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impending shores; and its bottom fpread over with mountains and vallies like the land,
• Ic is further to be observed of the horrid effects of this convulsion that as the primitive islands were more ponderous and less elevated than the bottom of the sea, the former would more inftantaneously subside into the ocean of melted matter, than the latter; therefore, in all probability, they became the bottom of the postdiluvian fea: and the bottom of the antediluvian fea being more elevated, was converted into the poldiluvian mountains, continents, &c. This conjecture is remarkably confirmed by the valt number of follil snelis, and other marine @xuvia, found imbedded near the tops of mountains, and the interior par:s of continents, far remote from the sea, in all parts of the world hitherto explored.'
In this manner, and by employing a cause that appears adequate to the effect, and which is know!), even at this time, partially to exist; the Author at once accounts for the fingular appearances which the present earth exhibits on and beneath its fura face, for the general deluge, and for its ceffation; and this he does, without having recourse to comets, a sudden 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 impressions of marine animals have not only, as we have already observed, been found in all parts of the globe; but it is likewise well known that the exuviæ, &c. of shell fish which now inhabit only the seas between the tropics and near the line, have been frequently found here in England, and in various other parts very remote from their present native climates; and sometimes deposited with as much order as beds of living shell fish are in the sea. Thus for instance, the chambered Nautilus, and remains of the Fawkes bill, Loggerhead, and Green Sea Tortoise, of Alligator's teeth, and of various shell fish, that now inhabit the Chinese ocean, or the East and West Indies, have been found at Sheppy island, Richmond in Surry, and different parts of England. Remains, likewise, or impresfions of Crocodiles have been found in Derbyshire, Germany, &c.
Though these remains were deposited in these places at the æra of the deluge, or in consequence of the elevation of the strata, in which they are found, from the bottom of the Antediluvian ocean;
the Author conceives it to be repugnant to common sense to suppose that these bodies could have been translated from their native beds in a distant climate, and brought into their present situation by the waters of the deluge. He cannot admit that regular beds of oysters, &c. for instance, natives of the American seas, could have been removed some thousand miles from their original seats, and deposited here with as much order as is observed in the beds of living thell filh. On the contrary,
he affirms that they are now found in the very fame foot of the globe where they formerly lived and associated : though some of the species do not, or perhaps cannot, exist in the same latitudes, at present. The Author's attempt to folve the difficulty is principally founded on the following observation.
Animals might live, he alleges, in the primitive globe, universally covered with water, which cannot exist in the same parts of the present globe, in consequence of the very great change in the temperature of climates, occasioned by the production of iminense continents and mountains. From a confidera. tion of the different properties of land and water, with respect to the transmitting or conducting of heat, the Author infers that the different regions of the primitive globe enjoyed a more equable temperature than the present, in consequence of the former having been uniformly covered with water, or containing islands of small extent and elevation, and being thereby more extensively adapted both to animal and vegetable life. On similar grounds he accounts for the longevity of our antediluvian forefathers; and still keeping an eye on Mofes, terminates his principal inquiry by a chapter on the postdiluvian rainbow.
In the Appendix to this work are contained several cúrious particulars relative to the different strata of the mines in Derbyfhire, their arrangement, correspondence, dislocations, and the changes they have undergone at different periods of time. These obfervations are illustrated by several plates, representing sections of them, in which their direction, situation, depth, and other circumstances are satisfactorily delineated. From this part of the work we cannot resist the temptation of extracting a few striking particulars.
One of the most remarkable of these strata is that called toadStone, black-ftone, channel, or cat-dirt, as it is variously denominated in different parts of these mining districts. This stratum the Author pronounces to be as much a lava as that which flows from Hecla, Vesuvius, or Ætna.' It is blackish, very hard, and of a close texture ; contains bladder-holes like the scoria of metals, and has the same chemical property of resisting acids. It seems to be the product of a later period than that of the limestone strata which it repeatedly separates; and between which it evidently appears to have flowed, as well as to have filled up the fissures that lay under it. These limestone strata contain various metallic ores, as well as figured ftones exhibiting the impressions of numerous species of marine animals; fome of which are not known to exist in the British seas * :
The impression of a Crocodite likewise was found in' a' ftratum of this stone, in one of the Derbyshire minés, a section of which is given in the firit of the Aushor's plates.
whereas this substance, which is as uniform as any vitrified matter of this kind can be supposed to be, neither contains minerals, nor figured ftones, nor has any adventitious bodies enveloped in it. Neither does it universally prevail, as the limestone Prata; nor is it, like them, equally thick; but in some instances varies in thiekness from six feet to fix hun. dred.'
Another circumstance that seems to prove it a volcanic production is, that a stratum of clay lying under it, has been found in yarious places, exhibiting the appearance of having been burnt, as much as an earthen pot or brick. On a comparison, no sensible difference could be observed between this clay, and another portion of clay in a mine at Heynor common, which had been burnt by a stratum of coal having been on fire underneath it. On this occasion the Author offers some probable conjectures, to explain in what manner this lava was introduced between such immense strata of stone; and why it did not force its way through the surface of the earth, according to the usual course of volcanic operations.
In this Appendix the Author makes a general and important remark, founded on the result of his observations made not only in Derbyfhire, but in Staffordfhire, Shropshire, &c. It relates to the difference of situation between the marine or animal exuvia, and the impreffions of vegetables. The superior or clayey firata, contain the vegetable impressions, but exhibit no marine productions whatever: whereas the inferior or lime stone firata, contain the exuviæ of marine animals, and no vegetable forms whatever. These circumstances, according to him, indicate the order in which the respective firata were fucceflively arranged. The inferior lime stone Arata, containing marine productions only, must bave been constituted while the sea covered the earth: the superior, exhibiting impressions 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 contradi&ts the general order': but thefe he considers only as anomalies, occasioned by partial or local revolutions. In Derbyshire, one instance only seems, at first fight, to contradi& his general rule. Numerous exuvia of thell fith have been found in the superior ftrata, incumbent on lime ftone: but on examination it appears that these shells are not marine productions, but of fresh water lakes, rivers, &c.; in short, they are the remains of horfe muscles.
We cannot terminate our account of this performance without taking notice of a very extraordinary phenomenon, that has frequently been observed in fome of the Derbyshire mines here named; where the vein of ore is divided into two equal paris,
parallel to the sides of a fissure, refembling two slabs of marble, whose surfaces, which have a high natural polish, are in contact with each other, though without the least degree of cohefion. The fingular circumstance relating to them is thus described.
" If a sharp pointed pick is drawn down the veia with a small degree of force, the minerals begin to crackle, as sulphur excited to become electrical by rubbing; after this, in the space of two or three minutes, the solid mass of the minerals explodes with much violence, and the fragments fly out, as if blasted with gun-powder. 1,6 These effects have frequently happened, by which many work. men have been much wounded, but none killed, both in the Eyam mines and in that at Castle:on.
• In the year 1738 a prodigious explosion happened in the mine called Haycliff.
• The quaniity of two hundred barrels of the above minerals were, blown out at one blaft; each barrel, I presume, contained no less than three or four hundred weight.
• At the same time a man was blown twelve fathoms perpendicular, and lodged upon a floor, or bunding, as the miners call it.
• When the above explosion happened, the barrel, or tub, in which the minerals, &c. are raised to the surface, happened to hang over the engine-thaft, 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 considerable weight, was lifted up in the hook on which it was suspended; and the people on the surface felt the ground Make, as by an earthquake.
'Such are the effects which have frequently been produced in all the above mines: but from what cau they proceed I have not yet been able to discover, nor even the least traces towards it.
• When these wonderful effects first happened they deterred the workmen for some years from venturing to work the mines, buc afterwards they availed themselves of this
extraordinary property. A man would go to the forefield, give a scratch with his pick, and run away; by which means he loosened as much of the minerals as could have been done by common workmanship with ten men in three months.
" These curious observations I received from Mr. Mettam of Eyam, . overseer of the mines, who also addressed the following account of them to Mr. George Tislington of Winster.
Eyam, 2 July, 1763. “ I send you, by the bearer, two specimens of our Nickensides, containing all the variety of minerals where the explofions happen ; they fly out in such slappits t, smooth on one side. The explosions are sometimes heard to the surface, and felt like an earthquake; they frequently blow out all the candles in the mine, and fplit the Stemples I into splinters as small as the twigs of a birch beesom, to
* Slickenhdes, shining, as if polished by art, on one side.
I Stemples, joints laid across fiffures, when the minerals are cut out, by way of making a floor, on which rubbish is deposited, to save the expence of railing it to the surface.
the disance of thirty or forty yards from the forefield ; others are broke, and some of them become too short and drop out.
“! The fmooth sides lie face to face, and have the appearance of being shot with a plane, confisting of various members. There is generally two of ihese divisions in our forefield at Haycliff, about cight or ten inches afunder, and a seam 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 ceaseth ; then they run away, knowing that the explofion will follow in a minute or two. Sometimes a noise is heard like the beating of a church clock, after which the greatelt explosions happen.
I am yours, &c. To Mr. George Tiffington,
WILLIAM METTAM." Winster. We shall only add, that on the memorable first of November 1755, about ten in the morning, when the earthquake so fatal to Lisbon happened, the workmen were greatly alarmed in these very mines. The rocks which surrounded them were so much disturbed, that foil, &c. fell from their joints or fiffures; and they likewise heard violent explosions, as it were of cannon. Being thus alarmed, they left their fubterraneous employment, and Hed to the surface for safety.'-On their return, however, they did not observe any material change.
How far the present theory corresponds with all the phenomena we shall not undertake to pronounce: nor should our Readers draw any conclusions from this short abstract of a system, 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 testimonies produced in support of it. A well founded judgment can only be formed after an attentive perusal of the work itself; 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 Bria
tish Nation in Indoftan. Vol. II. Continued : See our last Review. 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 Vandivash: a battle not less interesting or memorable than that of Plalley.
• The distance from Tirimbourg to Vandivalh is seven miles; the road leads from the N. E, to the S. W. The mountain of Vandivash lies in the same direction, extending more than a league in length. The fort stands two miles to the s. of the mountain, but nearer to, the western than the eastern end. The French army was encamped. direatly opposite to the eastern end of the mountain, at the distance