Chapter VI: Part 6

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“The precession of 50″ yearly has been supposed, this being the result of the comparison of the catalogue of Hipparchus with the modern catalogues. We have thus the advantage of round numbers, and a general accuracy that may be relied upon. The entire period is thus 25,920 years; the semiperiod, 12,960 years; the quarter period, 6480 years; the twelfth, or a sign, 2160 years.

“It is to be remarked, that the constellations leave empty spaces between them, and that sometimes they encroach upon each other. Thus, between the last star of Scorpio, and the first of Sagittarius, there is an interval of 6⅔ degrees. On the other hand, the last of Capricorn is more advanced by 14° in longitude, than the first of Aquarius. Hence, even independently of the inequality of the sun’s motion, the constellations would afford a very unequal and very erroneous measure of the year and its months. The signs of 30° furnish a more convenient and less defective one. But the signs are merely a geometrical conception; they can neither be distinguished nor observed; and they are continually changing place from the retrogradation of the equinoxial point.

“We have at all times been able to determine, in a rough manner, the equinoxes and solstices; at the long run it has been remarked, that the appearance of the heavens was no longer exactly the same that it anciently was at the times of the equinoxes and solstices. But we have never been able to observe exactly the heliacal rising of a star, being always necessarily some days wide of it; and people frequently speak of it, without possessing a fixed datum on which to count. Before Hipparchus, we find nothing, either in books or in traditions, that can be submitted to calculation; and it is this which has given rise to so many systems. Controversies have arisen without a sufficient knowledge of the subject. Those who are not astronomers may form ideas as beautiful as they please of the knowledge of the Chaldeans, Egyptians, &c.; no real inconvenience will result. The enterprise and knowledge of the moderns may be lent to these nations, but nothing can be borrowed from them; for they have either had nothing, or they have left nothing. Astronomers will never derive from the ancients any thing that can be of the slightest utility. Let us leave to the learned their vain conjectures, and confess our utter ignorance respecting things of little use in themselves, and of which no monument remains.

“The limits of the constellations vary according to the authors which we consult. We find these limits extend or contract, as we pass from Hipparchus to Tycho, from Tycho to Hevelius, from Hevelius to Flamstead, Lacaille, Bradley, or Piazzi.

“I have said elsewhere, the constellations are good for nothing, unless at the most to enable us to mark the stars with more ease; whereas the stars in particular afford fixed points to which we can refer the motions, whether of the colures or of the planets. Astronomy commenced only at the period when Hipparchus made the first catalogue of the stars, measured the revolution of the sun, that of the moon, and their principal inequalities. The rest presents nothing but darkness, uncertainty, and gross error. The time would be lost that were occupied in attempting to reduce this chaos to order.

“I have given, with the exception of a few particulars, the whole of my opinion on this subject. I am nowise anxious about making converts, for it gives me little concern whether my ideas be adopted or not; but, if my reasons be compared with the reveries of Newton, Herschell, Bailly, and so many others, it is not impossible but that, in time, these more or less brilliant chimeras will no longer be relished.

“I have attempted to determine the extent of the constellations, according to the catasterisms of Eratosthenes; but the thing is really impossible. The matter would be still worse were we to consult Hygin, and especially Firmicus. The following is what I have made out from Eratosthenes.

CONSTELLATIONS. DURATIONS.
Years.
Aries, 1747
Taurus, 1826
Gemini, 1636
Cancer, 1204
Leo, 2617
Virgo, 3307
The Talons, 1089[219]
Scorpio, 1823
Sagittarius, 2138
Capricorn, 1416
Aquarius, 1196
Pisces, 2936

“As to the Chaldeans, Egyptians, Chinese, and Indians, there is no want of reveries among them. One can absolutely make nothing of them. My opinion with regard to them may be seen in the preliminary discourse of my History of the Astronomy of the Middle Age, p. xvii and xviii. See also the note affixed to the Report on the Memoirs of M. de Paravey, vol. viii. of the Nouvelles Annales des Voyages, and republished by M. de Paravey in his Summary of his Memoirs upon the Origin of the Sphere, p. 24, 31-36. See further the Analysis of the Mathematical Labours of the Academy in 1820, p. 78 and 79.

“DELAMBRE.”

* * * * *

It would still have to be ascertained at what period the observers ceased to place the constellation in which the sun entered after the solstice, at the head of the descending signs, and whether this was done as soon as the solstice had retrograded sufficiently to touch the preceding constellation.

Thus MM. Jollois and Devilliers,--to whose unremitting zeal we are indebted for an accurate knowledge of these famous monuments, always considering the division towards the entrance of the porch as the solstice, and judging that the Virgin must have been regarded as the first of the descending constellations, insomuch as the solstice had not receded at least so far as the middle of the constellation of the Lion; and, believing that they saw farther, as we have mentioned, that the Lion is divided in the great zodiac of Esne, have not given to that zodiac a more remote antiquity than 2160 years before Christ.[220]

Mr Hamilton, who was the first that observed this division of the sign of the Lion, in the zodiac of Esne, reduced the distance of the period at which the solstice occurred there, to 1400 years before Christ. A great many other opinions have appeared on the same subject. M. Rhode, for example, has proposed two. The first refers the zodiac of the portico of Dendera to a period of 591 years before Christ; the second, to 1290[221]. M. Latreille has fixed the period of this zodiac at 670 years before Christ; that of the planisphere at 550; that of the zodiac of the great temple of Esne at 2550; and that of the small one at 1760.

But a difficulty inherent in all the dates, which proceed on the double supposition, that the division marks the solstice, and that the position of the solstice marks the epoch of the monument, is the unavoidable consequence that the zodiac of Esne must have been at least 2000, and perhaps 3000, years[222] older than that of Dendera, a consequence which evidently involves the supposition in ruin; for no one, in any degree acquainted with the history of the arts, could believe, that two edifices, so similar in their style of architecture, could have been erected at periods so remote from each other.

The feeling of this impossibility, joined always to the belief that this division of the zodiacs indicates a date, has given rise to another conjecture, namely, that the intention had been to mark the particular sacred year of the Egyptians, in which the monument had been erected. As these sacred years consisted only of 365 days, if the sun, at the commencement of one occupied the commencement of a constellation, he would be nearly six hours later in returning to the commencement of the following year, and, after 121 years, he would only be at the commencement of the preceding sign. It seems natural enough that the builders of a temple might wish to indicate about what period of the great, or Sothian year, it had been erected; and the indications of the sign, by which the sacred year then commenced, was a good enough means. It will be perceived, that, calculating upon this assumption, there will be an interval of from 120 to 150 years between the temple of Esne and that of Dendera. But, in his mode of solving the problem, there remained to be determined in which of the great years these buildings had been erected, whether in that which ended in the year 138 after, or in that which ended in 1322 before Christ, or in some other.

The late Visconti, who was the first author of this hypothesis, taking the sacred year, whose commencement corresponded with the sign of the Lion, and judging from the resemblance of the signs, that they had been represented at a period when the opinions of the Greeks were not unknown to the Egyptians, was naturally led to make choice of the end of the last great year, or the space that elapsed between the year 12 and the year 138 after Christ[223], which appeared to him to accord with the Greek inscription, of which, however, he knew little more than that it was said to make mention of one of the Cæsars.

M. Testa, seeking the date of the monument in another order of ideas, went so far as to suppose that since the Virgin is seen at Esne, at the head of the zodiac, it was meant thereby to represent the era of the battle of Actium, such as it had been established with regard to Egypt, by a decree of the senate, mentioned by Dion Cassius, and which commenced in the month of September, the day on which Alexandria was taken by Augustus.[224]

M. de Paravey considered these zodiacs in a new point of view, which embraced at once both the revolution of the equinoxes, and that of the great year. Supposing that the circular planisphere of Dendera must have been set to the east, and that the axis from north to south is the line of the solstices, he found the summer solstice at the second of the Twins, and that of winter at the buttock of the Sagittary, while the line of the equinoxes would have passed through the Fishes and the Virgin, from which he obtained for date the first century of our era.

According to this method, the division of the zodiac of the portico could no longer refer to the colures, and the mark of the solstice must be sought for elsewhere. M. de Paravey having remarked that there are between all the signs figures of women bearing a star upon their heads, and marching in the same direction, and observing that the one which comes after the twins, is alone turned in a direction contrary to the others, judged that it indicates the _conversion_ of the sun or the tropic, and that this zodiac corresponds in this way with the planisphere.

By applying the idea of easting to the small zodiac of Esne, the solstices would be found between the Twins and the Bull, and between the Scorpion and Sagittary; they would even be marked by the change of direction of the Bull, and by the winged Rams placed across at these two places. In the great zodiac of the same city, the marks would be the cross position of the Bull, and the reversed one of the Sagittary. There would thus be but a portion of a constellation traversed between the dates of Esne and those of Dendera, but even this would be still too long for buildings so closely resembling each other.

An operation of the late M. Delambre upon the circular planisphere appears to confirm these conjectures, detracting from its remote antiquity; for, on placing the stars upon Hipparchus’s projection, according to the theory of that astronomer, and according to the positions which he has given them in his catalogue; and augmenting all the longitudes, so that the solstice might pass through the second of the Twins, he nearly reproduced this planisphere; and “the resemblance,” says he, “would have been still greater, had the longitudes been adopted such as they are in the catalogue of Ptolemy, for the year 123 of our era. On the contrary, by referring to twenty-five or twenty-six centuries back, the right ascensions and the declinations will be considerably changed, and the projection will assume quite a different figure[225]. All our calculations,” adds this great astronomer, “lead us to this conclusion, that the sculptures are posterior to the epoch of Alexander.”

In reality, the circular planisphere having been brought to Paris by the care of MM. Saunier and Lelorrain, M. Biot, in a work founded upon precise measurements and calculations full of ingenuity, has determined that it represents, according to an exact geometrical projection, the state of the heavens, such as it was 700 years before Christ; but he by no means concludes that it had been sculptured at that period[226].

In fact, all these efforts of intellect and science, in so far as they concern the epoch of the monuments, have become superfluous, since finishing where they should naturally have begun, if the first observers had not been blinded by prejudice, people have taken the trouble of copying and restoring the Greek inscriptions engraved upon these monuments, and especially since M. Champollion has discovered the method of decyphering those which are expressed in hieroglyphics.

It is now certain, and the Greek inscriptions agree with the hieroglyphical inscriptions in proving it, it is certain, we say, that the temples in which zodiacs have been sculptured, were built during the time when Egypt was subject to the Romans. The portico of the temple of Dendera, according to the Greek inscription of its frontispiece, is consecrated to the safety of Tiberius[227]. On the planisphere of the same temple we read the title of _Autocrator_ in hieroglyphical characters[228]; and it is probable that it refers to Nero. The small temple of Esne, that of which the origin has been placed on the lowest calculation between 2700 and 3000 years before Christ, has a column sculptured and painted in the sixth year of Antonine, 147 years after Christ, and it is painted and sculptured in the same style as the zodiac which is near it[229].

Further, we have a proof that this division of the zodiac, in such or such sign, has no reference to the precession of the equinoxes, or to the displacement of the solstice. A mummy case, lately brought from Thebes by M. Caillaud, and containing, according to the very legible Greek inscription upon it, the body of a young man who died in the ninth year of Trajan, 116 years after Christ[230], presents a zodiac divided at the same point as those of Dendera[231]; and all the appearances indicate that this division marks some astrological theme relative to the individual, a conclusion which may probably be equally applied to the division of the zodiacs contained in the temples. It may mark either the astrological theme of the time of their erection, or that of the prince to whose safety they had been consecrated, or such another epoch with relation to which the position of the sun would have appeared of importance to be noticed.

Thus are dissipated for ever the conclusions which people had drawn from some ill explained monuments, against the newness of the continents and nations; and we might have dispensed with treating of them so much in detail had they not been so recent, and had they not made sufficient impression still to retain their influence over the minds of some individuals.

_The Zodiac is far from bearing in itself a certain and excessively remote date._

But there are writers who have maintained that the zodiac bears in itself the date of its invention, because the names and figures given to its constellations are an index of the position of the colures at the time when it was invented; and this date, according to several, is so evident and so remote, that it is quite a matter of indifference whether the representations which we possess of this circle are more or less ancient.

They do not attend to the circumstance that, in this sort of argument, there is a complication of three suppositions equally uncertain: the country in which the zodiac is presumed to have been invented, the signification which is supposed to have been given to the constellations which occupy it, and the position in which the colures were with relation to each constellation, when this signification was attributed to it. According as other allegories have been imagined, or as these allegories are admitted to have referred to the constellation of which the sun occupied the first degrees, or to that of which it occupied the middle, or to that into which it began to enter, that is to say, of which it occupied the last degrees; or, lastly, to that which was opposite to him, and which rose at night; or according as the invention of these allegories is placed in a different climate, must the date of the zodiac also be changed. The possible variations in this respect might comprehend so much as the half of the revolution of the fixed stars, that is to say, 13,000 years, and even more.

In this manner Pluche, generalizing some indications of the ancients, has imagined, that the Ram announces the commencement of the sun’s elevation, and the vernal equinox; that the Cancer indicates his retrogradation to the summer solstice; that the Balance, the sign of equality, marks the autumnal equinox[232]; and that the Capricorn, a climbing animal, indicates the winter solstice, after which the sun returns to us. According to this method, by placing the inventors of the zodiac in a temperate climate, we should have rains under Aquarius, the dropping of lambs and kids under the Gemini, violent heats under the Lion, gathering of the harvest under the Virgin, the time of hunting under the Sagittary, &c.; and the emblems would be appropriate enough. If we should then place the colures at the commencement of the constellations, or at least the equinox at the first stars of Aries, we should, in the first instance, arrive at a period of only 389 years before Christ, an epoch evidently too modern, and which would render it necessary to recur to a complete equinoxial period, or 26,000 years. But if the equinox be supposed to pass through the middle of the constellation, a period of about 1000 or 1200 years higher is obtained, 1600 or 1700 years before Christ; and this is what several celebrated men have believed to be the true epoch of the invention of the zodiac, the honour of which they have, for other reasons not sufficiently weighty, conferred upon Chiron.

But Dupuis, who required for the origin which he endeavoured to attribute to all religions, that astronomy, and, in particular, the figures of the zodiac should in some measure have preceded all other human institutions, has sought another climate for the purpose of finding other explanations for the emblems, and for that of deducing another epoch from them. If, assuming the Balance as an equinoxial sign, but supposing it at the vernal equinox, it be presumed that the zodiac has been invented in Egypt, other sufficiently plausible explanations might in fact be found for the climate of that country.[233] The Capricorn, an animal with the tail of a fish, would mark the commencement of the rise of the Nile at the summer solstice; the Aquarius and Fishes, the progress and diminution of the inundation; the Bull, the time of labouring; the Virgin, the time of reaping; and they would mark them at the periods when these operations actually took place. In this system, the zodiac would have 15,000 years[234] for a sun supposed at the first degree of each sign, more than 16,000 for the middle, and 4000 only, on supposing that the emblem has been given to the sign at the opposite of which the sun was[235]. It is to the 15,000 years that Dupuis has attached himself; and it is upon this date that he has founded the whole system of his celebrated work.

There are not wanting those, however, who, admitting that the zodiac has been invented in Egypt, have imagined allegories applicable to later times. Thus, according to Mr Hamilton, the Virgin would represent the land of Egypt when not yet fecundated by the inundation; the Lion, the season when that country is most liable to be overrun by ferocious animals, and so on[236].

The high antiquity of 15,000 years would besides induce this absurd consequence, that the Egyptians, those men who represented every thing by emblems, and who must have attached a great importance to the circumstance that these emblems were conformable to the ideas which they were intended to represent, had preserved the signs of the zodiac thousands of years after they no longer in any way corresponded with their original signification.

The late M. Remi Raige endeavoured to support the opinion of Dupuis by an argument of an entirely new kind[237]. Having remarked that significations more or less analogous to the figures of the signs of the zodiac, might be found for the Egyptian names of the months, on explaining them by the oriental languages, and finding in Ptolemy that _epifi_, which signifies _capricorn_, commences at the 20th of June, and therefore comes immediately after the summer solstice, he concluded from thence, that, at the beginning, Capricorn itself was at the summer solstice, and so of the other signs, as Dupuis had supposed.

But, independently of all that there is merely conjectural in these etymologies, Raige did not perceive that it was simply by chance that, five years after the battle of Actium, in the year 25 before Christ, at the establishment of the fixed year of Alexandria, the first day of _Thoth_ was found to correspond with the 29th of the Julian August, and continued to correspond since that time. It is only from this epoch that the Egyptian months commenced at fixed days of the Julian year, and only at Alexandria: even Ptolemy did not the less continue to employ in his Almagest the ancient Egyptian year with its vague months[238].

Why might not the names of the signs have been given to the months at some epoch, or the names of the months to the signs, in the same arbitrary manner in which the Indians have given to their twenty-seven months twelve names, selected from among those of their lunar houses, for reasons which it is impossible at the present day to determine[239]? The absurdity which there would have been in preserving for the constellations, during 15,000 years, figures and symbolical names which no longer presented any relation with their position, would have been more evident had it been carried so far as to preserve to the months those same names which were incessantly in the mouths of the people, and whose inaptitude would be every moment perceived.

And what, besides, would all these systems come to, had the figures and the names of the zodiacal constellations been given to them without any relation to the course of the sun; as their inequality, the extension of several of them beyond the zodiac, and their manifest connection with the neighbouring constellations, seem to demonstrate was the case[240].

What would still happen, if, as Macrobius expressly says[241], each sign must have been an emblem of the sun, considered in some one of its effects or of its general phenomena, and without reference to the months when it passes, whether into the sign, or to its opposite?

Lastly, What if the names had been given in an abstract manner to the divisions of space or time, as they are now given by astronomers to what they call the signs, and had not been applied to the constellations or groups of stars, but at a period determined by chance, so that nothing could be concluded from their signification[242]?

In these suggestions there is, without doubt, enough to give an ingenuous mind a distaste for seeking to find in astronomy proofs of the antiquity of the nations. But were these alleged proofs as certain as they are vague and destitute of any satisfactory result, what could be concluded from them against the great catastrophe, which has left monuments amply demonstrative in other respects of its existence? All that can be admitted in this matter is, what some moderns have thought, that astronomy was among the number of the sciences preserved by those whom this catastrophe dispersed.

_Exaggerations relative to the Antiquity of certain Mining Operations._

The antiquity of certain mining operations has also been much exaggerated. A very late writer has imagined, that the mines of the island of Elba, judging from the rubbish carried out of them, must have been wrought for more than 40,000 years; but another author, who has also examined this rubbish with attention, has reduced the period in question to a little more than 5000 years,[243] and this even on the supposition that the ancients did not extract annually more than a fourth part of the quantity of ore now wrought. But what reason could there be to suppose that the Romans, for example, who consumed so much iron in their armies, derived so little advantage from these mines? Moreover, if these mines had been wrought for even 4000 years only, how should iron have been so little known in the times of remote antiquity?

_General Conclusion relative to the Period of the last Revolution._

I agree, therefore, with MM. Deluc and Dolomieu, in thinking, that if any thing in geology be established, it is, that the surface of our globe has undergone a great and sudden revolution, the date of which cannot be referred to a much earlier period than five or six thousand years ago; that this revolution overwhelmed and caused to disappear the countries which were previously inhabited by man, and the species of animals now best known; that, on the other hand, it laid dry the bottom of the last sea, and formed of it the countries which are at the present day inhabited; that it is since the occurrence of this revolution that the small number of individuals dispersed by it have spread and propagated over the newly exposed lands, and, consequently, that it is since this epoch only, that human societies have assumed a progressive march, that they have formed establishments, raised monuments, collected natural facts, and invented scientific systems.

But the countries which are at present inhabited, and which the last revolution laid dry, had already been previously inhabited, if not by men, at least by land animals, and, therefore, one preceding revolution at least had put them under water; and if we may judge by the different orders of animals the remains of which are observed in them, they had perhaps been subjected to two or three irruptions of the sea.

_Further Researches to be made in Geology._

These alternations now appear to me to form the problem in geology that it is of most importance to solve, or rather to define and circumscribe within due limits; for, in order to resolve it satisfactorily, it would be necessary to discover the cause of these events,--an undertaking which presents a difficulty of quite a different kind.

I repeat it, we see pretty clearly what is going on at the surface of the continents in their present state; we have formed a tolerable conception of the uniform progress and regular succession of the primitive formations, but the study of the secondary formations has been little more than merely commenced. That wonderful series of unknown zoophytes and marine mollusca, succeeded by reptiles and fresh-water fishes equally unknown; and these again replaced, in their turn, by other zoophytes and mollusca, more nearly related to those of the present day; those land animals, and those equally unknown fresh water mollusca and other animals which next occupied the surface, to be again displaced but by mollusca and other animals similar to those of our present seas; the relations of these diversified beings to the plants the remains of which accompany theirs, the connection of these two kingdoms with the mineral strata in which they are deposited; the greater or less uniformity existing between these different orders of beings in the different basins;--these are phenomena which appear to me imperiously to demand the attention of philosophers.

Rendered interesting by the variety of the products of the partial or general revolutions of this epoch, and by the abundance of the various species that figure alternately on the stage, this study is divested of the dryness of that of the primordial formations, and does not, like it, almost necessarily launch into hypotheses. The facts are so direct, so curious, and so evident, that they are sufficient, so to speak, to satisfy the most ardent imagination; and the conclusions to which they lead from time to time, however scrupulous the observer may be, having nothing vague in them, are equally free of any thing arbitrary. In fine, it is in those events that approach nearer to our own times, that we may hope to find some traces of more ancient events, and of their causes; if, indeed, after so many fruitless attempts as have been already made, one may be permitted to flatter himself with such a hope.

These ideas have haunted, I may almost say have tormented me, during my researches among fossil bones, the results of which I have lately presented to the public; researches which embrace but a very small part of those phenomena of the age preceding the last general revolution of the globe, and which are yet intimately connected with all the others. It was almost impossible that the desire should not arise of investigating the general mass of these phenomena, at least as they occur in a limited space around us. My excellent friend, M. Brongniart, in whose mind other studies excited the same desire, had the complaisance to associate me with himself in the task; and it is thus that we have laid the first foundations of our labours upon the environs of Paris. But this work, while it still bears my name, has become almost entirely that of my friend, from the infinite attention which he has bestowed, since the first conception of our plan, and since our journeys, upon the profound investigation of the objects, and the perfecting and arranging of the whole. I have placed it, with M. Brongniart’s consent, in the second part of my “Recherches,” in that in which I treat of the fossil bones of our neighbourhood. Although apparently relating only to a rather limited extent of country, it affords numerous results, which are applicable to geology in general, and, in this point of view, it may be considered as intimately connected with the present discourse; at the same time, that it is, without a doubt, one of the best ornaments of my work[244].

In it there is presented the history of the most recent changes that have taken place in a particular basin, and it descends so far as the Chalk formation, the extent of which over the globe is vastly more considerable than that of the materials of the basin of Paris. The chalk, which has been considered so modern, is thus found to be advanced in antiquity among the ages of the great period preceding the last catastrophe. It forms a sort of limit between the most recent formations, those to which the name of _Tertiary_ may be reserved, and the formations which are named _Secondary_, which have been deposited before the Chalk, but after the Primitive and Transition formations.

_Recapitulation of the Observations upon the Succession of the Tertiary Formations._

The most superficial strata, those deposits of mud and clayey sand, mixed with rolled pebbles, that have been transported from distant countries, and filled with bones of land animals, the species of which are for the most part unknown, or at least foreign to the country in which they are found, seem especially to have covered all the plains, filled the bottom of all the caverns, and choked up all the fissures of rocks that have come in their way. Described with particular care by Mr Buckland, under the name of _diluvium_, and very different from those other beds equally consisting of transported matters, continually deposited by torrents and rivers, which contain only bones of animals that still live in the country, and distinguished by the name of _alluvium_, the former are now considered by all geologists as exhibiting the most obvious proof of the immense inundation which has been the last of the catastrophes of our globe[245].

Between this diluvium and the chalk, are the formations alternately filled with fresh water and salt water productions, which mark the irruptions and retreatings of the sea, to which this part of the globe has been subjected, since the deposition of the chalk-strata: first, marls and buhrstones, or cavernous quartz, filled with fresh-water shells, similar to those of our marshes and pools; under them marls, sandstones, and limestones, all the shells of which are marine, such as oysters, &c.

At a greater depth are found fresh water formations of an older date, and particularly those famous gypsum deposits of the neighbourhood of Paris, which have afforded so much facility in ornamenting the buildings of that great city, and in which we have discovered whole genera of land-animals, of which no traces had been elsewhere perceived.

They rest upon those not less remarkable beds of limestone, of which our capital is built, in the more or less compact texture of which the patience and sagacity of our naturalists, and of several ardent collectors, have already detected more than 800 species of shells, all of them marine, but the greater part unknown in the presently-existing sea. They also contain only bones of fishes, and of cetacea and other marine mammifera.

Under this marine limestone there is another fresh water deposit, formed of clay, in which there are interposed large beds of lignite (brown coal), or that sort of fossil-coal which is of more recent origin than the common or black coal. Among shells, which are always of fresh water origin, there are also found bones in the deposit; but, what is remarkable, bones of reptiles, and not of mammifera. It is filled with crocodiles and tortoises, but the genera of extinct mammifera which the gypsum contains, are not found in it: they evidently did not exist in the country when these clays and lignites were formed.

This fresh water formation, the oldest which has been distinguished in our neighbourhood, and which supports all the formations which we have just enumerated, is itself supported and embraced on all sides by the chalk, an immense formation, both as to thickness and extent, which shews itself in very distant countries, such as Pomerania and Poland; but which, in our vicinity, reigns with a sort of continuity in Berri, Champagne, Picardy, Upper Normandy, and a part of England, and thus forms a great circle, or rather a great basin, in which the deposits of which we have been speaking are contained, but of which they also cover the edges in the places where they were less elevated.

In fact, it is not in our basin only that these various formations have been deposited. In the other countries where the surface of the chalk presented similar cavities for them; in those even where there was no chalk, and where the older formations alone presented themselves as supports, circumstances often led to the formation of deposits more or less similar to ours, and containing the same organic bodies.

Our formations containing fresh-water shells, have been seen in England, in Spain, and even so far as the confines of Poland.

The marine shells interposed between them, have been found along the whole course of the Appenines.

Some of the quadrupeds of our gypsum deposits, our palæotheria, for example, have also left their bones in certain gypseous formations of the Velai, and in the molasse quarries of the south of France.

Thus the partial revolutions which have taken place in our neighbourhood, between the period of the chalk and that of the great inundation, and during which the sea threw itself upon our districts or retired from them, had also taken place in a multitude of other countries. It seems as if the globe had undergone a long series of changes by which variations were produced, probably in close succession, as the deposits which they have left nowhere shew much thickness or solidity. The chalk has been produced by a more tranquil and more continuous sea; it contains only marine productions, among which there are, however, some very remarkable vertebrate animals, but all of the class of reptiles and fishes; large tortoises, vast lizards, and other similar animals.

The formations anterior to the chalk, and in the hollows of which the chalk is itself deposited, as the formations of our neighbourhood are in its hollows, form a great part of Germany and England; and the efforts which the naturalists of these two countries have recently made according with ours, and proceeding upon the same principles, combined with those which had been previously tried by the school of Werner, will soon leave nothing to be desired with respect to our knowledge of them. Messrs de Humboldt and de Bonnard in France and Germany, and Messrs Buckland and Conybeare in England, have furnished the most complete and most instructive accounts of them.

* * * * *

The subjoined table, in which not only the secondary formations have been arranged, but the whole series of strata, from the oldest known to the most modern and most superficial, has been politely furnished me by M. de Humboldt, to adorn my work. It may be considered as an epitome of the labours of geologists up to the present period[246].

_TABLE of Geological Formations in the order of their superposition._ By M. Al. de Humboldt.

Under the chalk are found deposits of green sand, of which its lower strata contains some organic remains. Beneath this are ferruginous sands. In many countries both of these deposits are agglutinated into beds of sandstone, in which lignites, amber, and remains of reptiles, are also observed.

Under this, we find the great mass of strata which compose the Jura chain, and that of the mountains by which it is continued into Suabia and Franconia, the principal ridges of the Apennines, and multitudes of beds in France and England. It consists of limestone-schists, rich in fishes and crustacea; vast beds of oolites, or of a granular limestone; grey marly limestones, with pyrites, characterised by the presence of ammonites, of oysters with recurvate valves, named Gryphææ, and of reptiles, which are remarkable on account of their forms and structures.

Large beds of sand and sandstone, often presenting vegetable impressions, support all these Jura deposits, and are themselves supported by a limestone, the innumerable shells and zoophytes contained in which induced Werner to give it the much too general name of _Shell-limestone_, and which is separated by other beds of sandstone, of the kind denominated _variegated_ sandstone, from a still older limestone, which has been not less improperly called _Alpine limestone_, because it composes the High Alps of the Tyrol; but which also shews itself at the surface in the eastern provinces of France, and in the whole southern part of Germany.

In this shell-limestone are deposited great masses of gypsum and rich beds of salt; and under it are found the thin beds of copper-slates so rich in fishes, among which there are also fresh-water reptiles. The copper-slate rests upon a red sandstone, to the epoch of which belong those famous deposits of coal, which supply the present inhabitants of the civilized countries of Europe with fuel, and are the remains of the first vegetable productions with which the face of the globe was adorned. We learn from the trunks of ferns, whose impressions they have preserved, how different these ancient forests have been from ours.

We then quickly come to those transition formations, in which primeval nature, nature dead and purely mineral, seems to have disputed the empire with organising nature. Black limestones, and schists which present only crustacea and shells of kinds now extinct, alternate with remains of primitive formations, and announce our having arrived at those formations, the oldest with which we are acquainted, those ancient foundations of the present envelop of the globe, the marbles and primitive slates, the gneisses, and, lastly, the granites.

Such is the precise enumeration of the successive masses with which nature has enveloped the globe. The positive geological information presented by it, has been obtained, by combining the knowledge furnished by mineralogy with that presented by the sciences connected with organic existence. This order, so new and so interesting in facts, has only been acquired by geology, since it preferred positive knowledge, furnished by observation, to fanciful systems, contradictory conjectures regarding the first origin of the globe, and all those phenomena, which, having no resemblance to what actually takes place in nature, could neither find in it, for their explanation, materials nor touchstone. A few years ago, the greater number of geologists might have been compared to historians, who, in writing the history of France, should have interested themselves only about the events which had taken place among the Gauls before the time of Julius Cesar. In composing their romances, however, these historians would have taken advantage of their knowledge of posterior facts; and the geologists of whom I speak, absolutely neglected the posterior facts, which could alone have reflected some light upon the darkness of preceding times.

_Enumeration of the Fossil Animals recognised by the Author._

In concluding this discourse, there only remains for me now to present the result of my own researches, or, in other words, a general account of my great work. I shall enumerate the animals which I have discovered, in the inverse order of that which I have followed in my enumeration of the formations. By proceeding deeper and deeper into the series of strata, I there rose in the series of epochs. I shall now take the oldest formations,--make known the animals which they contain,--and, passing from one epoch to another, point out those which successively make their appearance in proportion as we approach the present time.

We have seen that zoophytes, mollusca, and certain crustacea, begin to appear in the Transition formations; perhaps there may even at that period be bones and skeletons of fishes; but we do not by any means observe at so early a period remains of animals which live on land, and respire air in its ordinary state.

The great beds of coal, and the trunks of palms and ferns of which they preserve the impressions, although they afford evidence of the existence of dry land, and of a vegetation no longer confined to the waters, do not yet shew bones of quadrupeds, not even of oviparous quadrupeds.

It is only a little above this, in the bituminous copper-slates, that we see the first traces of them; and, what is very remarkable, the first quadrupeds are reptiles of the family of lizards, very much resembling the large monitors which live at the present day in the torrid zone. Several individuals of this kind have been found in the mines of Thuringia[247], among innumerable fishes of a genus now unknown, but which, from its relations to the genera of our days, appears to have lived in fresh water. Every body knows that the monitors are also fresh water animals.

A little higher is the limestone called Alpine, and resting upon it the shell-limestone, so rich in entrochites and encrinites, which forms the basis of a great part of Germany and Lorraine.

In it have been found skeletons of a very large sea-tortoise, the shells of which might have been from six to eight feet in length; and those of another oviparous quadruped of the family of lizards, of a large size, and with a very sharp muzzle[248].

Rising still through sandstones, which present only vegetable impressions of large arundinaceæ, bamboos, palms, and other monocotyledonous plants, we come to the different strata of the deposit which has been named the Jura limestone, on account of its forming the principal nucleus of that chain of mountains.

It is here that the class of Reptiles assumes its full development, and shews itself under the most varied forms and gigantic sizes.

The middle part, which is composed of oolites and lias, or of grey sandstone containing gryphites, contains the remains of two genera, the most extraordinary of all, which have combined the characters of the class of oviparous quadrupeds with organs of motion similar to those of the cetacea.

The _ichthyosaurus_[249], discovered by Sir Everard Home, has the head of a lizard, but prolonged into an attenuated muzzle, armed with conical and pointed teeth; enormous eyes, the sclerotica of which is strengthened by a frame consisting of bony pieces; a spine composed of flat vertebræ, of a depressed circular form, and concave on both surfaces like those of fishes; slender ribs; a sternum and clavicles like those of lizards and ornithorynchi; a small and weak pelvis; and four limbs, of which the humeri and femurs are short and thick, while the other bones are flattened, and closely set like the stones in a pavement, so as to form, when enveloped with the skin, fins of a single piece, almost incapable of bending; analogous, in short, both as to use and organization, to those of cetacea. These reptiles have lived in the sea; on shore, they could only at most have crept in the hobbling manner of seals; at the same time after they have respired elastic air.

The remains of four species have been found:

The most extensively distributed (_I. communis_) has blunt conical teeth; its length sometimes exceeds twenty feet.

The second (_I. platyodon_), which is at least as large as the former, has compressed teeth, with round and bulging roots.

The third (_I. tenuirostris_), has slender and pointed teeth, and the muzzle thin and elongated.

The fourth (_I. intermedius_), is, as its name implies, intermediate between the last species and the common, with respect to the form of its teeth. The two latter species do not attain half the size of the two first.

The _plesiosaurus_, discovered by Mr Conybeare, must have appeared still more monstrous than the ichthyosaurus. It had the same limbs, but somewhat more elongated and more flexible; its shoulder and pelvis were more robust; its vertebræ had more of the forms and articulations of the lizards; but what distinguished it from all oviparous and viviparous quadrupeds, was a slender neck as long as its body, composed of thirty and odd vertebræ, a number greater than that of the neck of any other animal, rising from the trunk like the body of a serpent, and terminating in a very small head, in which all the essential characters of that of the lizard family are observed.

If any thing could justify those hydras and other monsters, the figures of which are so often presented in the monuments of the middle ages, it would incontestibly be this plesiosaurus.[250]

Five species are already known, of which the most generally distributed (_P. dolichodeirus_) attains a length of more than twenty feet.

A second species (_P. recentior_), found in more modern strata, has the vertebræ flatter.

A third (_P. carinatus_) shews a ridge on the under surface of its vertebræ.

A fourth, and lastly a fifth (_P. pentagonus_ and _P. trigonus_), have the ribs marked with five and three ridges.[251]

These two genera are found everywhere in the lias: they were discovered in England, where this rock is exposed in cliffs of great extent; but they have also been found since in France and Germany.

Along with these had lived two species of Crocodiles, the bones of which are also found deposited in the lias, among ammonites, terebratulæ, and other shells of that ancient sea. We have skeletons of them in our cliffs at Honfleur, where the remains are found, from which I have drawn up their characters.[252]

One of these species, the _Long-beaked Gavial_, has the muzzle longer, and the head more narrow, than the gavial or long-beaked crocodile of the Ganges; the bodies of its vertebræ are convex before, while in our crocodiles of the present day they are so behind. It has been found in the lias deposits of Franconia, as well as in those of France.

A second species, the _Short-beaked Gavial_, has the muzzle of ordinary length, less attenuated than the gavial of the Ganges, but more so than our crocodiles of St Domingo. Its vertebræ are slightly concave at each of their extremities.

But these crocodiles are not the only ones which have been deposited in the strata of these secondary limestones.

The beautiful oolite quarries of Caen have presented a very remarkable one, the muzzle of which is as long and more pointed than that of the long-beaked gavial, and its head more dilated behind, with wider temporal fossæ. Its stony scales, marked with small round cavities, must have rendered it the best defended of all the crocodiles.[253] Its lower teeth are alternately longer and shorter.

There is still another in the oolite of England; but there have only been found some portions of its cranium, which do not suffice to afford a complete idea of it.[254]

Another very remarkable genus of reptiles, the remains of which, although they are also found beyond the limits of the lias concretion, are especially abundant in the oolite and upper sands, is the _megalosaurus_, justly so named, for, along with the forms of the lizards, and particularly of the monitors, of which it has also the sharp-edged and dentated teeth, it presents so enormous a size, that if we suppose it to have possessed the proportions of the monitors, it must have exceeded seventy feet in length. It was, in fact, a lizard of the size of a whale.[255] It was discovered by Mr Buckland in England; but we have it also in France; and in Germany there are found bones, if not of the same species, at least of a species which can be referred to no other genus. It is to M. Sœmmering that we owe the first description of this last. He discovered the bones in strata lying above the oolite, in those limestone-schists of Franconia, long celebrated for the numerous fossil remains which they furnished to the cabinets of the curious, and which will be still more celebrated for the services which their employment in lithography render to the arts and sciences.

The crocodiles continue to make their appearance in these schists, and always of the long-muzzled or rostrated kind. M. de Sœmmering has described one (the _Crocodilus priscus_), the entire skeleton of a small individual of which was found nearly in as good a state of preservation, as it could have been in our cabinets.[256] It is one of those which most resemble the present gavial of the Ganges; the anterior or united part of its lower jaw, however, is less elongated; its lower teeth are alternately and regularly longer and shorter. It has ten vertebræ in the tail.

But the most remarkable animals which these limestone slates contain, are the flying lizards, which I have named _Pterodactyli_.

They are reptiles whose principal characters are, a very short tail, a very long neck, the muzzle much elongated, and armed with sharp teeth; the legs also long, and one of the toes of the anterior extremity excessively elongated, having probably served for the attachment of a membrane adapted for supporting them in the air, accompanied with four other toes of ordinary size, terminated by hooked claws. One of these strange animals, whose appearance would be frightful did they occur alive at the present day, may have been of the size of a thrush[257], the other of that of a common bat[258]; but it would appear from some fragments that larger species had existed[259].

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Essay on the Theory of the EarthChapter VI: Part 6

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