of Minerals, with Examples of particular Baths. The Generation of Minerals in the Earth, from whence both the actual heat of Baths, and their Virtues proceed. By what Means Mineral Waters are to be difcovered. And laftly, of the Nature and Ufes of Baths, but efpecially of our Baths at Bathe, in Somertetthire," 4to. 1631. Again in 1632, and revifed and corrected by Dr. Guidott in 1669, 8vo.-This is a performance of no ordinary ingenuity, and evinces, for the period, great chemical and mineralogical knowledge. From the preface to the laft mentioned edition, the above particulars are taken.

THOMAS GUIDOTT, M.D.,

mentioned in the preceding account, was defcended from a noble family at Florence. His anceftor, Antonio Guidotti, came to England about the year 1548, and received from King Edward VI. the honour of knighthood. The fubject of the prefent article was born at Lynington, in Hampshire, in 1638, and was educated at Dorchefter grammar-school,from whence he removed to Wadham college, Oxford, in 1656. He there took his degrees in arts, and entered on the ftudy of phyfic, in which faculty he took his bachelor's degree in 1666, with licenfe to practife. The year following he fettled at Bath, where he was greatly encouraged by an eminent phyfician there, Dr. John Maplet, to whom he afterwards dedicated in a very refpectful and grateful manner, his Difcourfe concerning the Antiquity, &c. of Bath, appended to his edition of Dr. Jorden's book abovementioned. But according to Wood, (Athen. Oxon. II. 1101,) Guidott's practice at Bath decaying, occafioned by his impudence, lampooning, and libelling, he left that place in 1679, and retired to London." In 1671 he performed his exercife at Oxford for the degree of doctor of phyfic, but it does not appear that he ever completed it.

Wood, who gives him a very bad moral character, fays that he was a perfon of good parts, well verfed in Greek and Latin, and intelligent in his profellion.

The fame author alfo fays that he had two offers, one to fettle at Copenhagen under Bartholine, and the other of a profefforihip of phytic at Venice, both of which he declined.

. Beides the piece already noticed, he wrote "Some Enquiries into the Nature of the Water of St. Vincent's Rock, near Bristol, and that of Caftle-Cary :". "Account of the Lives and Characters

of the phyficians of Bath, from 1598 to 1676:"-" Obfervationes Hydrostaticæ, Chromaticæ et Mifcellaneæ, uniufcnjufque Balner apud Bathoniam, naturam, proprietatem, and diftinctionem, curatius exliberes," &c. &c.-When he died is not certain, but he was living in 1690.

SILAS TITUS.

This writer, who made the ufurper Cromwell tremble, was born at Bufhy in Hertfordthire. In 1637 he became a Commoner of Christ Church, Oxford, where he continued about three years, and then removed to one of the inns of court; but the great rebellion breaking out, he entered at firft into the parlia mentary fervice and became a captain. When the king's caufe, however, declin ed, and he faw which way the indepen dents were going, Titus adhered to his fovereign, and was with the commiffioners appointed by parliament to his Majefty at Newcastle, and afterwards at Holdenby. The King being feized at that place and carried off by Cornet Joyce, the commiliioners fent him with an exprefs to the parliament in June, 1647, to acquaint them of the affair, for which fervice the parliament gave him fifty pounds to buy a horse. After the death of Charles the Firft, he became groom of the bedchamber to his fucceffor, whom he followed into Scotland, and ferved under him as colonel at the battle of Worcester. Titus had the good luck to escape after that action, and lived retired. In 1657 he printed by stealth at Loudon, a finall tract in quarto, under the name of William Allen, entitled "Killing no Murder;" in which he proved that it was not only lawful, but highly honourable to lay the ufurper. Nay, he went fo far as to advife Cromwell to kill himfelf, "very fairly giving him his choice of hanging, drowning, or piftolling," which frightened Oliver exceedingly, and great pains were taken to find out the real author, but without effect. This fmall piece at its firft coming out was fold for five fhillings, though the ordinary price of fuch tracts was but fixpence.

At the Reftoration, Colonel Titus was elected into parliament for Loftwithiel, in Cornwall. He oppofed the prerogative in 1678, on the occafion of Oates's plot, for which he loft his place at court. The year following he was chofen knight of the fire for the county of Huntingdon, and in that parliament he zealoutly spoke againft the duke of York.

Notwithstanding this he was introduced to that prince when he was James the

Second,

Second, and kiffed his hand. He is faid alio to bare undertaken a work, recomnding the repeal of the Tett and Penal Laws, as the greatest happiness that could befal the nation, and a bulwark againft popery." For this he was fworn in a member of James's Privy Council, and upon the abdication of that monarch, Titus alfo thought proper to abfent himfelf. But foon after the Revolution, he again appeared on the political stage as member of parliament for Ludlow. His election was oppofed, but confirmed by a committee of the Houfe of Commons in 1690. Colonel Titus died at the clofe of the feventeenth century. Belides his tract abovementioned, which is written in a remarkably vigorous ftyle, feveral fpeeches of bis are in print; and he afufted Dr. Perinchief in his History of Charles the First, particularly with refpect to the two laft years of that monarch's eventful life.

theirs.

The object of the prefent Memoir is not to explain, by fuch events, all the caufes of the inequalities of our globe, which are perhaps principally attributable to crystallization, and other circumftances; I conceive, however, I may be able to thow, that the original inequali ties of the earth have not only been greatly modified by the finkings and difruption of its furface, but that many of them have been actually produced, either while the parts were in the act of confolidation, or after they had attained their complete confiftence. Secondary rocks,

date, afford frequent illustrations of this truth.

This was alfo the opinion formed by Dolomieu, when, a few years after having vifited Calabria, he travelled over the Alps. This celebrated geologift has fince frequently mentioned to me in converfation, that he had obferved nothing which more fatisfactorily explained the fantastic forms often affumed by mountains, the unequal inclination of their firata, and the diffimilarity between the angles of great vallies, than the above theory.

In order to form a correct judgment on the prefent fubject, it is neceffary to enter into fome details, and particularly to recall to mind the principal facts which we owe to this enlightened philofopher. It muft, doubtlefs, be difcovered, after an attentive perufal of thefe obfervations, that my pencil has failed to convey an adequate idea of the fubject; if however my feeble efforts can contribute to fix, in the memory, a few important phænoincna, they may not prove wholly ufelefs.

It ought to be premifed, that Dolomieu did not difcover the fmalleft traces of volcanoes in any of the countries which had fuffered by earthquakes. He neither beheld lava, tufa, fcoriæ, nor bitumens of any kind.

Dolomieu obferves, that in the conti-
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nuation

nuation of the base of many primitive mountains in Calabria, there are found fucceffive firata, compofed of quartzy fand, pebbles, white argill, grains of feldfpath, and mica, as if formed by depofition. Thefe ftrata, which have originated from the decompofition of granite, and are intermixed with fhells, and fragments of marine bodies, appear to have been depofited by the fea. Thefe depofitions, at firft horizontal from north to fouth, and with an inclination from eait to weft, have afterwards been feparated, either by the currents of the fea itself, or by fuperior torrents, and have formed that fucceffion of hills, vallies, and plains, which terminate in a low thore. On this moveable batis, is a bed of black or redcoloured argillaceous vegetable earth, from two to five feet in thickness, extremely compact and tenacions, forming a kind of cruft which contributes to give, a finall degree of folidity to the foil. It has been hollowed out by copious rains, into deep furrows, and gorges, which are fometimes fix hundred feet in depth. Their banks are precipitous, and almoft vertical like walls, becaule the fuperior itratum, being bound together by roots, retains the fuper-incumbent foil.

It refults from a general examination, that granite conftitutes the bafe of nearly all Calabria; and that under this apparsently immoveable bafis, is fituated the focus of the earthquakes to which it is fo liable.

Dolomieu, when penking of the -effects produced by the principal fhock of the earthquake which occurred on the 5th of February, 1783, aud only lafted two minutes, defcribes them in the following manner:

I cannot better explain these effects than by fuppofing that feveral cubes formed of fand, moittened, and heaped up by the hand, are placed upon a table, at a little diftance from one another; if we farther fuppofc, that repeated blows are given to the table underneath, while at the fame time it is fhaken violently in a horizontal direction, we may then form fome idea of the different motions with which the earth was agitated on that occalion. Belides thefe tranfient fuccuflions, heaving up and down, and a kind of whirling motion alfo occurred, fo that it was utterly impoffible any edifice could refift their united influence; houfes and even whole villages were levelled in the fame inftant, their foundations appeared as if they had been ejected by the earth which contained theis; and the ftones

which compofed them were broken and thattered in a thousand pieces. The general effect produced upon the argillaceous fandy foil of the plain was, that it acquired an augmentation of dentity by the diminution of its bulk, that declivities were formed where before precipices only exifted, that internal cavities were filled up, &c. The confequence was that, throughout nearly the whole length of the chain, the foil which had been fupported by the granite of the mountains Caulone, Efope, Sagra, and Afpræmonte, glided down the folid nucleus, leaving an opening feveral feet in breadth, and nine or ten iniles in length. Thus whole fields have funk below their former level, without any of the furrounding fpots having experienced a timilar change, and forined in this manner hollow bafons. Other portions of land have affumed an inclined form, while openings and fiffures appear interfecting hillocks and plains in every direction. Almoft at every tiep we met with fuch openings; but it was principally towards the borders of fleep declivities, that the greatest confufion prevailed. Confiderable portions of foil, covered with vines and olive trees, were detached, and thrown down in a single mafs into the hollow of the vallies, deferibing arches of circles, having as radii the height of the declivities; in that cafe, the upper portions on which the trees food, were removed to a confiderable - distance from their former situation, and remained in a vertical position.

"It is proper to remark, that as the foil of the plain did not forma mafs connected together in its parts, it was ill calculated to propagate motion, fo that its inferior portion received more than it cominuni cated to the upper furfaces. Hence it is, that the lower parts have always fallen firit, and gliding away, like fluids, from underneath the bodies fupported by them; thete bodies funk by their own weight.

"When the projectile force communicated was unusually great, the foil was frequently carried over little bills, and transported to a confiderable distance beyoud them. When the opposite fides of a

valley met, they frequently formed a kind of vault, or cradle. But the most common effect was, when the inferior bafe haring given way, the fuperior foil had fallen perpendicularly, and fucceffively in large portions fo as to affume a position fimilar to the fteps of an amphitheatre. The lowest ftep is fometimes three or four hundred feet below its first putition.