Chapter I (5)

If all the great and little causes of demolition are arrested by the slope of mountains and the growth of plants, the surface of the earth might then remain without any farther change; and this would be a fact in opposition to the present theory, which represents the surface of the earth as constantly tending to decay, for the purpose of vegetation, and as being only preserved from a quick destruction by the solid rocks protecting, from the ravages of the floods and sea, the loose materials of the land. It will therefore be proper to show, that this author's argument does not go to prove his proposition in the terms which he has given it, which is, that those sloped mountains are to last for ever, but only that these causes, which he has so well described, make the destruction of the mountains become more slow[9].

[Footnote 9: This also would appear to be a part of that wise system of nature, in which nothing is done in vain, and in which every thing tends to accomplish the end with the greatest marks of economy and benevolence. Had it been otherwise, and the demolishing powers of the land increased, in a growing rate with the diminution of the height, the changes of this earth and renovation of our continent, in which occasionally animal life must suffer, would necessarily require to be often repeated; and, in that case, chaos and confusion would seem to be introduced into that system which at present appears to be established with such order and economy that man suspects not any change; it requires the views of scientific men to perceive that things are not at present such as they were created; it requires all the observation of a natural philosopher to know that in this earth there had been change, although it is not every natural philosopher that observes the benevolence accompanying this constitution of things which must subsist in change.]

The slope which our author gives to his mountains, in order to secure them from the ravages of time, is that which, according to his own reasoning, renders them fertile and proper for the culture of man; but fertile soil yields always something to the floods to carry away; and, while any thing is carried from the soil, the land must waste, although it may not then waste at the rate of those within the valleys of the Alps. According to the doctrine of this author, our mountains of Tweeddale and Tiviotdale, being all covered with vegetation, are arrived at that period in the course of things when they should be permanent. But is it really so? Do they never waste? Look at the rivers in a flood;--if these run clear, this philosopher has reasoned right, and I have lost my argument. Our clearest streams run muddy in a flood. The great causes, therefore, for the degradation of mountains never stop as long as there is water to run; although, as the heights of mountains diminish, the progress of their diminution may be more and more retarded.

Let us now see how far our author has reasoned justly with regard to vegetation, which, he says, stops the effects of all the little causes of destruction; this is the more necessary, as, in the present theory, it is the little causes, long continued, which are considered as bringing about the greatest changes of the earth.

Along the courses of our rivers there are plains between the mountains of greater or lesser extent; these are almost always fertile, and generally cultivated when large; when small, they are in pasture. The origin of these fertile soils, and their perpetual change, is to be described with a view to show, that vegetation, although most powerful in stopping the ravages of water, and for accumulating soil retained by this means, does it only for a time; after which the soil is again abandoned to the ravages of the running water, when no more protected by the vegetation.

Let us suppose the river running upon the one side of the haugh (which is the name we gave those little fertile plains) and close by the side of the mountain. In this case the bed of the river is deepest at the side of the mountain, which it undermines, leaving a falling _(un éboulement)_ on that side; on the other side, the river shelves gradually from the plain, and leaves soil in its bottom or stony bed upon the side of the haugh, in proportion as it makes advances in carrying away the bank at the bottom of the sloping mountain. The part which vegetation takes in this operation is now to be considered.

When the river has enlarged its bed by preying upon one side, whether of the mountain or the haugh, the water only covers it in a flood; at other times, it leaves it dry. Here, among the rocks and stones, the feeds of plants, left by the water or blown by the wind, spring up and grow; and, in little floods, some sand and mud is left among those plants; this encourages the growth of other plants, which more and more retain the fertile spoils of the river in its floods. At last, this bed of the river is covered perfectly with plants, which having retained plenty of fertile soil, although still rooted among the stones, opposes to the river a resistance which its greatest velocity is not able to overcome. In this state, the haugh is always deepening or increasing its soil, and has its surface heightened. At last, when this soil becomes so high as only to be flooded now and then, it becomes most fertile, as the heavier parts are carried in the bed of the river, and the lighter soil deposited upon the plain. The operations of the river, upon the plain, thus increase at the same time the height and fertility of the haugh. But this operation, of accumulated soil upon the stony bottom, has a period, at which time the river must return again upon its steps, and sweep away the haugh which it had formed. This is the natural course of things; and it happens necessarily from the deepening of the soil. Let us then examine this operation.

When no more soil is left upon the stony bottom than is sufficient for the covering of the ground, and rooting of plants which are also fixed in the solid ground or bottom of the soil, the water is not able to carry away the plants; and these plants protect the surface of loose soil. When again there is a depth of soil accumulated upon the haugh, the surface only is protected by the vegetable covering. But what avails it to the soil to be protected from above, when undermined by the enemy! The vegetable roots now no longer reaching to the bottom where solidity is found, the tender soil below is easily washed away by the continued efforts of the stream; and the unsupported meadow, with the impregnable texture of its leaves, its roots, and its fibres, falls ruinously into the river, and is born away in triumph by the flood. The water thus reclaims its long deserted bed,--only in order to pass from it again, and circulate or meander from hill to hill in varying perpetually its course.

Now this progress of the river, or this changing of its bed, is determined by the strong resistance of the new made haugh, humbly standing firm in the protection of its vegetation, while the elevated surface of the older haugh, deserted by the inferior soil which it had ceased to protect, falls a victim to its exalted state, and passes away to aggrandize another. This is the fate of haughs or plains erected by the operations of a river, and again destroyed in the natural course of things, or in the very continuation of that active cause by which they had been formed.

The water is constantly carrying the moveable soil from the higher to the lower place; vegetation often disputes the possession of these spoils of ruined mountains for a while; but, in the end, this vegetable protector, not only delivers up to the destroying cause the mineral soil which it had preserved, but, by its buoyancy in water, it facilitates the transportation of the stony parts to which this fibrous body is attached. Over and over a thousand times may be repeated this alternate possession of the transferable soil, by moving water on the one part and by fixed vegetation on the other, but at last all must land upon the shore, whether the river tends. Thus the mountain and the plain, the vegetable earth and the plants produced in that soil, must all return into the sea from whence either they themselves or their materials had come. In proportion as the mountains are diminished, the haugh or plain between them grows more wide, and also on a lower level; but, while there is a river running in a plain, and floods produced in the seasons of rain, there can be nothing stable in this constitution of things evidently founded upon change.

The description now given is from the rivers of this country, where it is not unfrequent to see relicts of three or four different haughs which had occupied the same spot of ground upon different levels, consequently which had been formed and destroyed at different periods of time. But the same operation is transacted every where; it is seen upon the plains of Indostan, as in the haughs of Scotland; the Ganges operates upon its banks, and is employed in changing its bed continually as well as the Tweed[10]. The great city of Babylon was built upon the haugh of a river. What is become of that city? nothing remains,--even the place, on which it stood, is not known.

[Footnote 10: An Account of the Ganges and Burrampooter Rivers, by James Rennel, Esquire. Philosophical Transactions, 1781.]

CHAP. VII.

_The Same Subject continued, in giving a View of the Operations of Air and Water upon the Surface of the Land._

We have but to enlarge our thoughts with regard to things past by attending to what we see at present, and we shall understand many things which to a more contracted view appear to be in nature insulated or without a proper cause; such are those great blocks of granite so foreign to the place on which they stand, and so large as to seem to have been transported by some power unnatural to the place from whence they came. We have but to consider the surface of this earth as having been upon a higher level; as having been every where the beds of rivers, which had moved the matter of strata and fragments of rocks, now no more existing; and as thus disposed upon different planes, which are, like the haughs of rivers, changing in a continual succession, but changing upon a scale too slow to be perceived. M. de Luc has given a picture which is very proper to assist our imagination in contemplating a more ancient state of this earth, although in this he has a very different end in view, and means to show that the world, which we inhabit at present, is of a recent date. It is in the 32d letter of his Histoire de la Terre, which I beg leave here to transcribe.

«Des montagnes basses (comme le _Jura_, qui est bas comparativement aux Alpes) sont bientôt fixées par ce moyen. Il ne se fait presque qu'un seul _talus_ depuis leur sommet jusques dans les basses vallées, ou sur la plaine. Aussi l'état de ces montagnes est-il déjà presqu'entièrement _fixé_: on y voit très peu de rochers nuds qui s'éboulent, excepté, auprès des _rivières_. C'est dans ces lieux-la que l'ouvrage tarde le plus à se finir. Le bas des _talus_ est miné par l'eau; leur surface s'éboule donc, pour ainsi dire, sans cesse, et laisse à découvert les rochers des sommets, qui par la continuent aussi à _s'ébouler_. Mais les vallées s'élargissent enfin; et les _talus_ s'éloignant ainsi des _rivières_, commencent à éprouver les influences du repos.»

Here nothing can be more positively described than the natural destruction of those mountains by the operation of the rivers which run between them; and this is from the authority of matter of fact, which, on all occasions, this author faithfully describes. At the same time, we are desired to believe, upon no better authority than the imagination of a person hurried on by system, that those mountains are absolutely to come to rest. I am aware of the danger to which a spirit of systematising leads; and I wish for nothing more than to have my Theory strictly examined, in comparing it with nature.

Our author thus proceeds: «La vue seule de la chaine du _Jura_ nous apprend donc ce que deviendroit enfin toutes les montagnes. Dans la plus grande partie de son étendue, il ne souffre plus aucun changement ruineux: la _végétation_ le recouvre presque partout. Les bas sont cultivés de toute sorte de manière suivant leur exposition; les sommets sont couverts de pelouses, qui forment les pâturages les plus precieux. Cette gazonade s'étend aussi sur toutes les parties des pentes qui ne sont pas trop rapides, et le reste est couvert de bois.

«J'ai parcouru fort souvent le pied de ces montagnes: leur état est presque partout tel que je viens d'avoir l'honneur de la descrire à V.M. J'ai sur-tout observé avec attention les lits des _torrens_ qui, en descendent pour se rendre dans les lacs de _Geneva_, de _Neufchâtel_ et de _Bienne_, ainsi que dans l'Aar et dans le Rhin: et hormis ceux de ces _torrens_ qui viennent des gorges où les terrains sont encore escarpés, ils ne roulent plus que l'ancien gravier qu'ils out apporté autrefois.

«Mais il n'en est pas ainsi des _Alpes_, des _Pyrénées_, et des autres montagnes, qui, comme celles-là, sont beaucoup plus élevées, ou qui sans l'être davantage ont été livrées aux influences de l'air dans un désordre plus grand. Dans ce genre de montagnes il reste encore à la _végétation_ de bien grandes conquêtes à faire.

«Ces montagnes ne sont pas telles que V.M. pourroit se les figurer naturellement; il faut y être monté pour s'en former une juste idée. Ce sont des montagnes sur d'autres montagnes. De près on ne voit que les parties inférieures; de loin tout se confond; il faut donc être arrivé sur une des premières _terrasses_ pour voir les secondes; sur celles-ci pour les troisièmes; et ainsi de suite.

«La plupart de ces _terrasses_ successives sont de grandes plaines, dominées par des rochers qui s'éboulent, et forment des _talus_. Si dans la succession des siècles, les _éboulemens_ de ces bandes de rochers en amphithéâtre finissoient sans emporter les plaines qu'ils soutiennent, et que les _torrens_ eussent creusé leur lit pendant ce tems là à quelque distance des _talus_ tout seroit fini par cette première operation. Mais il y a peu de hautes montagnes où les arrangemens soient si simples: souvent ces bandes empiètent les unes sur les autres en _s'éboulant_, et alors le repos est bien différé.

«Supposons que ces _terrasses_ soient étroites, et que leurs murs, c'est-à-dire les rochers qui les soutiennent, soient fort élevés. Les _terrasses_ alors ne suffiront pas pour recevoir les _éboulemens_ qui doivent se faire sur elles car le dessus de chacune d'elles s'étrécit de plus en plus par la destruction du rocher qui la soutient. Il pourra donc arriver que ce talus, s'étant étendu jusqu'au bord de la terrasse, se trouve reposer sur une base qui s'éboule encore; et même cela arrive très souvent; de sorte qu'à chaque rétrécissement de la base, le _talus_ lui-même s'éboule. Ainsi deux _talus_, qui étoient peut-être déjà en pleine végétation par la lenteur des éboulemens des rochers qui les formoient, pourront être fort reculés à cet égard; le _talus_ supérieur, parce que la surface fertilisée glissera en bas; et le _talus_ inférieur, parce que la sienne sera ensevelie sous de nouveaux décombres.

«Les montagnes qui sont dans ce cas seront proportionnellement plus abaissées que les autres; parce que leurs _talus_ se confondant ainsi et devenant par là fort étendus demeureront longtemps à devenir solides. Les eaux partant de fort haut, auront le tems de s'y rassembler et de devenir destructives vers le bas. Au lieu que dans les montagnes où les terrasses subsisteront encore après que tous les rochers se seront _éboulés_, les eaux étant reçues par reprises, perdront beaucoup de leur rapidité. Elles se rassembleront dans les enfoncemens des petites vallées supérieures, elles s'y formeront des lits qu'elles ne rongeront presque point; et la _végétation_ restera tranquille partout.»

Let us now consider the height of the _Alps_, in general, to have been much greater than it is at present; and this is a supposition of which we have no reason to suspect the fallacy; for, the wasted summits of those mountains attest its truth. There would then have been immense valleys of ice sliding down in all directions towards the lower country, and carrying large blocks of granite to a great distance, where they would be variously deposited, and many of them remain an object of admiration to after ages, conjecturing from whence, or how they came. Such are the great blocks of granite which now repose upon the hills of _Saleve_. M. de Saussure, who has examined them carefully, gives demonstration of the long time during which they have remained in their present place. The lime-stone bottom around being dissolved by the rain, while that which serves as the basis of those masses stands high above the rest of the rock, in having been protected from the rain. But no natural operation of the globe can explain the transportation of those bodies of stone, except the changed state of things arising from the degradation of the mountains.

Every thing, therefore, tends to show that the surface of the earth must wear; but M. de Luc, although he allows the principles on which this reasoning is founded, labours to prove that those destructive causes will not operate in time. Now, What would be the consequence of such a system?--That the source of vegetation upon the surface of the earth would cease at last, and perfect sterility be necessarily the effect of allowing no farther degradation to the surface of the earth; for, What is to supply the matter of plants? Water, air, and light alone, will not suffice; there are necessarily required other elements which the earth alone affords. If, therefore, this world is to continue, as it has done, to form continents of calcareous strata at the bottom of the ocean, the animals which form these strata, with their _exuviae_, must be fed. But, on what can they be fed? not on water alone; the consequence of such a supposition would lead us to absurdity; nor can they be fed on any other element without the dissolution of land. According to my views of things, it is certain that those animals are ultimately fed on vegetable bodies; and it is equally certain, that plants require a soil on which they may not only fix their fibrous roots, but find their nourishment at least in part; for, that air, water, and the matter of light, also contribute, cannot be doubted. But if animals, which are to form the strata of the earth, are to be fed on plants, and these are to be nourished by the matter of this earth, the waste of vegetable matter upon the surface of the earth must be repaired; the exhausted soil must be transported from the surface of the land; and fertility must be restored by the gradual decay of solid parts, and by the successive removal of soil from stage to stage. What a reverie, therefore, is that idea, of bringing the earth to perfection by fixing the state of its vegetable surface!

The description of those natural operations, which M. de Luc has given with a view to establish the duration of the mountains, is founded upon nothing but their destruction. These beds of rivers, which, according to our author, are _hardly_ to be wasted any more, will not satisfy a philosopher, who requires to see no degree of wasting in a body which is to remain for ever, or continue without change. But, however untenable this supposition of a fixed state in the surface of this earth, the accuracy of the natural philosopher may still be observed in the absurdity of the proposition. «L'état des _montagnes_ sera _fixe_, partout où les _rivières_ seront arrivées au point de n'emporter pas plus de limon hors de leur enceinte, que l'air et les pluies n'y déposeront de _terre végétable_, et voila enfin quel sera le repos, l'état permanent de la surface de notre globe. Car alors il y aura compensation entre les destructions et les réparations simultanées, et les montagnes sûrement ne s'abaisseront plus.»

Surely, if there is in the system of nature wisdom, we may look for compensation between the destroying and repairing operations of the globe. But why seek for this compensation in the _rest_ or immobility of things? Why suppose perfection in the want of change? The summit of the Alps was once the bottom of the sea; the existence of our land depended then upon the change of seas and continents. But has the earth already undergone so great changes, and is it not yet arrived at the period of its perfection? How can a philosopher, who is so much employed in contemplating the beauty of nature, the wisdom and goodness of Providence, allow himself to entertain such mean ideas of the system as to suppose, that, in the indefinite succession of time past, there has not been perfection in the works of nature? Every material being exists in motion, every immaterial being in action and in passion; rest exists not any where; nor is it found in any other way, except among the parts of space. Surely it is contrary to every species of philosophy, whether ancient or modern, to found a system on the inutility of repose, or place perfection in the vacuity of rest, when every thing that truly exists, exists in motion; when every real information which we have is derived from a change; and when every excess in nature is compensated, not by rest, but by alternation.

M. de Luc allows the rivers to carry matter always to the sea; but then, at a certain period, this matter carried by the floods is to be compensated to the mountains by the vegetable earth received from the air and rains. Here is a proposition which should be well considered, before it be admitted as a principle, which shall establish the perpetuity of these mountains, if it be true; or, if false, assure us of their future demolition. Let us now examine it.

If from air and rain there is produced earth which cannot afterwards be resolved by the operation of those elements, and thus again dissolved in the air and water of the land, then this author might have had some pretext, however insufficient, for alledging that it might be possible to compensate the loss of mineral substances, carried off the surface of the earth, by the production of this vegetable matter from the air and rain; but, when there is not sufficient reason to conclude that any substance, produced in vegetation, can resist the continued influences of the air and water, without being decomposed in its principles, and at last entirely dissolved in water, the cautious argument here employed by this author, for the permanency of mountains, must appear as groundless in its principle as it would be insufficient for his purpose, were it to be admitted; but this will require some discussion.

That which preserves vegetable bodies so long from dissolution in water, is what may be called the inflammable or phlogistic composition of those bodies. This composition is quickly resolved in combustion; but it is no less surely resolved by the influences of the sun and atmosphere, only in a slower manner. Therefore, to place the permanency of this earth, or any of its surface, upon a substance which in that situation necessarily decays, is to form a speculation inconsistent with the principles of natural philosophy[11].

[Footnote 11: It is from inadvertency to this fact in natural history, the consuming of vegetable substances exposed to the influences of the atmosphere, that M. de Luc, in his _Histoire de la Terre_, has pretended to determine the past duration of the German heaths as not of a very high antiquity. He has measured the increase of the vegetable soil, an increase formed by the accumulation of the decayed heath; and, from the annual increase or deposits of vegetable matter on that surface, he has formed a calculation which he then applies to every period of this turfy augmentation, not considering that there may be definitive causes which increase with this growing soil, and which, increasing at a greater rate in proportion as the soil augments, may set a period to the further augmentation of that vegetable soil. Such is fire in the burning of those parched heaths; such is the slower but constant and growing operation of the oxygenating atmosphere upon this turfy substance exposed to the air and moisture. This author has very well described the constant augmentation of this vegetable substance in the morasses of that country, as it also happens in those of our own; but there is a wide difference in those two cases of peat bog and healthy turf; the vegetable substance in the morass is under water, and therefore has its inflammable quality or combustible substance protected from the consuming operation of the vital or atmospheric air; the turfy soil, on the contrary, is exposed to this source of resolution in the other situation.]

But even supposing that the degradation of mountains were to be suspended by the pretended compensation which is formed, by the rivers carrying mineral mud into the sea, and the air and rain producing vegetable earth; in what must this operation end? In carrying into the sea, to be deposited at its bottom, all the vegetable earth produced by the air and rain. But our cosmologist, in thus procuring an eternal station to his mountains, has not told us whether this transmutation of the air and rain be a finite operation, or one that is infinite; whether it be in other respects confident with the natural operations of the globe; and whether, to have the air and water of the globe converted into earth, would ultimately promote, or not, that perfection which he wishes to establish. Here, therefore, in allowing to this philosophy all its suppositions, it would be necessary to make another compensation, in preserving mountains at the expense of air and rain; and, the waste of air and water, which are limited, would require to be repaired.

It is not in our purpose here to treat of moral causes; but this author having endeavoured to fortify his system by observing, that the world certainly cannot be ancient, since men have not ceased as yet to quarrel and fight, (Lettre 34.) it may be proper to observe, that the absolute rest of land, like the peace among mankind, will never happen till those things are changed in their nature and constitution, that is to say, until the matter of this globe shall be no more a living world, and man no more an animal that reasons from his proper knowledge, which is still imperfect. If man must learn to reason, as children learn to speak, he must reason erroneously before he reasons right; therefore, philosophers will differ in their opinions as long as there is any thing for man to learn. But this is right; for, how are false opinions to be corrected, except in being opposed by the opinions of other men? It is foolish, indeed, for men to quarrel and fight, because they differ in opinion. Man quarrels properly, when he is angry; and anger perhaps is almost always ultimately founded upon erroneous opinion. But, in nature, there is no opinion; there is truth in every thing that is in nature; and in man alone is error. Let us, therefore, in studying nature, learn to know the truth, and not indulge erroneous notions, by endeavouring to correct, in nature, that which perhaps is only wrong in our opinion.

Having shown that every thing, which is moveable upon the surface of the land, tends to the sea, however slowly in its pace, we are now to examine, what comes of those materials deposited within the regions of the waves, still however within the reach of man, and still subservient more immediately to that soil on which plants grow, and man may dwell.

As, from the summit of the land, the natural tendency of moveable bodies is to fall into the water of the sea, so, from the borders of the land or coast, there being a declivity towards the deepest bottom of the sea, and there being currents in the waters of the ocean occasionally rendered more rapid on the shore, every moveable thing must tend to travel from the coast, and to proceed alone; the shelving bottom of the sea into the unfathomable deep, when they are beyond the reach of man or the possibility of returning to the shore.

But it is not every where upon the coast that those materials are equally delivered; neither is it every where along the shore that the currents of the ocean are equally perceived, or operate with equal power in moving bodies along the shelving bottom of the sea. Hence in some places deep water is found washing rocky coasts, where the waste of land is only to be perceived from what is visibly wanting in the continuity of those hard and solid bodies. In other places, again, the land appears to grow and to encroach upon the space which had been occupied by the sea; for here the materials of the land are so accumulated on the coast, that the bottom of the sea is filled up, and dry land is formed in the bafon of the sea, from those materials which the rivers had brought down upon the shore.[12]

[Footnote 12: We are not however to estimate this operation, of forming soil by the muddy waters of a river depositing sediment, in the manner that M. de Luc has endeavoured to calculate the short time elapsed in forming the marshlands of the Elbe. This philosopher, with a view to show that the present earth has not subsisted long since the time it had appeared above the surface of the sea, has given an example of the marsh of _Wisebhafen_ where the earth, wasted by inundation, was in a very little time replaced, and the soil heightened by the flowings of the Elbe, and this he marks as a leading fact or principle, in calculating the past duration of our continents, of which he says, we are not to lose sight (Tome 5, p. 136.) But here this philosopher does not seem to be aware, that he is calculating upon very false grounds, when he compares two things which are by no means alike, the natural operations of a river upon its banks, making and unmaking occasionally its haughs or level lands, that is to say, alternately making and destroying, and the artificial operations of man receiving the muddy water of a tide-way into the still water of a pond formed by his ramparts; yet, it is by this last operation that our author forms an estimate which he applies to the age of this earth, in calculating how long time might have been required for producing the marsh lands of the Elbe.

I would here ask if he can calculate what time it may have required to hollow out the bed of the Elbe from its source to the sea; and to tell how often the marsh-lands, which he now sees cultivated, had been formed and destroyed by the river before they were cultivated in their present state; or if there is any security that they shall not again be taken away by the river, and again formed in the same place. If this is the case, that the river is constantly changing the fertile lands, which it forms by its inundation, what judgement are we to form by calculating the quantity of sediment in a certain measure of its muddy water.]

Holland affords the very best example of this fact. It is a low country formed in the sea. This low land is situated in the bottom of a deep bay, or upon the coast of a shallow sea, where more materials are brought by the great rivers from the land of Germany than what the currents of the sea can carry out into the deep. Here banks of sand are gathered together by streams and tides; this sand is blown in hillocks by the wind; and those sand hills are retained by the plants which have taken root and fixed those moving sands. Behind that chain of hillocks, which line the sea shore, the waters of the rivers formed a lake, and the bottom of this lake had been gradually filled up or heightened by materials travelling in the rivers, and here finding rest. It grew up until it became a marsh; then man took possession of the soil; he has turned it to his own life; and, by artificial ramparts of his forming, preserves it in the present state, some parts above the level of the sea, others considerably below the ordinary rise of tides. M de Luc, who has given a very scientific view of this country in his Lettres Physiques et Morales, has there also furnished us with the following register of what had been found by sinking in that soil. It was at Amsterdam at the year 1605 in making a well.

«Voici la désignation des matières qui furent trouvées en partant de la surface.

51 pieds, mêlés _de sable tourbeux_, de fable
_des dunes pur_ et _d'argile_ ou
limon.

22.---de même _sable des dunes pur_,
et _d'argile_ bleuâtre.

14.---du même _sable_ pur.

87 pieds.--Ou rien encore n'indiquoit la
présence de la mer.

55.---de _sable marin_, et _de limon_,
mêles l'un et l'autre de _coquilles_
dans plusieurs couches.

142 pieds.--Soit la plus grande profondeur,
où s'est manifestée la _présence_
de la mer.

49.---_Argille_ dure sans mélange de
coquilles, soit que ce soit une
couche _argilleuse continentale,_
ou les premiers dépôts des
fleuves; ce qu'il est difficile de
Déterminer.

191 pieds.

13.---Sable mêlé de pierres; qui est
enfin sûrement le _sol_ vierge
continental.

28.---Sable pur; continental encore;
car j'ai remarqué partout
dans la _Geest_, que c'est
dans la couche supérieure, à
une petite profondeur que se
trouvent les pierres; au-dessous
le _sable_ est pur.

232 pieds.--C'est à cette profondeur, ou
dans la masse de ces deux dernières
couches, que se trouva
l'eau douce, et par conséquent
le vrai _sol continental_.»

The light that we have from this pit which has been made in the soil, according to my view of the subject, is this, that here is the depth of 232 feet in travelled soil, and no solid bottom found at this distance from the surface or level of the sea. How far this depth may be from the bottom of these travelled materials is unknown; but this is certain, that all that depth, which has been sunk, had been filled up with those materials[13].

[Footnote 13: An interesting map for the use of natural history would be made by tracing the places (behind this country of loose or travelled soil) where the solid strata appear above the level of the sea. We should be thus able to form some notion of the quantity of materials which had been deposited in the water of this sea. But, though we might thus enlarge our views a little with regard to the transactions of time past, it would only be in a most imperfect manner that we would thus form a judgment; for, not knowing the quantity of sand and mud carried out by the currents from the German sea into the Atlantic, we could only thus perceive a certain minimum, which is perhaps a little portion of the whole.]

It will thus appear of what unstable materials is composed the land of that temporary country. It will also be evident, that, by removing the sand banks of this coast, the whole of this low country would be swallowed by the sea, notwithstanding every effort that the power of man could make. But it may be alledged, that those sand banks are increasing still with the alluvion of Germany, instead of being in a decreasing state. I should also incline to believe that this is truly the case; but, though we may acknowledge the growth of land upon the coast of Holland, we must deny that a stable country can be formed in the bed of the sea by such means. For, however increasing may be the sand in the German sea, and however great additions may be made of habitable country to the coast of Holland, yet, as the islands of Great Britain and Ireland are worn by attrition on the shores, and are wasted by being washed away into the ocean, the causes for the accumulation of sand in the German sea must cease in time, when, in this progress of things, the sand banks, on which depends the existence of Holland, must diminish, and at last be swept away, in leaving the solid coast of Germany to be again buffeted by the waves, as is at present the coasts of Ireland, France, and Spain.

This reasoning is, indeed, very far removed from that which is commonly employed for the purpose of conducting human operations, or establishing the political system of a nation; it is not, however, the less interesting to man, in that it cannot direct him immediately in his worldly affairs; and it is the only way of reasoning that can be employed in order to enlighten man with a view of those operations which are not to be limited in time, and which are to be concluded as in the system of nature, a system which man contemplates with much pleasure, and studies with much profit.

Thus we have shown, that, from the top of the mountain to the shore of the sea, which are the two extremities of our land, every thing is in a state of change; the rock and solid strath dissolving, breaking, and decomposing, for the purpose of becoming soil; the soil travelling along the surface of the earth, in its way to the shore; and the shore wearing and wasting by the agitation of the sea, an agitation which is essential to the purposes of a living world. Without those operations, which wear and waste the coast, there would not be wind and rain; and, without those operations which wear and waste the solid land, the surface of the earth would become sterile. But showers of rain and fertile soil are necessarily required in the system of this world; consequently, the dissolution of the rocks, and solid strata of the earth, and the gradual, flow, but sure destruction of the present land, are operations necessary in the system of this world; so far from being evils, they are wisely calculated, in the system of nature, for the general good.

CHAP. VIII.

_The present Form of the Surface of the Earth explained, with a View of the Operation of Time upon our Land_.

It is not to _common_ observation that it belongs to see the effects of time, and the operation of physical causes, in what is to be perceived upon the surface of this earth; the shepherd thinks the mountain, on which he feeds his flock, to have been always there, or since the beginning of things; the inhabitant of the valley cultivates the soil as his father had done, and thinks that this soil is coeval with the valley or the mountain. But the man of scientific observation, who looks into the chain of physical events connected with the present state of things, sees great changes that have been made, and foresees a different state that must follow in time, from the continued operation of that which actually is in nature.

It is thus that enlightened natural history affords to philosophy principles, from whence the most important conclusions may be drawn. It is thus that a system may be perceived in that which, to common observation, seems to be nothing but the disorderly accident of things; a system in which wisdom and benevolence conduct the endless order of a changing world. What a comfort to man, for whom that system was contrived, as the only living being on this earth who can perceive it; what a comfort, I say, to think that the Author of our existence has given such evident marks of his good-will towards man, in this progressive state of his understanding! What greater security can be desired for the continuance of our intellectual existence,--an existence which rises infinitely above that of the mere animal, conducted by reason for the purposes of life alone.

The view of this interesting subject, which I had given in the first part, published in the Transactions of the Edinburgh Royal Society, has been seen by some men of science in a light which does not allow them, it would appear, to admit of the general principle which I would thereby endeavour to establish. Some contend that the rivers do not travel the material of the decaying land;--Why?--because they have not seen all those materials moved. Others alledge, that stones and rocks may be formed upon the surface of the earth, instead of being there all in a state of decay. These are matters of fact which it is in the power of men who have proper observation to determine; it is my business to generalise those facts and observations, and to bring them in confirmation of a theory which is necessarily founded upon the decaying nature and perishing state of all that appears to us above the surface of the sea.

Nothing is more evident, than that the general effect of mineral operations is to consolidate that which had been in an incoherent state when formed at the bottom of the sea, and thus to produce those rocks and indurated bodies which constitute the basis of our vegetable soil; but, that indurating or consolidating operation is not the immediate object of our observation; and, to see the evidence of that operation, or the nature of that cause, requires a long chain of reasoning from the most extensive physical principles. Our present subject of investigation requires no such abstract distant _media_, by which the effect is to be connected with its cause; the actual operation in general is the object of our immediate observation; and here we have only to reason from less to more, and not to homologate things which may, to men of narrow principles, appear to be of different kinds. But even here we find difficulty in persuading those who have taken unjust views of things; for, those who will not deny the truth of every step in this chain of reasoning, will deny the end to which it leads, merely because they are not disposed to admit the progress of that order which appears in nature.

In the last chapter, I have been using arguments to prove that M. de Luc has reasoned erroneously, in concluding the future stability of a continent; and I have been endeavouring to show that our continent is necessarily wasted in procuring food to plants, or in serving the various purposes of a system of living animals. We have now in view to illustrate this theory of the degradation of the surface of the earth; a theory necessarily leading to that system of the world in which a provision is made for future continents; and a theory explaining various natural appearances which otherwise are not to be understood. A door may thus be opened for the investigation of natural history, particularly that which traces back, from the present state of things, those operations of nature which are more immediately connected with what we take much pleasure to behold, viz. the surface of the earth stored with such a variety of beautiful plants, and inhabited by such a diversity of animals, all subservient to the use of man.

There are two ways in which we may look for the transactions of time past, in the present state of things, upon the surface of this earth, and read the operations of an ancient date in those which are daily transacted under our eye. The one of these is to examine the soil, and to trace the origin of that which we find loose upon the surface of the earth, or only compacted by the soft and cohesive nature of some of its materials. In thus studying the soil we shall learn the destruction of the solid parts; and though, by this means, we cannot form an estimate of the quantity of this destruction which had been made, we shall, upon many occasions, see a certain _minimum_ of this quantity which may perhaps astonish us.

The second method here proposed, is to examine the solid part of the earth, in order to learn the quantity of matter which had been separated from this mass. Here also we shall not be able to compute the quantity of what had been destroyed; but we shall every where find a certain _minimum_ of this quantity, which will give us an extensive view with regard to the operation of the elements and seasons upon the surface of this earth. We shall now examine more particularly those two ways of judging with regard to the operations of time past, and the changes which have been made upon the surface of our land, by those active causes, which, being in the constitution of this earth, must continue to operate with undiminished power, and tend to preserve the _whole_ amidst the destruction of its particular parts.

The quality of the soil or travelled earth of the globe is various; because the solid parts, from the destruction of which the soil is formed, consist of very different substances, in the different portions of each country. Thus, in one part of a country, the soil will be calcareous, or containing much of that species of substance; in another, again, it will be argillaceous; in another sandy, where the prevailing substance is siliceous. These are the original soils; other substances may be considered as adventitious to this soil, though natural to the surface of the earth, which is covered with plants and animals. The substance of those animal and vegetable bodies, mixed with the soil, adds greater fertility to the earth, and gives a soil which is still more compounded in its nature, but still composed of those materials now enumerated.

We have been now supposing the solid parts below, or in the same field, as furnishing materials of which the soil is formed; this soil then partakes of the nature of those solid parts, whether more simple or more compound. There is, however, another subject of variety, or still greater composition in soils; this is the transportation of materials from a distance; and this, in general, is performed by the ablution of water, in following the declivity of the surface. But sand is sometimes travelled by the wind, and proceeds along the surface of the earth, without regard to the declivity, and changes the nature of soil in those places which happen to be exposed to this accident.

There cannot be any extensive, great, or distant travelling of sand or soil by means of the wind, except in those places which are sterile for want of rain, and thus are destitute of rivers and of streams; for, these running waters form every where a bar to this progressive movement of the soil, even if the sterility or dryness should permit the blowing of the sand. But the operation of streams and rivers, carrying soil and stones along the surface of the earth, is constant, great, and general over all the globe, so far as a superfluity of water, in the seasons of rain, falls upon the earth.

From the amazing quantity of those far travelled materials, which in many places are found upon the surface of the ground, we may with certainty conclude, that there has been a great consumption of the most hard and solid parts of the land; and therefore that there must necessarily have been a still much greater destruction of the more soft and tender substances, and the more light and subtile parts which, during those operations of water, had been floated away into the sea. This appears from the enormous quantities of stones and gravel which have been transported at distances that seem incredible, and deposited at heights above the present rivers, which renders the conveyance of those bodies altogether inconceivable by any natural operation, or impossible from the present shape of the surface. This therefore leads us to conclude, that the surface of the earth must have been greatly changed since the time of those deposits of certain foreign materials of the soil. Examples of this kind have been already given. I shall now give one from the Journal de Physique.

«Les bords du Rhône aux environs de Lyon, et sur la longueur de quarante lieues, et de plus, des montagnes entières, dans le même pays, sont formes de pierres dont on ne trouve les analogues que dans la Suisse. Ce fait presqu'incompréhensible est accompagné de beaucoup de circonstances qui méritent d'être détaillées dans un discours plus longue que celui-ci. Il y a cependant une que je ne peux pas m'empêcher de rapporter ici, comme une suite de ce que je viens de dire.

«Dans cette grand catastrophe, à laquelle j'attribue le transport de ces matières alpines, il se fit de grandes échancrures dans le Jura; les plus profondes que j'aie vues sont celles de Jougue de Sainte-Croix, du val de Mousthier Travers, de Someboz au val de Saint-Inver, une cinquième aux environs du village de Grange, trois lieues plus bas que Bienne, et une sixième à quatre à cinq lieues plus bas que Soleure, à l'endroit dit la cluse. Cette dernière est la plus profonde, et se trouve de niveau avec les eaux de l'Aar. Beaucoup de ces matières étrangères au Jura, ont passé par ces échancrures, et sans doute, par bien d'autres et se sont répandues, dans plusieurs de ces vallées. J'en ai vu un suite bien marquée qui a passé par Jougue, par Saint-Antoine, part Mont Perreux, les Grangettes, les Granges Friards, Oye, et qui est allée jusqu'aux plaines de Pontarlier. Cette suite est en ligne droite vis-à vis l'échancrure de Jougue, et la direction de la vallée qui est au bas de ce village. On en trouve quelques morceaux à Metabiefs, mais je n'en ai point vu aux Longevilles, ni à Roche-Jean. Il y en a au-dessus de Saint-Croix ou d'autres ont pu passer aussi pour aller de même aux environs de Portarlier. Il y en a dans le val de Mousthier-Travers jusqu'au dessus de village de Butte; elles ont même passé les roches de Saint-Sulpice du côté des Verrières de Suisse, ou l'on a été obligé d'en faire sauter de gros blocs avec de la poudre pour dégager la grande route; il y en a dans les vallées de Tavannes, et de Delemont; on en trouve bien plus loin, j'en ai vu près de Roulans, et je ne douterois pas que les pierres meulières de Moissez et des environs n'eussent la même origine.»

M. de Saussure, who has so well observed every thing that can be perceived upon the surface of the earth, gives us the following remarks which are general to mountainous countries. (Voyages dans les Alpes, tome 2d § 717).

«Dans le haut des vallées entourées de hautes montagnes, on ne voit point de cailloux roulées, qui soient étrangers à la vallée même dans laquelle on les trouve; ceux que l'on y rencontre ne sont jamais que les débris des montagnes voisines. Dans le plaines au contraire, et à l'embouchure des vallées, qui aboutissent aux plaines et même assez haut sur les pentes des montagnes qui bordent ces plaines, on trouve des cailloux et des blocs que l'on diroit tombés du ciel, tant leur nature diffère de toute ce que l'on voit dans les environs.»

Here are facts which can only be explained in supposing that the valleys have been hollowed out of the solid mass, by the gradual operation of the rivers. In that case stones, travelled from a far, will be found at considerable heights, upon the sides of the valleys at their under end, or where, as our author says, they terminate in plains.