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you the scite of the ancient town of Alcestre, which formerly stood close to this place. I have got some coins that were dug up there in a field of mine, which are quite fresh ; pero haps you would like to see them.”
DR. WALKER.—“ Very much indeed.”
Upon inspecting them they were found to be Roman coins, bearing the effigies of Titus Vespasian.
DR. WALKER." What have you there, Edward, that seems to have so fixed
attention. EDWARD.-“ An account of the coal mines of England, Sir." Dr. WALKER.-" Read it to me, I shall like
much to hear a description of them, as they lay completely out of our beat, and therefore, except from books, we are not likely to know much about them.'
OF COAL MINES.
EDWARD (reading.)—“ Coals are scattered, with a more or less sparing hand, over every continent, and almost over every kingdom of the globe. But in no country are coal mines so rich and frequent as in our native soil. M. Faugas de St. Fond, has ascribed the whole opulence of Eng. land to her coals, as being the very soul of her manufac. tures and consequent commerce. T'he coals of Whitehaven and Wigan are the most pure; and the cannel, or peacock, coal of Lancashire, are so beautiful, that they are suspected by some to have constituted the gagates, or jet, which the ancients ascribed to Britain. It is occasionally met with in Devonshire, as at Bovey-heath, resembling wood impregnated with bituminous matter of turf or peat.
" It is a common opinion among geologists, that pit coal is of a vegetable origin, and that it has been brought to its present state by means of some chemical process, with which we are still unacquainted. There is one circumstance which gives this opinion, though it may at first appear extravagant, considerable plausibility, we mean the existence
of vast depositions of matter, half way, as it were, between perfect wood and perfect pit coal ; betraying obviously its vegetable nature, and yet so nearly approximatiug to pit coal in several respects, that it has been generally distinguished by the name of coul. One of the most remarkable of these depositions exists in Devonshire, about 13 miles south west of Exeter, and is well known by the name of Bovey coal. It has been very well described by Dr. Mills, in the Philosophical. Transactions; and its vegetable nature has been ascertained by Mr. Hatchett, by a process of chemical experiments, by means of which he found both extractive and resin ; substances peculiar to the vegetable kingdom.”
EDWARD, (putting down the book:) —"What was it defined before it was classed among the vegetable substances, Sir ?”
DR. WALKER.—' Mineral. But, my dear Edward, you must glance over the subject, and chuse some one particular colliery, and that will give us some idea of all.”
Edward having slightly skimmed over the subject, selected the coal mines at Whitehaven, for their evening's amusement, and he began as follows :
“ The coal mines at this place are perhaps the most extraordinary of any in the known world. Sir John Lowther was the first that wrought them for foreign consumption; and it has been computed, that this gentleman and his son, Sir James, in the compass of a century, expended in one of them only, upwards of half a million sterling.
“ The principal entrance into these mines, for men and horses, is by an opening at the bottom of a hill, through a long passage hewn in the rock; which by a steep descent leads down to the lowest vein of coal. The greatest part of this descent is through spacious galleries, which are continually intersected by other galleries; all the coal being cut away except large pillars, which, in deep parts of the mine, are three yards high, and about twelve yards square at the base ; such great strength being there required to support the ponderous roof.
“ The mines are sunk to the depth of one hundred and thirty fathoms, and are extended under the sea to places where there is above them, sufficient depth of water for ships of large burthen.”
“ Astonishing !"* exclaimed Edward.
“. These are the deepest coal mines that have been hitherto wrought; and, perhaps, no other miners have penetrated
to so great depth below the sea, as those of Whitehaven. The very deep mines in Hungary, Peru, and elsewhere, being situated in mountainous regions, where the surface of the earth is elevated to a great height above the level of the
" There are here three strata of coal, which lie at a considerable distance above the other, and there is a communication by pits between one of these parallel strata and another. But the vein of coal is not always regularly continued in the same inclined plane, but instead thereof, the miners meet with hard rock, which interrupts their further progress. At such places there seem to have been breaks in the earth, from the surface downwards; and in some of them it may have sunk ten or twenty fathoms, or even more. These breaks the miners call Dykes ; and when they meet with one of them, their first care is to discover whether the strata in the part adjoining be higher or lower than in the part where they have been working; or, to use their own terms, whether the coal be cast down or up. If it be cast down, they sink a pit to it; but if it be cast up to any con.. siderable height, they are oftentimes obliged, with great labour and expence, to carry a level and long gallery through the rock, until they again arrive at the strata of coal.
“ Those who have the direction of these deep and exten. siye works, are obliged, with great art and care, to keep them continually ventilated with perpetual currents of fresh air. In the deserted works which are not ventilated with perpetual currents of fresh air, large quantities of damps and noxious exhalations are frequently collected; and insuch works they often remain for a long time, without doing any mischief. But when by some accident they are ignited, that is to say set. on fire, they then produce dreadful explo-. sions, and bursting out of the pits with great impetuosity, like the fiery eruption from burning mountains, they force along with them ponderous bodies to a great height in the air.
“The coal in these mines has several times been ignited by these fulminating damps, and has continued burning for many months, until large streams of water were conducted into the mines, and suffered to fill those parts where the coal was burning. By such fires several collieries have been totally destroyed, of which there are instances near Newcastle, and in other parts of England, as well as at Fife in
Scotland ; in some of which places the fire lias continued burning for ages.
“ In order to prevent as much as possible, the collieries from being filled with those pernicious damps, it has been found necessary, carefully to search for those crevices in the coal, from whence they issue out, and at those places to confine them within a narrow space: and from those narrow spaces in which they are confined, to conduct them through long pipes into the open air, where being set on fire, they consume in perpetual flames, as they continually arise out of the earth.
“ The late Mr. Spedding, who was the great engineer of these works, having observed that the fulminating damp. could only be kindled by flame, and that it was not liable to be set on fire by red hot iron, nor by the sparks produced by the collision of flint and steel, invented a machine, in which a steel wheel is turned round with a very rapid mo. tion, and flints being applied thereto great plenty of fiery sparks are emitted, that afford the miners such a light as enables them to carry on their work in close places, where the flame of a candle or a lamp would occasion a dreadful explosion."
DR. WALKER.—" Sir Humphrey Davey has invented a safety lamp upon such an ingenious principle that no danger is now apprehended from accidents of this kind."
EDWARD, (resuming his reading.)-“ But not so many mines have been ruined by fire, as by inundations ; and here that noble invention the steam engine displays its beneficial effects. It appears from pretty exact calculations, that it. vrould require about 550 men, or a power equal to that of 110 horses to work the pumps of one of the largest steam engines now in use, and thrice that number of men to keep an engine of this size constantly at work, and that as much water may be raised by an engine of this size, kept constantly at work, as might be drawn up by 2520 men by rollers and buckets, after the manner now daily practised in mines; or as much as can be borne up on the shoulders of twice that number of men, as is said to be done in the mines of Peru. So great is the power of the elastic steam of the boiling water in those engines, and of the outward atmosphere, which by their alternate actions give force and motion to the beam of this engine, and by it to the pump rods, which
elevate the water through tubes, and discharge it out of the mine.”
DR. WALKER." You have heard what the Negro said upon seeing one of those steam engines at work. • White man make every thing work, fire, water, earth, and air, and he boil water to make it work harder.'”
THE SCILLY ISLANDS, AND TIN MINES OF CORNWALL..
“ So much for the coal mines;” said Dr. Walker, now turn over, perhaps we may find something relating to the tin mines."
EDWARD._" Yes, Sir, here is an account of them, shall I read it ?" Dr.WALKER,- “ Pray begin;
but one word upon the tiquity of these Cornish mines. The Cornish tin mines were well known to those great navigators of antiquity, the Phænicians, who visited the British Isles for the purpose of procuring this useful, beautiful, and valuable metal. Hence the Greek name Cassiterides, or the Islands of Tin, which they bestowed upon Great Britain and Ireland. The Scilly Isles alone have retained the name of the Cassiterides, although they no longer exhibit symptoms of the precious metal, from whence the name is derived. Shut your book for the present, and order tea, and while we sip the fragrant beverage, we will make an ideal tour to those barren isles, after which we will resume our studies
upon mineralogy. “ The inhabitants of this unkindly spot are all new comers ; these isles contain no habitations worth notice; no remains of any Phænician, Grecian, or Roman art, either in town, castle, port, temple, or sepulchre. All are vanished. The few antiquities that remain are Druidical. Upon all the islands, (several of which are now without cattle or inhabi. tants) are the remains of hedges, walls, foundations of houses, and a great number of sepulchral burrows, which clearly prove that they have been cultivated, and consequently inhabited. That they were inhabited by Britons,