavourable to the rearing of wood; and as we advance into the island, it gradually becomes destitute not only of trees, but even hedges, assuming a naked and unpleasant aspect.
The face of the country is in general level, intersper with low craggy hills, composed chiefly of lime stone, a purple wavy slate, or breccia, and watered by numerous rivulets. The soil is of three kinds : a black vegetable mould, a sandy soil, or a stiff reddish clay, and though shallow, i2 exceedingly fertile, producing great quantities of Morn, and supporting numerous flocks of cattle. In favourable years this island is sup posed to export nearly 100,000 bushels of grain. It also sends annually several thousand head of cattle to the English market; they are driven to port Aethwy, the principal ferry to Caernarvonshire, and there com pelled to swim across the Menai. The cattle are some times drifted by the tides to a considerable distance ; but boats, which attend them during the passage, pre vent the occurrence of any serious accident.
Of the several productions of Anglesea, its copper ores are by far the most important. The Parys moun tain, in which these are contained, is about a mile in length, and of a most desolate aspect, producing no shrubs, and hardly any plants. The ore is found a few feet front the surface, and instead of being deposited in veins, as is generally the case in metallic mines, forms a connected mass of unknown extent, constituting the great body of the mountain. The mode of extracting it is therefore somewhat peculiar. The mineral is laid bare, and is then wrought in the same manner as stone-quarry. An immense hollow or excavation has been thus formed, perfectly open above, and atending to several hundred feet in length and breadth, and in some places 300 feet in depth. In this the miners gene rally work, exposed to the weather, by which means they escape the diseases to which such persons are com monly subject. The sides of the excavation are nearly perpendicular ; but several galleries have been dug into them, where a richer vein of the ore has been pursued farther than the rest. From the same cause, the bot tom is dug into deep pits, and exceedingly uneven. The colour of the inside varies according to the nature of the ore, from a dusky yellow to a beautiful green, or deep blue. The yellow sulphurated ore of copper is that which most ,abounds in these mines. It generally contains 25 per cent. of sulphur, from 25 per cent. to q- per cent. of copper, and consequently from 25 to 484 per cent. of refuse. Besides this, some other ores of copper occur, such as malachite, or green and blue carbonates of copper ; black ore, containing copper, galena, and calamine ; native copper in minute quanti ties, and some specimens of native sulphur. The ore, procured annually from these quarries, amounts to the astonishing quantity of between 40,000 and 80,000 tons.
It is partly dug by pick-axes, partly blasted by gun powder ; and afterwards broken by hammers into small pieces, preparatory to its being roasted. The kilns in which it undergoes this operation, are of two forms. In the older kind of kilns, the ore is piled between two parallel walls, several yards in length, six feet high, and about ten feet distant, and arched over along their whole length, forming the body of the kiln. In the same line w ith the body of the kiln. is another chamber of the same dimensions, and similarly vaulted, connected to it by three flues : this t hambp.r.' 'mended for collecting the sulphur. The ore in th is set on fire by a small quantity of coals, and thNeffilthustion is afterwards main tained by the oxydation of the metal, and the conversion 44 a portion of a sulphur into sulphuric acid, which com bines w ith a part of the metal, forming sulphate of cop per. The heat produced by this combustion converts the remaining portion of the sulphur into vapour, which is received into the condensing chamber, and falls down in the form of the finest flowers of sulphur. Later kilns arc in form similar to lime-kilns, having contrivances by which the ore can be removed as it is roasted, and fresh ore added. In these the floor of the condensing cham ber is on the same level with the top of the ore, and thus a greater facility is given to the escape of the sulphure ets vapour from the kiln. The quantity of ore which is put at one time into a kiln, amounts to several hundred tons, and requires about six months to complete the operation. The ore, after being roasted, is pressed and washed, to free it from impurities, by which it is gene rally reduced to of its former quantity ; and the water becomes impregnated with sulphate of copper. The richer ores are then dried, and exported to reverbora tory furnaces in South 'Wales and the neighbourhood of Liverpool; while the poorer ores, which cannot so well bear the expense of carriage, are reduced in furnaces erected on the spot. These are charged every five hours with about 12 cwt. of the washed ore, which produce cwt. of rough copper, in which state it is exported ; and at the subsequent refinings reduced to about one-half the quantity. The water which filters through the crevices of the mine, is highly impregnated with sulphate of copper, and furnishes a source from which the metal may be procured with more profit than even from the crude ore. It is pumped up from the bottom of the mine, and, along with the water in which the ore has been washed, is placed in rectangular pits, about SO feet in length, 12 in breadth, and 2 in depth In these pits are immersed pieces of iron, which, by combining with the sulphuric acid, precipitates the copper in the form of a reddish powder, slightly oxydatcd. The peecipitate, if pure, ought to give 38 per cent. of pure copper, but, in consequence of being mixed with clay, returns only 50 per cent. Several of the pits are connected with a shal low pool, into which the water is let off, after the preci pitation of the copper has been effected. Here, by ex posure to the air, the sulphate of iron, which is held in solution, is converted into an oxy-sulphate; and as the latter salt contains less iron than the former, the excess of iron is deposited in the form of a yellow ochre, which is dried, and exported to Liverpool.