THE beds of coal dip from one yard in four, to two in three; they immerge between the estuary of the Dee, are discovered again on the south-fide of Wiral, in Cheshire, as if correfponding with fome of the Flintshire. They remain as yet loft on the northern part of the fame hundred, but are found a third time in vaft quantities in Lancashire, on the oppofite fide of the Mersey. Their extent from west to eaft, in this country, may be reckoned from the parish of Llanafa, through thofe of Whiteford, Holywell, Flint, Northop, and Hawarden. Our coal is of different qualities, fuited to the variety of demands of the feveral forts of founderies in the neighborhood. Sometimes is alfo found the peacock-coal of Dr. Plot, remarkable for the beauty of its surface, gloffed over with the changeable brilliancy of the colors of that beautiful bird.

ΤΗΣ

COAL.

CANAL COAL.

FREE-STONE.

BURNT ROCK.

THE beds of canal are inferior indeed in elegance to those of Lancashire, but greatly coveted by the lime-burners.

COALS were known to the Britons, before the arrival of the Romans, who had not even a name for them; yet Theophraftus defcribes them very accurately, at left three centuries before the time of Cafar; and even fays that they were used by workers in brass. It is highly probable that the Britons made ufe of them. It is certain they had a primitive name for this foffil, that of Glo; and as a farther proof, I may add, that a flint-ax, the inftrument of the aborigines of our island, was dif covered stuck in certain veins of coal, expofed to day in Craig y Par Monmouthshire; and in fuch a fituation as to render it very acceffible to the unexperienced natives, who, in early times, were incapable of purfuing the veins to any great depths. The artlefs fmelters of antient times made ufe of wood only in their operations, as we find among the reliques of their hearths.

Ar a short distance from the fhale appear the beds of freestone, first on the fide of the dingle Nant y bi, and from thence above the coal, terminating in the cliffs in the parts of Tre Bychton and Tre Moftyn, which are washed by the fea.

In the township of Tre Meftyn, near the fhore, is a cliff of a very fingular appearance, looking like the femi-vitrified lava of a volcano. The ftratum is in front univerfally changed in its difpofition, and run into a horrible mass of red and black; often porous, in all parts very hard. In it is a hollow, a vein in which was lodged the pyritical matter that took fire, which continued burning by its own phlogiston, (fee Bishop Watfon, i. 167, to p. 200.) and caufed the phenomenon. Its fury chiefly raged

towards

towards the front, and diminished gradually in the internal part of the bed; which, at fome distance within land, appears only difcolored. The ftratum is a fand-ftone of the common fort (Da Cofta's Feffils, 133.) I am informed, that these appearances are not uncommon in Derbyshire; and that Mr. Ferber, an ingenious Swede, and Mr. Whitehurst, our ingenious countryman, have taken notice of them in their writings.

I SHALL here introduce the mention of damps found in collieries, which are not unfrequent, and fometimes act with amaz ing fury, and fatal confequences. There are two species, the fuffocating, and the fire. The last is very rare in the le.......nes, unlefs in those parts where the fhale, or ftone attendant on coal, begins. The first kills inftantaneously, by its mephitic vapor, and is a difafter common to neglected vaults, and draw-wells. The other is inflammable, and burns and deftroys in a dreadful manner, as the colliers, through negligence in not fetting fire to the vapor before it gets to a head, do often experience. The most tremendous inftance was on February 3d, 1675, in a coal-work at Moftyn, which I fhall relate from the Philofophical Transactions; and fo conclude the account of our mineral concerns.

of

THE damp had been perceived for fome time before, refembling fiery blades, darting and croffing each other from both fides of the pit. The ufual methods were taken to free "the pit from this evil. After a ceffation of work for three days, the fteward, thinking to fetch a compafs about from the eye the pit that came from the day, and to bring wind by a fecureway along with him, that, if it burft again, it may be done without danger of men's lives, went down, and took two men ' along

T

A FIRE-DAMP.

along with him, which ferved his turn for this purpose. He was no fooner down, but the reft of the workmen that had wrought there, difdaining to be left behind in fuch a time of danger, hafted down after them; and one of them, more indifcreet than the reft, went headlong with his candle over the eye of the damp pit, at which the damp immediately catched, ' and flew up, to and fro, over all the hollows of the work, with * a great wind, and a continual fire; and, as it went, keeping a mighty great roaring noise on all fides.

'THE men, at first appearance of it, had moft of them fallen upon their faces, and hid themselves as well as they could, in 'the loose flack, or fmall coal, and under the shelter of posts; yet nevertheless, the damp returning out of the hollows, and ' drawing towards the eye of the pit, it came up with incredible 'force; the wind and fire tore most of their clothes off their 'backs, and finged what was left, burning their faces and hands; * the blasts falling so sharp on their fkin, as if they had been whipt ⚫ with cords. Some that had lefs fhelter were carried fifteen or * fixteen yards from their first station, and beaten against the roof of the coal, and fides of the pofts, and lay afterwards a good

* while senseless, so that it was long before they could hear or find one another. As it drew up to the day-pit, it caught one of the men along with it that was next to the eye; and up it comes, with fuch a terrible crack, not unlike, but more shrill, ⚫ than a cannon, that was heard fifteen miles off, with the wind, and fuch a pillar of fmoke as darkened all the fky over-head ' for a good while. The brow of the hill above the pit was * eighteen yards high, and on it grew trees of fourteen or fifteen.

"yards

yards long; yet the man's body, and other things from the pit, ' were seen above the tops of the highest trees, at left 100 yards. On this pit stood a horfe-engine, of substantial timber, and ftrong iron-work; on which lay a trunk, or barrel, for winding the rope up and down, of above 1000 pounds weight; it was ' then in motion, one bucket going down, and the other coming up full of water. This trunk was faftened to that frame with ' locks and bolts of iron; yet it was thrown up, and carried a good way from the pit; and pieces of it, though bound with iron hoops and strong nails, blown into the woods about; fo like'wife were the two buckets; and the ends of the rope, after the buckets were blown from them, ftood awhile upright in the air like pikes, and then came leifurely drilling down. The 'whole frame of the engine was stirred and moved out of its place; and thofe men's clothes, caps, and hats, that escaped, 'were afterwards found fhattered to pieces, and thrown amongst

the woods a great way from the pit.'

ANOTHER of these damps happened in the fame lands within ANOTHER IN 1751. my memory. In the year 1751, one man was beat to pieces in the bottom of the pit. Two others were taken up alive, but died foon after; and two others furvived, but were moft dreadfully burnt: and one who is now living, remains a dreadful evidence of the effects of the damp. All his fingers burnt off, and his vifage terribly disfigured.

I SHALL here describe agitations of the earth derived from other caufes, which, dreadful as they have been in diftant coun tries, have here occafioned little more than a momentary alarm. I have at this house felt four shocks of the earthquake. I shall T 2 relate

EARTHQUAKES.