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Specimen Hiftoria Naturalis Globi terraquei, &c. Autore Rudolpho Erico Rafpe.

A Specimen of a Natural History of the Earth; particularly with regard to the formation of islands, the origin of mountains, and the phenomena of petrified bodies. Illuftrated with plates. 8vo. Printed at Leipzig, 1763.


HE judicious Author of this effay, is well known to the learned world, for his edition of the pofthumous writings of the celebrated Leibnitz. In the prefent performance, which is dedicated to the Royal Society of London, he hath given the publick a specimen of a moft elaborate work, in which he is engaged, comprehending a general theory of the earth; by which he intends to account for the prefent ftate of our ter raqueous globe; tracing out the feveral changes it has undergone, for a fucceffion of ages, by earthquakes, the eruption of volcanos, inundations, the draining of marthes, and other circumftances.

The fubjects of this fpecimen are the islands, that have, for fome ages paft, been formed in the fea, and the mountains which have been generated on the continent by earthquakes and fubterraneous eruptions. To these he hath added an abftracted review of the principal hypothefes, both ancient and modern, refpecting the exteriour structure of the globe; prefer ring that of our learned countryman, Dr. Hooke, to all others. Not that he thinks the Doctor's theory entirely free from defects: for he hath pointed out feveral, with the means of correcting them.

In his first chapter, Mr. Rafpe gives a fhort defcription of the interiour parts, or compofition, of the outward fhell of the APPEND. VOL. XXXI. I i


earth; treating both of the different materials it is compofed of, and of the manner in which they are difpofed in separate strata or beds. Among the plates, ferving to illuftrate this part of the work, is one of an indefcript foffil; and another prefenting the figure of a piece of wood, taken from the mines of Goflar, fo crufted over and impregnated with copper, that the fight of it leaves no room to doubt that metals increase by appofition of parts, in the veins and cavities of the mountains, independent of the large beds of them that are found in greater depths.

Having given a general sketch of his theory, our ingenious Author proceeds next to animadvert on those accidents which have contributed to change the original ftructure of the earth, and, fetting afide the effects of the general deluge, have concurred to reduce it to its prefent state. It is notorious, he obferves, that earthquakes, and thofe fubterraneous fires which cause them, have, in a courfe of ages, generated feveral mountains on the furface of the earth, and iflands in the bofom of the fea. Mr. Rafpe indeed is not the firft naturalift, who hath endeavoured to account for the formation of thefe mountains and isles; but none appear to have inveftigated this matter fo profoundly, or to have confidered the hiftorical relation of facts fo critically, as our Author. In this enquiry, therefore, it is no wonder, if he hath frequently improved on the obfervations, or exposed the overfights and miftakes, of preceding writers. We fhall mention one or two inftances of the latter. The celebrated M. de Buffon, in the first volume of his Natural Hiftory, relates, that on the 16th of June 1628, there arose fuch a terrible tempeft at the Azores, that the island of St. Michael opened near the fea, and threw up fuch a quantity of matter, out of the bowels of the earth, as formed an island a league and a half in length, and above fixty fathom high, on the very fpot where before was an hundred and fifty fathom water. For the truth of this extraordinary fact, Mr. de Buffon quotes Mandleflo's Voyages; and indeed this anecdote is to be found in the French tranflation of them, published by Wicquefort in 1678. It is alfo inferted in the English tranfla tion, publifhed in Harris's collection, in 1705. Mr. Rafpe obferves, notwithstanding, that there is all the reafon in the world to fuppofe it a fabulous interpolation, as it is not to be met with in the German edition of his works, printed at Slefwick in 1658, with notes by Olearius; nor in the Low-dutch tranflation which was made of the fame work. He remarks alfo farther that Herbert, who gave a defcription of the Azores in 1628, fpeaks not a word of this pretended island; which is fuppofed to have been thrown up the fame year.

Again, Mr. de Buffon falls into an errour with regard to a fact related by Pliny; which our Author takes more than ordinary pains to expose. "Pliny," fays Mr. de Buffon,"relates that there formerly arofe, in the Mediterranean fea, thirteen new islands, at one time; of which new islands Rhodes and Delos were the principal. It appears however to me," conti nues Mr. de Buffon, "both from what Pliny himself advances, and what Ammianus Marcellinus, Philo, and others fay on the fame subject, that these thirteen islands were not produced by any earthquake or fubterraneous explosion: but most probably exifted before, tho' covered by the fea, which at that time fub fided and left them." Mr. Rafpe obferves, with regard to this fuggeftion of Mr. de Buffon, that, in the first place, Pliny does not affert that these thirteen ifles, he speaks of, arofe out of the fea at one and the fame time, nor makes any mention of the fea fubfiding at the time of their difcovery. Secondly that what is advanced by Ammianus Marcellinus is directly contrary to what Mr. de Buffon fuppofes he has faid. And, as to Philo, that he makes only a general conclufion, that the fubfiding, or the diminution of the waters of the fea, was looked upon as a probable opinion by fome of the ancients.

Our Author displays no lefs attention and fagacity in expofing the mistakes of other writers on the fubjects he treats: refuting in particular, Cluvier, Walguarnera, and others, in many things they advance relative to the prefent ftate of Sicily. Mr. Rafpe is of opinion, that the isle of Sicily was formerly united, by an ifthmus, to Italy, from which it was feparated by an earthquake. He conjectures farther, on the credit of two paffages to this purpose from Strabo, that it was at firft totally immerfed by the fea, and was afterwards raifed above its furface by the agitations and explofions of Mount Etna. Extraordinary as this latter fuppofition may appear at first view, the reasons our Author gives for it are fufficiently plaufible to justify a theorift in hazarding it, were it ftill more problematical.


The refult of our Author's refearches and criticisms on this head is as follows: that, in the first place, the fact of new ilands being generated in the fea, and mountains formed on land, is indifputably authenticated by hiftorians; that fecondly, thefe ifles and mountains are formed by the various matter thrown up from the bowels of the earth, and not of cinders, ftones and minerals, accumulated and exploded by volcanos. And lastly, that fuch accidents have happened almost every where, in places fubject to fubterraneous conflagrations and earthquakes.

It is on the fuppofed certainty of thefe facts that Mr. Rafpe proceeds to enquire how far they may reasonably ferve in givI i 2


ing us a juft idea of the prefent ftate of our globe, with regard to the compofition of its furface: To this end, he enters in his third chapter, into a previous examination of the principal systems that have been broached on the fubject; rejecting, however, all fuch imaginary hypothefes, as depend on the mechanifm of the earth merely by fuppofition; as also, all plastic forms, equivocal generations, and other chimeras of the fame nature. He rejects, in like manner, all those philofophical theories of the earth, which appear too refined and complicated to accord with that fimplicity of action and defign, obfervable in the general fyftem of nature. Hence thofe of Woodward, Burnet, Whifton, the pretended Telliamed, and even the more recent one of Mr. Lulofs, seem to him altogether unfatisfactory. The learned Reader will fee that the opinion on which he founds his own fyftem is the ancient one of Xanthus the Lydian, long fince adopted alfo by Strabo, viz. that the bed of the fea, which is very unequal, has been from time to time raised and depreffed by earthquakes; and that it is to this caufe we may impute the feveral remarkable changes which have happened on the furface of the globe; particularly that immenfe number of shells and foffils, which are found in the bowels even of the highest mountains. This opinion of Xanthus, thrown out at first as a mere conjecture, was almoft forgotten among the Naturalifts, till our countryman, Ray, revived it, toward the latter end of the last century.

Mr. Ray conceived that the waters, by which the earth was originally overflown, fubfided by degrees; the dry land first appearing in the places adjacent to that where the firft man and animals were placed at the creation: that it extended itself by degrees; a confiderable time elapfing before the waters had returned into their proper beds; during which time the shell-fish, multiplying in great abundance, were univerfally diftributed by the waters of the fea: and that when its bottom was raised up by the earthquakes, that accompanied the general deluge and formed the mountains, whole beds of fuch fhells were thrown up with it.

This hypothefis of Mr. Ray was adopted, at leaft in part, by the Abbé Moro, an Italian Naturalift, in a work published at Venice about four and twenty years ago, entitled De Croftacei et degli altri marini corpiche fi trovano fu monti. According to this writer, both the earth in general, and its mountains in particular, arofe originally from beneath the fea. At first, he fays, they contained neither ftrata of fhells nor any organised foffils; but that fubterraneous conflagrations, earthquakes, and volcanos have first thrown up thefe fubftances in confused heaps into the waters; wherein they have fucceffively fubfided, according to

their different fpecific gravity, thereby neceffarily difpofing themselves in different ftrata. At the fame time, he fuppofes these eruptions to have ingulphed marine plants and animals of every kind, which fubfided in like manner, and thus formed new mountains and new beds of ftones, fand, metals and minerals, intermixed with plants and animals; all which remained under the fea, till fome new agitation threw them up above its furface.

Mr. de Buffon, indeed, hath given this hypothefis a different turn. In fuppofing that the earth was for a long time immerfed under water, he conceives that the fubftance of our dry land was there compounded of various ftrata of foffils, &c. and difposed into horizontal and parallel directions by the uniform motion of the waters. He imagines that the mountains do not owe their origin to the violence of earthquakes or fubterraneous eruptions, but to the violence and perturbation of the waves of the fea. As to those chains of high mountains, which run across Europe, Africa and Afia, from weft to east, and in America from north to fouth; Mr. de Buffon confiders them as the accumulated fediment of the waters, gradually increased by the flux and reflux of the tide. The formation of the other mountains, which are lefs, and whofe pofition is more diverfified, he imputes to the irregular agitation of winds and currents. With regard to the method in which he conceives the land and water became fo diftinctly feparated as it is at prefent; this celebrated. Naturalift thinks it might be in a great measure effected by the retreat of the water into certain vaft caverns beneath, into which it might be precipitated from its own weight, and thus leave a great part of the furface it before occupied, entirely dry.

This fuppofition of Mr. de Buffon, is embraced, with some little variation, by the celebrated Hollman of Gottingen. Our Author, however, can by no means admit of it; thinking it abfurd to fuppofe the existence of fuch immenfe caverns as would Iwallow up so much water as was neceffary to leave dry mountains upward of twelve thousand feet above the furface of the fea* and such are to be found both in the old world and the new. Add to this, continues Mr. Rafpe, that neither the actual conformation of the mountains, with their different inelinations of ftrata, nor the regular figure of the hills, with their correspondent angles, are at all explicable by Mr. de Buf

It has been generally fuppofed by Naturalifts, that the furface of the fea is remarkably lower than it was formerly. Mr. Rafpe, howe. ver, doubts the fact, on the credit of Donati, who in his Essay on the Natural History of the Adriatic, infifts, on the contrary, that it is higher than it was in ancient times, at least in fome places.



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