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impending fhores; and its bottom fpread over with mountains and vallies like the land.

It is further to be obferved of the horrid effects of this convulfionthat as the primitive lands were more ponderous and less elevated than the bottom of the fea, the former would more inftantaneously fubfide into the ocean of melted matter, than the latter; therefore, in all probability, they became the bottom of the pofidiluvian sea: and the bottom of the antediluvian sea being more elevated, was converted into the pofidiluvian, mountains, continents, &c. This conjecture is remarkably confirmed by the vast number of foffil shells, and other marine exuvia, found imbedded near the tops of mountains, and the interior par:s of continents, far remote from the fea, in all parts of the world hitherto explored.'

In this manner, and by employing a caufe that appears adequate to the effect, and which is known, even at this time, partially to exift; the Author at once accounts for the fingular appearances which the prefent earth exhibits on and beneath its furface, for the general deluge, and for its ceffation; and this he does, without having recourfe to comets, a fudden alteration of the earth's center of gravity, and other violent and purely gratuitous affumptions. A difficulty however remains, which he next prepares to folve.

The remains and impreffions of marine animals have not only, as we have already obferved, been found in all parts of the globe; but it is likewife well known that the exuvia, &c. of fhell fifh which now inhabit only the feas between the tropics and near the line, have been frequently found here in England, and in various other parts very remote from their prefent native climates ; and fometimes depofited with as much order as beds of living shell fish are in the fea. Thus for inftance, the chambered Nautilus, and remains of the Hawkes bill, Loggerhead, and Green Sea Tortoife, of Alligator's teeth, and of various fhell fish, that now inhabit the Chinese ocean, or the Eaft and Weft Indies, have been found at Sheppy_ifland, Richmond in Surry, and different parts of England. Remains, likewife, or impresfions of Crocodiles have been found in Derbyshire, Germany, &c.

Though these remains were depofited in thefe places at the ara of the deluge, or in confequence of the elevation of the ftrata, in which they are found, from the bottom of the Antediluvian ocean; the Author conceives it to be repugnant to common fense to suppose that these bodies could have been tranflated from their native beds in a diftant climate, and brought into their prefent fituation by the waters of the deluge. He cannot admit that regular beds of oyfters, &c. for inftance, natives of the American feas, could have been removed some thousand miles from their original feats, and depofited here with as much order as is obferved in the beds of living shell fish. On the contrary,

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he affirms that they are now found in the very fame spot of the globe where they formerly lived and affociated: though fome of the fpecies do not, or perhaps cannot, exift in the fame latitudes, at prefent. The Author's attempt to folve the difficulty is principally founded on the following obfervation.

Animals might live, he alleges, in the primitive globe, univerfally covered with water, which cannot exift in the fame parts of the prefent globe, in confequence of the very great change in the temperature of climates, occafioned by the production of immenfe continents and mountains. From a confideration of the different properties of land and water, with respect to the tranfmitting or conducting of heat, the Author infers that the different regions of the primitive globe enjoyed a more equable température than the prefent, in confequence of the former having been uniformly covered with water, or containing iflands of small extent and elevation, and being thereby more extenfively adapted both to animal and vegetable life. On fimilar grounds he accounts for the longevity of our antediluvian forefathers; and ftill keeping an eye on Mofes, terminates his principal inquiry by a chapter on the poftdiluvian rainbow.

In the Appendix to this work are contained feveral curious particulars relative to the different ftrata of the mines in Derbyfhire, their arrangement, correfpondence, diflocations, and the changes they have undergone at different periods of time. Thefe obfervations are illuftrated by feveral plates, representing fections of them, in which their direction, fituation, depth, and other circumftances are fatisfactorily delineated. From this part of the work we cannot refift the temptation of extracting a few striking particulars.

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One of the most remarkable of these ftrata is that called toadfone, black-ftone, channel, or cat-dirt, as it is variously denominated in different parts of thefe mining diftricts. This ftratum the Author pronounces " to be as much a lava as that which flows from Hecla, Vefuvius, or Etna.' It is blackish, very hard, and of a clofe texture; contains bladder-holes like the fcoria of metals, and has the fame chemical property of refifting acids. It seems to be the product of a later period than that of the limestone ftrata which it repeatedly feparates; and between which it evidently appears to have flowed, as well as to have filled up the fiffures that lay under it. Thefe limeftone ftrata contain various metallic ores, as well as figured ftones exhibiting the impreffions of numerous fpecies of marine animals; fome of which are not known to exift in the British feas*:

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The impreffion of a Crocodile likewife was found in a stratum of this ftone, in one of the Derbyshire mines, a fection of which is given in the firit of the Author's plates.

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whereas this fubftance, which is as uniform as any vitrified matter of this kind can be fuppofed to be, neither contains minerals, nor figured ftones, nor has any adventitious bodies enveloped in it. Neither does it univerfally prevail, as the limeftone ftrata; nor is it, like them, cqually thick; but in fome inftances varies in thieknefs from fix feet to fix hundred.'

Another circumftance that feems to prove it a volcanic production is, that a ftratum of clay lying under it, has been found in various places, exhibiting the appearance of having been burnt, as much as an earthen pot or brick. On a comparison, no fenfible difference could be observed between this clay, and another portion of clay in a mine at Heynor common, which had been burnt by a ftratum of coal having been on fire underneath it. On this occafion the Author offers fome probable conjectures, to explain in what manner this lava was introduced between fuch immenfe ftrata of ftone; and why it did not force its way through the furface of the earth, according to the ufual courfe of volcanic operations.

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In this Appendix the Author makes a general and important remark, founded on the refult of his obfervations made not only in Derbyshire, but in Staffordshire, Shropshire, &c. It relates to the difference of fituation between the marine or animal exuvia, and the impreffions of vegetables. The fuperior or clayey firata, contain the vegetable impreffions, but exhibit no marine productions whatever : whereas the inferior or lime ftone frata, contain the exuviæ of marine animals, and no vegetable forms whatever. These circumftances, according to him, indicate the order in which the refpective firata were fucceffively arranged. The inferior lime ftone ftrata, containing marine productions only, must have been conftituted while the fea covered the earth: the fuperior, exhibiting impreffions of vegetables, must have been formed after that earth became habitable.

Some exceptions, however, to this arrangement are to be met with in Authors; particularly one, which Mr. W, quotes from Ray, that apparently contradicts the general order': but thefe, he confiders only as anomalies, occafioned by partial or local revolutions. In Derbyshire, one inftance only feems, at firft fight, to contradict his general rule. Numerous exuvia of fhell fish have been found in the fuperior ftrata, incumbent on lime ftone: but on examination it appears that these fhells are not marine productions, but of fresh water lakes, rivers, &c.; in fhort, they are the remains of horse muscles.

We cannot terminate our account of this performance without taking notice of a very extraordinary_phenomenon, that has frequently been obferved in fome of the Derbyshire mines here named; where the vein of ore is divided into two equal parts,

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parallel to the fides of a fiffure, resembling two flabs of marble, whofe furfaces, which have a high natural polish, are in contact with each other, though without the leaft degree of cohefion. The fingular circumftance relating to them is thus defcribed.

If a fharp pointed pick is drawn down the vein with a fmall degree of force, the minerals begin to crackle, as fulphur excited to, become electrical by rubbing; after this, in the fpace of two or three minutes, the folid mafs of the minerals explodes with much violence, and the fragments fly out, as if blafted with gun-powder.

Thefe effects have frequently happened, by which many workmen have been much wounded, but none killed, both in the Eyam mines and in that at Castleton.

In the year 1738 a prodigious explofion happened in the mine called Haycliff.

The quantity of two hundred barrels of the above minerals were. blown out at one blaft; each barrel, I prefume, contained no less than three or four hundred weight.

At the fame time a man was blown twelve fathoms perpendicular, and lodged upon a floor, or bunding, as the miners call it.

When the above explofion happened, the barrel, or tub, in which the minerals, &c. are raised to the furface, happened to hang over the engine shaft, which is nearly seven feet wide, and five or fix hundred yards from the forefield, or part, where the explosion happened; this barrel, though of confiderable weight, was lifted up in the hook on which it was fufpended; and the people on the furface felt the ground fhake, as by an earthquake.

Such are the effects which have frequently been produced in all the above mines: but from what caufe they proceed I have not yet been able to discover, nor even the leaft traces towards it.

When thefe wonderful effects firft happened they deterred the workmen for fome years from venturing to work the mines, but afterwards they availed them felves of this extraordinary property. A man would go to the forefield, give a scratch with his pick, and run away; by which means he loofened as much of the minerals as could have been done by common workmanship with ten men in three months.

Thefe curious obfervations I received from Mr. Mettam of Eyam, overfeer of the mines, who alfo addreffed the following account of them to Mr. George Tiffington of Winster.

"SIR,

Eyam, 2 July, 1763. "I fend you, by the bearer, two fpecimens of our flickenfides' containing all the variety of minerals where the explosions happen; they fly out in fuch flappits †, smooth on one fide. The explosions are fometimes heard to the furface, and felt like an earthquake; they frequently blow out all the candles in the mine, and fplit the ftemples into fplinters as fmall as the twigs of a birch beefom, to

*Slickenfides, fhining, as if polifhed by art, on one fide.

Slappits, fragments of the minerals burft out of the vein.

Stemples, joints laid across fiffures, when the minerals are cut out, by way of making a floor, on which rubbish is depofited, to fave the expence of railing it to the furface.

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the diflance of thirty or forty yards from the forefield §; others are broke, and fome of them become too short and drop out.

"The fmooth fides lie face to face, and have the appearance of being shot with a plane, confifting of various members. There is generally two of thefe divifions in our forefield at Haycliff, about cight or ten inches afunder, and a feam of white kebble in the middle of that space, half an inch thick, in which the miners rake down a sharp pointed pick until the crackling ceafeth; then they run away, knowing that the explofion will follow in a minute or two. Sometimes a noife is heard like the beating of a church clock, after which the greatest explosions happen. I am yours, &c. To Mr. George Tiffington,

Winfter.

WILLIAM METTAM."

We shall only add, that on the memorable first of November 1755, about ten in the morning, when the earthquake fo fatal to Lifbon happened, the workmen were greatly alarmed in these very mines. The rocks which surrounded them were so much difturbed, that foil, &c. fell from their joints or fiffures; and they likewife heard violent explofions, as it were of cannon. Being thus alarmed, they left their fubterraneous employment, and fled to the furface for fafety.'-On their return, however, they did not obferve any material change.

How far the prefent theory correfponds with all the phenomena we shall not undertake to pronounce: nor fhould our Readers draw any conclufions from this fhort abstract of a fyftem, the truth or probability of which depends' fo much on the relation and mutual connection of its several parts, and on the number and weight of the teftimonies produced in fupport of it. A well founded judgment can only be formed after an attentive perufal of the work itfelf; which contains many proofs both of the industry and ingenuity of its Author,

§ Forefield, that part of the vein under workmanship.

Kebble, a white opaque fpar, calcarious, but not apt to break into rhomboidal forms.

ART. XI. Mr. Orme's Hiftory of the Military Transactions of the British Nation in Indoftan. Vol. II. Continued: See our laft Review.

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T is with pleasure we recal the attention of our Readers to this valuable work, and, in further confirmation of the idea we have given of its uncommon merit, proceed to lay before them the Author's account of the battle between the English and French troops at Vandivafh: a battle not lefs interesting or memorable than that of Plaffey.

The distance from Tirimbourg to Vandivash is seven miles; the road leads from the N. E. to the S. W. The mountain of Vandivash lies in the fame direction, extending more than a league in length. The fort ftands two miles to the S. of the mountain, but nearer to the western than the eastern end. The French army was encamped directly oppofite to the eastern end of the mountain, at the distance

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