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A P P E N D I X
VOLUME the THIRTY-FIRST,
Specimen Historia Naturalis Globi terraquei, &c. Autore Rudolpho
with regard to the formation of islands, the origin of moun,
learned world, for his edition of the posthumous writings of the celebrated Leibnitz. In the present performance, which is dedicated to the Royal Society of London; he hath given the publick a specimen of a molt elaborate work, in which he is engaged, comprehending a general theory of the carth ; by which he intends to account for the present itate of our tera' raqueous globe ; tracing out the several changes it has undergone, for a succession of ages, by earthquakes, the eruption of volcanos, inundations, the draining of marshes, and other circumstances.
The subjects of this specimen are the islands, that have, for some ages past, been formed in the sea, ani the mountains which have been generated on the continent by earthquakes and subterraneous eruptions. To these he hath added an abftracted review of the principal hypothefes, both ancient and • modern, respecting 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 several, with the means of correcting them.
In his first chapter, Mr. Raspe gives a short description of the interiour parts, or composition, of the outward fhell of the APPEND. VOL. XXXI.
earth; treating both of the different materials it is composed of, and of the manner in which they are disposed in separate strata or beds. Among the plates, serving to illustrate this part of the work, is one of an indescript follil; and another presenting the figure of a piece of wood, taken from the mines of Gofar, so crufted over and impregnated with copper, that the fight of it leaves no room to doubt that metals increase by apposition 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 structure of the earth, and, setting aside the effects of the general deluge, have concurred to reduce it to its present state. It is notorious, he observes, that earthquakes, and those subterraneous fires which cause them, have, in a course of ages, generated several mountains on the surface of the earth, and islands in the bosom of the fea. Mr. Raspe indeed is not the firft naturalist, who haih endeavoured to account for the formation of these mountains and illes; but none appear to have investigated this matter so profoundly, or to have considered the historical relation of facts so critically, as our Author. In this enquiry, therefore, it is no wonder, if he hath frequently improved on the observations, or exposed the overfights and mistakes, of preceding wri
We shall mention one or two instances of the latter. The celebrated M. de Buffon, in the first volume of bis Natural History, relates, that on the 16th of June 1628, there arose such a terrible tempest at the Azores, that the island of St. Michacl opened near the fea, and threw up such 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 Mandleslo's Voyages; and indeed this anecdote is to be found in the French translation of them, publilhed by Wicquefort in 1678. It is also inserted in the English tranflation, published in Harris's collection, in 1705. Mr. Raspe obferves, notwithstanding, that there is all the reason in the world to suppose it a fabulous interpolation, as it is not to be met with in the German edition of his works, printed at Sleswick in 1658, with notes by Olearius; nor in the Low-dutch translation wbich was made of the same work. He remarks also farther that Herbert, who gave a description of the Azores in 1628, speaks not a word of this pretended island; which is supposed to have been thrown up the same year.
Again, Mr. de Buffon falls into an errour with regard to a fact related by Piiny; which our Author takes more than ordiAary pains to expole. Pliny,” says Mr. de Buffon, “relates that there formerly arose, in the Mediterranean sea, thirteen new islands, at one time; of which new islands Rhodes and Delos were the principal. It appears however to me,” contipues Mr. de Buffon, “ both from what Pliny himself advances, and what Ammianus Marcellinus, Philo, and others say on the fame subject, that these thirteen islands were not produced by any earthquake or subterraneous explosion : but most probably existed before, tho' covered by the sea, which at that time subfided and left them.” Mr. Raspe observes, with regard to this suggestion of Mr. dc Buffon, that, in the first place, Pliny does not assert that these thirteen isles, he speaks of, arose out of the sea at one and the same time, nor makes any mention of the sea subfiding at the time of their discovery. Secondly that what is advanced by Ammianus Marcellinus is directly contrary to what Mr. de Buffon supposes he has said. And, as to Philo, that he makes only a general conclusion, that the subfiding, or the diminution of the waters of the fea, was looked upon as a probable opinion by some of the ancients.
Our Author displays no less attention and fagacity in exporing the mistakes of other writers on the subjects he treats : refuting in particular, Cluvier, Walguarnera, and others, in many things they advance relative to the present state of Sicily. Mr. Raspe is of opinion, that the isle of Sicily was formerly united, by an isthmus, to Italy, from which it was separated by an earthquake. He conje&tures farther, on the credit of two palfages to this purpose from Strabo, that it was at first totally immersed by the sea, and was afterwards raised above its surface by the agitations and explofions of Mount Ætna. Extraordinary as this latter supposition may appear at first view, the reasons our Author gives for it are sufficiently plausible to justify a theorist in hazarding it, were it still more problematical. · The result of our Author's researches and criticisms on this head is as follows: that, in the first place, the fact of new inands being generated in the sea, and mountains formed on land, is indisputably authenticated by historians ; that secondly, these ifles and mountains are formed by the various matter thrown up from the bowels of the earth, and not of cinders, stones and minerals, accumulated and exploded by volcanos. And lastly, that such accidents have happened almost every where, in places Jubject to fubterraneous conflagrations and earthquakes.
It is on the supposed certainty of thee facts that Mr. Rafpe proceeds to enquire how far they may reasonably serye in giv; Ii2
ing us a juft idea of the present state of our globe, with regard to the composition of its surface: To this end, he enters in his third chapter, into a previous examination of the principal fyrtems that have been broached on the subject; rejecting, however, all such imaginary hypotheses, as depend on the mechanism of the earth merely by supposition; as also, all plastic forms, equivocal generations, and other chimeras of the fame nature. He rejects, in like manner, all those philosophical theories of the earth, which appear too refined and complicated to accord with that simplicity of action and design, observable in the general system of nature. Hence those of Woodward, Burnet, Whiston, the pretended Telliamed, and even the more recent one of Mr. Lulofs, seem to him altogether unsatisfactory. The learned Reader will see that the opinion on which he founds his own system is the ancient one of Xanthus the Lydian, long fince adopted also by Strabo, viz. that the bed of the sea, which is very unequal, has been from time to time raised and depresfed by earthquakes ; and that it is to this cause we may impute the feveral remarkable changes which have happened on the surface of the globe ; particularly that immense number of fhells and fossils, which are found in the bowels even of the highest mountains. · This opinion of Xanthus, thrown out at first as a mere conjecture, was almost forgotten among the Naturalists, 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, subsided by degrees; the dry land firft appearing in the places adjacent to that where the first 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 universally distributed by the waters of the sea : and that when its bottom was raised up by the earthquakes, that accompanied the general deluge and formed the mountains, whole beds of such shells were thrown up with it.
This hypothesis of Mr. Ray was adopted, at least in part, by the Abbé Moro, an Italian Naturalist, in a work published at Venice about four and twenty years ago, entitled De Crostacei et degli alteri marini corpiche si trovano su monti. According to this writer, both the earth in general, and its mountains in particular, arose originally from beneath the sea. At first, he says, they contained neither strata of theils nor any organised fosils ; but that subterraneous conflagrations, earthquakes, and volcanos have first thrown up these substances in confused heaps into the waters; wherein they have succesiively subsided, according to their different specific gravity, thereby necessarily disposing themselves in different strata. At the same time, he supposes these eruptions to have ingulphed marine plants and animals of every kind; which subfided in like manner, and thus formed new mountains and new beds of stones, fand, metals and minerals, intermixed with plants and animals; all which remained under the sea, till some new agitation threw them up above its surface. Mr. de Buffon, indeed, hath given this hypothesis a different
In fuppofing that the earth was for a long time immersed under water, he conceives that the substance of our dry land was there compounded of various strata of fossils, &c. and dirposed 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 carthquakes or subterraneous eruptions, but to the violence and perturbation of the waves of the sea. As to those chains of high mountains, which run across Europe, Africa and Afia, from west to eat, and in America from north to south ; Mr. de Buffon considers them as the accumulated sediment of the waters, gradually increased by the flux and reflux of the tide. The formation of the other mountains, which are less, and whose position is more diversified, he imputes to the irregular agitation of winds and currents. With regard to the method in which he conceives the land and water became so distinctly separated as it is at present; this celebrated Naturalist thinks it might be in a great mcafure effected by the retreat of the water into certain vast caverns beneath, into which it might be precipitated from its own weight, and thus leave a great part of the surface 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 absurd to suppose the existence of such immense caverns as would swallow up so much water as was necessary to leave dry moun. tains upward of twelve thousand feet above the surface of the sea* ; and such are to be found both in the old world and the new. Add to this, continues Mr. Raspe, that neither the actual conformation of the mountains, with their different inclinations of strata, nor the regular figure of the hills, with their correspondent angles, are at all explicable by Mr. de Buf
It has been generally supposed by Naturalists, that the surface of the sea is remarkably lower than it was formerly. Mr. Raspe, howe. yer, doubts the fact, on the credit of Donati, who in his Essay on the Natural History of the Adriatic, insists, on the contrary, that it is higher than it was in ancient times, at lealt in some places,