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that our continents are diversified with mountains, hills, and plains, which are formed by beds or firata, and the greatest part of thefe Arata contain marine bodies: to account for this fax, they observe, that as the present rivers diminish gradually our continents, and produce, from their materials, new ones in the sea, there were ancient rivers which demolished the ancient continents, and out of them formed ours. But our Author attacksthis hypothefis, in order to prove the impossibility of the formation of our continents from ancient ones destroyed by the rivers - if such destruction be allowed to have exifted *. To render his refutation clear, and unanswerable, he examines circumstantially the action of running waters upon the continents, and the causes that maintain the latter, and their mountains, against the influence of this action; these causes are not only physical, such as molles, vegetation, &c. for the intervention and labours of men have contributed to the same end. These causes open to our Author a field for sentimental, as well as instructive discussions; for which we must refer the reader to the work itself. They will certainly please both his understanding and his heart.
In the fifth part, our Author considers and refutes the systems, which attribute the formation of our continents to the SLOW CHANGES that have taken place in the level of the sea, Under this title, various hypotheses come into consideration, and engage him in deep and laborious researches. He combats, by the united powers of astronomy, geography, phyfics, and natural history, the system of those, who attribute the revolutions that have happened on the surface of the earth to the changes of its axis. He overturns the hypothesis of M. Le Cat, that was received with such applause in the year 1750. According to this, the earth, in its first state, is supposed to have been a globe, whose constituent parts being ranged according to their specific gravities, was of consequence covered with water; and would have remained eternally in that state, had not the Creator formed the moon, whose attraction formed the tides, while the violence of the tides setting the heavy parts of the earth in motion, produced the continents with their mountains and inequalities, and are imperceptibly mining both at present, to reproduce them again, and to destroy them again. Our Au
This M. De Luc does not believe: he proves, on the contrary, that our continents, by their tendency to undergo fome change, in their form, by the circulation of the waters, tend thereby to their pero fection, instead of being threatened by that cause with the destruction, which some writers have fancied. This is a curious point of natural history, which, though it is not necessary to our Author's argument, furnishes, nevertheleis, a new proof, that our continents are not the cffect of ancient rivers.
thor, whose patience and candour keep an equal pace with his penetration and knowledge, disputes the ground inch by inch with this most unphilosophical hypothesis, and thews its glaring contrariety to the laws of motion, to many of the most invariable laws of nature, and also, to the most undoubted and best ascertained phenomena.
The hypothesis of Telliamed (De Maillet) is the next that receives a mortal blow from our Herculean deliverer of the physical world from monsters and chimeras. He follows this strange author (who makes the sea the parent of all things), and examines his proofs of the diminution of the sea, and his whimlical opinions concerning the system of the universe, the population of the planets, the origin of plants, terrestrial animals, and man, and finishes these discuffions, by shewing the insufficiency of natural history and physics to account for the existence and formation of any living being.
The THIRD VOLUME, in which we find the seventh and eighth parts of the work, contains a relation of two different voyages, made by our Author, into Germany and Holland. The firit, which is the subject of twenty-five letters, exhibits a rich variety of entertainment to the natural historian, and often interesting points of view to the moralif; for few observers blend these two spheres of contemplation together, with such judge ment and sensibility as M. De Luc. Among other things, the reader will find here the first lines of our Author's physical chronolegy, deduced from a view of the earth's surface, and other phenomena, and which we look upon, as infinitely superior in probability to many other methods of computation, which have been deemed respectable. The route of our Author through Lower Saxony, Hanover, Zell, Gottingen, Westphalia, Guelderland, and Over-Yjel, furnishes him, in the heaths of these countries, whether cultivated or uncultivated, abundant matter of observation. But the chain of mountains at Hartz, and the mines of that district, wbich were the principal objects of this journey, lead our Author into details, which are fingularly interesting, as they mingle the pleasures of rural description with the researches of philosophy. The person that can read, without finding his imagination and heart most pleasingly affected, the fixty. second, and several other letters of this volume, must have a mode of perceiving and feeling very different from that of the author of this article. The description of Osterode, in the neighbourhood of Gottingen, is charming; and, even in the narration of those circumstances that a fastidious critic will look upon as trivial, we discover the spirit of a philofophical and sentimental observer; of a man, who, by his good humour and gaiety, must be an excellent companion on a journey. No object escapes him: por does he, through an apprehenfion of
length, suppress any natural reflectiori. This may render his work more voluminous than it otherwise would have been ; but it renders it, at the same time, more entertaining; and these incidental objects and reflections ferve as a refreshment and interlude between profound and serious disquisitions. Our Author's account of the miners of Claus!hal, and, in general, of the mines of Hartz, and the manner of working them, is curious and instructive : and his observation of the primordial and fecondary mountains, the former in the chains of Hartz, and the latter in the Kahlenberg, is a new refutation of the hypotheas of those, who attribute the present form of out continents, and the origin of all their mountains, to the operation of the waters alone. The eighth part contains the second journey of M. DE Luc in Holland and Germany, by a different route, by Helvoet, Grauc, Osnabrug, Hanover, Pyrmont, Munden, Casil, Francfort, Heidelberg, Manheim, Mentz, Coblentz, Cologn, Juliers, Maeftricht, Tongres, and Brussels. The principal things that we meet with here, are certain particularities, and reflections relative to heaths and the soil that they cover, to the mineral waters of Pyrmont, to the vestiges of volcanic erruptions in fome parts of that route, and in the mountain of Caffel, as also, along the borders of the Rhine from Coblentz to Cologn. Several incidental details of a moral and social kind embelli
that which relates the meeting with Peternel Van de Schans, a hospitable goody, is the only one that may be thought am-interesting; and such it will appear to many readers. The ninth part is the largest of all
, and takes up entirely the fourth volume. It contains, in thirty letters, our huthor's third voyage into Holland and Germany; and as, in this voyage, he passed through, nearly, the same places that he had formerly visited, it was not poffible that he hould avoid repetitions. But as these repetitions throw new light upon objects, which had been viewed with more or less rapidity, and deserved to be made farther known, they merit rather the name of illustrations; and, indeed, the points of view presented to our Author, and his observations upon them, in this third voyage, are every way adapted to satisfy a curiosity that was still left in the expeáation and defire of farther information. The principal objects exhibited here, are-A description of the coast of Harwic confidered, with respect to the diminutions or acceffions which it has undergone or received ; and remarks on the concretions that are contained in the soil of that coast-Aa Hydraulic description of Holland -Reflections on the state of the heaths in the low and uncultivated parts of Brabant, and the high and cultivated districts in the neighbourhood of Tongrue (whose environs our Author has examined with the most fingular and laborious attention, and perfectly refuted the ancient tradi.
tion, that the sea formerly came up to its walls).-Moral reasons for examining the formation of the earth.-Farther remarks on the volcanos on the banks of the Rhine, and on the formation of the Basaltes.-Volcanic erruptions in the Schilous mountains along the Rhine, and volcanic foil in regular Itrata between Andernach and the lake of Loch; and a description of the volcanos and volcanic phenomena in the neighbourhood of this lake. --The quarries of Trals, and the volcanos in their environs, (in the road from Nieder-Mennich to Neu Wied*).Rocks filled with marine bodies, though in strata, almost vertical like those of the Schisies.-Continuation of the volcanos, at the back of the natural mountains, on the western side of the Rhine between Andernach and Oberwinter.-Mountains of Bazaltes on the fide of the Rhine, opposite to Oberwinter. -An esl'ay on earthquakes.-Hills of lime-stone near Mentz, that confirm our Author's account of the mechanism of petrifaction, and other matters of a like nature.
The fifth Volume comprehends the tenth and the eleventh parts of this work. The tenth contains the observations made by Our Author, in a fourth Tour in Germany, and on the coasts of the northern ocean. Here the natural historian will follow him with pleasure, in his description of the mountains in the counties of Paderborn and La Lippe, of the heaths of Luneburg and IVinsen, of the duchy of Bremen, and of the cosmological phenomena, which he found at Alteland, near Stade ;-in his descriptions of the Kedinger:noor and Duvelsmoor (which signify the Turberies of Keding and the Devil); in his voyage through Oldenburg, East-Friesland, Delfzyl, Groningen, Friesland, and Holland; as also in his route from Utrecht to Pyrmont, and from Pyrmont to Aix la-Chapelle, by Geismar, Wisoaden, and Coblentz. To all this are subjoined some letters from M. Trosjon to our Author, concerning the ancient volcanos, which lie north-ealt of Coblentz, and the strata of pumice-ftone that are to be seen on the banks of the Rhine and the Morelle; and this Part is terminated by a description of the country and foil between Aix-la-Chapelle and Calais.
From all the observations made in these voyages, M. De Luc has been confirmed in his opinion, that our continents are not of a very ancient date—and that not one of the causes, which are known to act upon, and influence our globe, and which, by
• A: Neu wied, there is a Moravian community, which our Author represents in pleasing colours, oblerving, that it is rather on benevolence of character than on peculiarity of opinion, that the association of the Moravian brethren and tiiters is founded. This is, certainly, the most favourable way of representing the Moravians and we hope, and begin to believe, that it is a true one. APP, Rev. Vol. lxii.
their nature, must have acted upon it formerly, as they do now, could have produced the universal change of land into sea, and fea into land, which has undoubtedly taken place, and of which the vestiges are evident. What then is the extraordinary cause that operated this revolution in the surface of our globe? This question our Author answers in the eleventh and Jaft Part, by producing his hypothesis, the result of a long and laborious ftudy of nature, and for which he has prepared the reader in the preceding volumes.
The facts and conclusions deducible from the observations related in the preceding volumes, may be reduced to the following.
The existence of marine productions in our continents, and even in the summits of mountains, indicates a change in our globe, and suppose a cause that placed them there.
These marine bodies are inclosed in certain substances well known, and entirely distinct from them, which substances furround them perfe&tly, and even sometimes fill their little cavities; and therefore, these substances were in a state of softness or fusion when they inclosed these marine bodies.--The natural arrangement of these substances is in regular parallel beds, of ftrata, often horizontal, always a little inclined, fuch, in a word, as the waters form, when they remove any quantities of matter from one place to another, and such as they alone form :
this arrangement, according to our Author, is due to them. - In these beds the fragments of primordial substances are discovered, and therefore these latter existed as they are before these beds were formed. - The fragments of the primordial subftances, found in these beds, though they appear, by undoubted marks, to have belonged to larger masses, have their angles blunted by friction, and thus appear to have been rolled by the waters that formed these beds ;-and as this operation required time, it was not by sudden shocks or movements, that the waters formed the beds, which contain the fragmenis under confidera. tion. These deposits made by the waters have been raised, one above the other, even so as to form high mountains, whose composition is the same from the summit to the base; therefore the waters that formed them were deep, and a considerable fpace of time was taken up in their formation. These mountains contain also marine substances, throughout, but unequally distributed; and the same inequality is observable in the strata of the plains and hills : fome of theie strata contain almost an equal mixture of marine and earthy substances: others contain few or none of the former : sometimes the shells are of one kind - at other times, of various forts ;– frequently there is a mixture of young, old, entire, and broken, with all the marks of the accidents that happen to them in the ocean, &c. “ Therefore