Having thus examined the alpine countries both of the Old World and the New, it remains to observe some river in a more low or level country emptying itself into a sea that does not communicate with the ocean. The Wolga will now serve for this purpose; and we shall take our facts from the observations of those men of science who were employed by their enlightened Sovereign to give the natural as well as the economical history of her dominions.

Russia may be considered as a square plain, containing about 40 degrees of longitude, and 20 of latitude, that is, between the 47 deg. and 67 deg. degrees. The east side is bounded by the Oural mountains, running in a straight line from north to south. The west is bounded by Poland. The south reaches to the Caspian and Black Seas, as does the north to the Polar Ocean.

The greatest part of the water which falls upon this extensive country is delivered into the Caspian by the river Wolga; and this water runs from the east and west sides, gathered in two great rivers, the Kama and the Oka. The water thus gathered from the two opposite extremities of this great kingdom meet in the middle with the Wolga, which receives its water from the north side. We thus find the water of this great plain running in all directions to its centre. Had this been the lowest place, here would have been formed a sea or lake. But this water found a lower place in the bed of the Caspian; and into this bason it has made its way, in forming to itself a channel in the great plain of the Wolga.

Our present purpose is to show that this channel, which the Wolga has cut for itself, had been once a continued mass of solid rock and horizontal strata, which in the course of time has been hollowed out to form a channel for those waters. These waters have been traversing all that plain, and have left protuberances as so many testimonies of what had before existed; for, we here find the horizontal strata cut down and worn away by the rivers.

M. Pallas gives us very good reason to believe that the Caspian Sea had formerly occupied a much greater extent than at present; there are the marks of its ancient banks; and the shells peculiar to the Caspian Sea are found in the soil of that part of its ancient bottom which it has now deserted, and which forms the low saline Steppe. He also makes it extremely probable that the Caspian then communicated with the Euxine or Black Sea, and that the breaking through of the channel from the Euxine into the Mediterranean had occasioned the disjunction of those seas which had been before united, as the surface of the Caspian is lowered by the great evaporation from that sea surrounded with dry deserts.

However that may he, it is plain, that throughout all this great flat inland country of Russia, the solid rocks are decaying and wearing away by the operation of water, as certainly, though perhaps not so rapidly, as in the more mountainous regions of the earth.

If there is so much of the solid parts worn and washed away upon the surface of this earth, as represented in our Theory; and if the rivers have run so long in their present courses, it may perhaps be demanded, Why are not all the lakes filled up with soil; and why have not the Black and Caspian Seas become land or marshy ground, with rivers passing through them to the ocean? Here is a question that may be considered either as being general to all the lakes upon the earth, or as particular to every lake which should thus find a proper explanation in the Theory. With regard to the last of these, the question has already been considered in this view, when the particular case of the Rhone was taken as an example; and now we are only to consider the question as general to the globe, or so far as belonging to the Theory, without particularising any one case.

It must be evident, that the objection to the Theory, here supposed to be made, is founded necessarily upon this, that the solid basis of our continent, on whose surface are found the lakes in question, is preserved without change, because, otherwise, the smallest variation in the basis may produce the most sensible effects upon the surface; and in this manner might be produced dry land where there had been a lake, or a lake where none had been before. But, as the present Theory is founded upon no such principle of stability in the basis of our land, no objection, to the wasting operations of the surface of the earth, can be formed against our Theory, from the consideration of those lakes, when the immediate cause of them should not appear.

The natural tendency of the operations of water upon the surface of this earth is to form a system of rivers every where, and to fill up occasional lakes. The system of rivers is executed by wearing and wasting away the surface of the earth; and this, it must be allowed, is perfect or complete, at least so far as consistent with another system, which would also appear to be in nature. This is a system of lakes with which the rivers are properly connected. Now, as there are more way than one by which a lake may be formed, consistent with the Theory, the particular explanation of every lake must be left to the natural history of the place, so far as this shall be found sufficient for the purpose.

There are many places which give certain appearances, from which it is concluded, by most intelligent observators, that there had formerly existed great lakes of fresh water, which had been drained by the discharge of those waters through conduits formed by some natural operation; and those naturalists seem to be disposed to attribute to some great convulsion, rather than to the slow operation of a rivulet, those changes which may be observed upon the surface of the earth. Let us now examine some of those appearances, in order to connect them with that general system of moving water which we have been representing as every where modifying the surface of the earth on which we dwell.

It is the P. Chrysologue De Gy, who gives the following description. Journal de Physique, Avril 1787.

"La principaute de Porrentrui l'emporte encore en ce genre sur le reste du Jura a ce qu'il paroit. On pourra en juger sur les circonstances locales que je vais rapporter. Une partie de cette principaute est divisee en quatre grandes vallees, d'environs quatre lieues de long, sur trois quarts-d'heure ou une heure de large, separees par autant de chaines de montagnes fort eleves et large en quelques endroits d'une lieue et demie. Les extremites de chacune de ces vallees sont plus elevees que le milieu, et on ne peut pas en sortir par ces extremites sans beaucoup monter. Mais ces vallees ont des communications entr'elles par une pente assez douce a travers ces masses enormes de montagnes qui les separent, et qui sont coupees au niveau du milieu des vallees sur 300, 400, 500 toises de hauteur et dans toute leur largeur. On pourroit assez justement comparer ces vallees a des berceaux poses les uns a cote des autres, dont les extremites, remplies en talus, seroient plus eleves que les cotes, et dont ces cotes seroient coupes jusqu'au fond, pour laisser une passage de l'un a l'autre. Je connois sept a huit passages semblables a travers ces hautes montagnes, dans une quarre d'environ quatre a cinq lieues; et dont quatre aboutissent a la vallee de Mouthier-Grand-Val. Ces passages sont evases dans le dessus, d'environ une demi-lieue par endroits; mais leurs parois, en talus, se rejoignent dans le fond ou coule un ruisseau. On a pratique des routes sur quelques-uns de ces talus, mais les roches sont quelquefois si resserrees et si escarpees, qu'on a ete oblige de construire un canal sur le ruisseau, pour y faire passer la route. C'est-la que l'on voit a son aise, la nature de ces rochers primitives, leur direction, leur inclinaison, et tous leurs autres accidens qui demanderaient chacun une dissertation particuliere trop longue pour le moment, et il faut les avoir vues pour se faire une juste idee des sentimens de grandeur, de surprise, et d'admiration qu'elles inspirent, et que l'on ne peut pas exprimer par des paroles. Cependant, les sources de ruisseaux, ou si l'on veut des rivieres qui traversent ces montagnes, sont beaucoup plus basses que les sommites des montagnes elles-memes, ces sources ne font donc pas la cause de ces effets merveilleux. Il a fallu un agent plus puissant pour creuser ces abimes."

M. de la Metherie has taken a very enlightened view of the country of France; and has given us a plan of the different ridges of mountains that may be traced in that kingdom, (Journal de Physique, Janvier 1787). Now there is a double purpose in natural history to which such a plan as this may be applied; viz. first, to trace the nature of the solid parts, on which the soil for vegetation rests; and, secondly, to trace the nature of the soil or cultivated surface of the earth, on which depends the growth of plants.

With regard to the first, we may see here the granite raising up the strata, and bringing them to the light, where they appear on each side of those centrical ridges. What M. de la Metherie calls Monts Secondaires, I would call the proper strata of the globe, whether primary or secondary; and the Monts Granit, I would consider as mineral masses, which truly, or in a certain sense, are secondary, as having been made to invade, in a fluid state, the strata from below, when they were under water; and which masses had served to raise the country above the level of the ocean.

But this is not the subject here immediately under consideration; we are now tracing the operations of rivers upon the surface of the earth, in order to see in the present state of things a former state, and to explain the apparent irregularity of the surface and confusion of the various mineral bodies, by finding order in the works of nature; or a general system of the globe, in which the preservation of the habitable world is consulted.

For this last purpose also the mineral map of M. de la Metherie is valuable. It gives us a plan of the valleys of the great rivers, and their various branches, which, however infinitely ramified, may be considered as forming each one great valley watered, or rather drained, by its proper river. But the view I would now wish to take of those valleys, is that of habitable and fertile countries formed by the attrition of those rivers; and to perceive the operation of water wearing down the softer and less solid parts, while the more hard and solid rocks of the ridges, as well as scattered mountains, had resisted and preserved a higher station.

In this map, for example, let us suppose the first and second ridge of our author's plan to be joined at the mouth of the Loire, and retain the water of that river, as high as the summit of its surrounding ridges; this great valley of the Loire, which at present is so fine and fertile a country, would become a lake; in like manner as the proper valley of the Rhone, above St Maurice, would be drowned by shutting up that gap of the mountains through which the Rhone passes in order to enter the plain of Geneva.

This is the view that P. Chrysologue takes of those small valleys formed between the ridges of the Jura. But this is not perhaps the just view of the subject; for though by closing the gap by which the Loire or Rhone, passes through the inclosing ridge, the present country above would certainly be overflowed by the accumulated waters, yet it is more natural to suppose, that the great gap of the Loire, or the Rhone, had been formed gradually, in proportion as the inclosed country had been worn down and transported to the sea. We have but to consider, that the attrition of those transported materials must have been as necessary for the hollowing out of those gaps in the solid rock of the obstructing mountains, as the opening of those gaps may have been for the transporting of those materials to the sea. But it is perhaps impossible, from the present appearance of things, to see what revolutions may have happened to this country in the course of its degradation; what lakes may have been formed; what mountains of softer materials may have been levelled; and what basons of water filled up and obliterated.

This general view of the valley of the Loire, and all its branches, is perhaps too extensive to be admitted in this reasoning from effect to cause; we must approximate it by an intermediate step, which will easily be acknowledged as entering within the rule. It is in Forrez, near the head of the Loire. There we find the plain of Mont Brison, 40,000 toises or 22 miles long and half as wide, surrounded by a ridge of granite mountains on every side. Here the river, which is a small branch of the Loire, enters at the upper end of the plain (as M. de Bournon has described)[29] "Par une gorge tres etroite et tortueuse," and goes out in like manner at the under End.

[Footnote 29: Journal de Physique, Mai 1787.]

Those French philosophers, who have seen this plain, have little doubts of this having been a lake, that is to say, they easily admit of the original continuity of those ridges of mountains in which the gaps are now found, through which the river passes. But upon those principles it must be evident, that the river has hollowed out that plain, at the same time that it had formed the gaps in those ridges of the granite mountains. The only solid part, or original stratum, which M. de Bournon has described as having seen in this plain, is a decomposing gres or sandstone; but there is reason to suppose, that there had been both calcareous and argillaceous or marly strata filling the hollow of that space which is inclosed by the granite mountains; consequently, no difficulty in conceiving that the river, which must wear away a passage through those mountains, should also hollow out the softer materials within, and thus form the plain, or rather a succession of plains, in proportion as the level of the water had been lowered with the wearing mountains.

If we are allowed to make this step, which I think can hardly be refused, we may proceed to enlarge our view, by comprehending, first, the Vallais of the Rhone, secondly, the countries of the Seine and Rhone, above the mountains through which those two rivers in conjunction have broke, below Lyons; and, lastly, that country of the Rhone and Durance which is almost inclosed by the surrounding mountains, meeting at the mouth of the Rhone. But this reasoning will equally apply to the countries of the Garonne, the Loire, and the Seine.

One observation more may now be made with regard to the courses of great rivers, and the fertile countries which they form in depositing the travelled soil; it is this. That though those rivers have hollowed out their beds and raised their banks; though they are constantly operating in forming fertile soil in one place and destroying it in another; and though, in many particular situations, the fertile countries, formed at the mouths of those rivers, are visibly upon the increase, yet the general progress of those operations is so slow, that human history does not serve to give us information almost of any former state of things. The Nile will serve as an example of this fact.

The river Nile, which rises in the heights of Ethiopia, runs an amazing tract through desert countries, and discharges its waters near the bottom of the Mediterranean sea, fertilizes a long valley among barren countries with which it is surrounded, and thus lays the foundation of a kingdom, which, from its situation and the number of people it can maintain and easily bring together for any manner of action, is perhaps the strongest that can well be imagined. Accordingly, it has been of old a great kingdom, that is to say, a powerful state within itself; and has left monuments of this power, which have long been the admiration of the world. The most ancient Grecian Histories mention these monuments as being no better known, with regard to their dates and authors, than they are at this day.

The conclusion here meant to be drawn is this, that, in a period of time much more ancient than the most ancient periods in human history, Egypt had been a country formed and watered by the Nile in like manner as it is at present; that though continual changes are making in this as well as in every other river, yet, on the whole, no sensible alteration can be discerned within the compass of human experience, consequently, it is only by considering, in a scientific manner, the nature of things, and making allowances for operations which have taken place in time past, that any competent judgment can be formed of the present shape and condition of countries, or of any particular place upon the surface of this earth, so far as regards its date, its causes, or its future state. Nothing, almost, but the kingdom of Egypt would have formed those stupendous monuments of art and labour; and nothing but the present state of Egypt, fertilised by the Nile, could have formed that powerful kingdom which might execute those works.

Thus there is a system of mountains and valleys, of hills and plains, of rivulets and rivers, all of which are so perfectly connected, and so admirably proportioned, in their forms and quantities, like the arteries and veins of the animal body, that it would be absurd to suppose any thing but wisdom could have designed this system of the earth, in delivering water to run from the higher ground; or that any thing could have formed this beautiful disposition of things but the operation of the most steady causes; operations which, in the unlimited succession of time, has brought to our view scenes which seem to us to have been always, or to have been in the original construction of this earth.

To suppose the currents of the ocean to have formed that system of hill and dale, of branching rivers and rivulets, divided almost ad infinitum, which assemble together the water poured at large upon the surface of the earth, in order to nourish a great diversity of animals calculated for that moving element, and which carry back to the sea the superfluity of water, would be to suppose a systematic order in the currents of the ocean, an order which, with as much reason, we might look for, in the wind. The diversity of heights upon the surface of the earth, and of hardness and solidity in the masses of which the land is formed, is doubtless governed by causes proper to the mineral kingdom, and independent either of the atmosphere or sea; but the form and structure by which the surface of the earth is fitted peculiarly to the purpose of this living world, in giving a fertility which sustains both plants and animals, is only caused by those powers which work upon the surface of the earth,—those powers, the operation of which men in general see with indifference every day, sometimes with horror or apprehension.

The system of sustaining plants and animals upon a surface where fertility abounds, and where even the desert has its proper use, is to be perceived from the summit of the mountain to the shore within the region of the sea; and although we have principally taken the Alps, or alpine situations, for particular examples, in illustrating this operation of the waters upon the surface of the earth, it is because the effects are here more obvious to every inquirer, and not because there is here to be acknowledged any other principle than that which is to be found on all the surface of the earth, a principle of generation in one sense, and of destruction in another.

We may also find in this particular, a certain degree of confirmation to another part of the same theory; a part which does not come so immediately within our view, and concerning which so many contradictory hypotheses have been formed. Naturalists have supposed a certain original construction of mountains, which constitution of things, however, they never have explained; they have also distinguished those which have evidently been formed in another manner, that is to say, those the materials of which had been collected in the ocean. Now, here are two things perfectly different; on the one hand original mountains formed by nature, but we know not how, endued with solidity, but not differing in this respect from those of a posterior formation; on the other hand, secondary mountains, formed by the collection of materials in the sea, therefore, not having solidity as a quality inherent in their constitution, but only occasional or accidental in their nature. If, therefore, it be the natural constitution of things upon the surface of this earth to indurate and become solid, however originally formed loose and incoherent, we should thus find an explanation of the consolidation of those masses which had been lately formed of the loose materials of the ocean; if, on the contrary, we find those pretended primitive mountains, those bodies which are endued with hardness and solidity, wasting by the hand of time, and thus wearing in the operations natural to the surface of the earth, Where shall we find the consolidating operations, those by which beds of shells have been transformed into perfect marble, and siliceous bodies into solid flint? or how reconcile those opposite intentions in the same cause?

Nothing can be more absurd than to suppose a collection of shells and corals, amassed about the primitive mountains of the earth, to become mountains equally solid with the others, upon the removal of the sea; it would be inconsistent with every principle of sound reasoning to suppose those masses of loose materials to oppose equal resistance to the wasting and destroying operations of the surface of the earth, as do those pretended primitive masses, which might be supposed endued with natural hardness and solidity; yet, consult the matter of fact, and it does not appear that there is any difference to be perceived. There are lofty mountains to be found both of the one kind and the other; both those different masses yield to the wasting operations of the surface; and they are both carried away with the descending waters of the earth.

It is not here meant to affirm, that a mass of marble, which is a calcareous substance, opposes equal resistance, whether to the operations of dissolution or attrition, as a mass composed of granite or of quartz; it is only here maintained that there are in the Alps lofty mountains of marble, as there are in other places lower masses of granite and its accompanying schistus. But that which is particularly to be attended to here is this: In all countries of the earth, whether of primitive masses or those of secondary formation, whether uniform and homogeneous, or compound and mixed of those two different kinds of bodies, the system is always the same, of hills and valleys, lakes and rivers, ravines and streams: no man can say, by looking into the most perfect map, what is primary or what secondary in the constitution of the globe. It is the same system of larger rivers branching into lesser and lesser in a continued series, of smaller rivers in like manner branching into rivulets, and of rivulets terminating at last into springs or temporary streams. The principle is universal; and, having learned the natural history of one river, we know the constitution of every other upon the face of the earth.

Thus all the surface of this earth is formed according to a regular system of heights and hollows, hills and valleys, rivulets and rivers, and these rivers return the waters of the atmosphere into the general mass, in like manner as the blood, returning to the heart, is conducted in the veins. But as the solid land, formed at the bottom of the sea or in the bowels of the earth, could not be there constructed according to that system of things which we find so widely pursued upon the surface of the globe, it must be by wasting the solid parts of the land that this system of the surface has been formed, in like manner as it is by the operations of the sea that the shape of the land is determined, upon the shore.

Thus it has been shown, that the general tendency of the operations natural to the surface of the globe is to wear the surface of the earth, and waste the land; consequently that, however long the continents of this earth may be supposed to last, they are on the whole in a constant state of diminution and decay; and, in the progress of time, will naturally disappear. Hence confirmation is added to that mineral system of the earth, by which the present land is supposed to have acquired solidity and hardness; and according to which future land is supposed to be preparing from the materials of the sea and former continents; which land will be brought to light in time, to supply the place of that which necessarily wastes, in serving plants and animals. But what is here more particularly to the purpose is this; that we find an explanation of that various shape and conformation which is to be observed upon the surface of this earth, as being the effect of causes which are constant and unremitting in their operation, which are widely adapted to the end or absolutely necessary in the system of this world, and which, in the indefinite course of time, become unlimited in their effect, or powerful in any conceivable degree.

It is not sufficient for establishing the present theory, to refute that most unscientific hypothesis, adopted by some eminent philosophers, of mountains and valleys being the effect of currents in the ocean; it is necessary to see what is their proper cause, and to show that by no other cause known could the general effect, which is of such importance in the system of this world, be actually produced. It is for this reason that we have endeavoured to show that there is a general, an universal system of river and valley, which renders the surface of this earth a sort of organized body destined to a purpose which it perfectly fulfils.

But to see the full force of this argument, taken from that order of things which is perceived in that system of valley and river all over the earth, let us examine, first, what would be the effect, in the constitution of this world, of bodies of land formed upon no such system; and, secondly, what would be the effect of the natural constitution of this world and meteorological operations of the atmosphere, if continued for a sufficient length of time, upon a mass of land without any systematic form.

For this purpose we shall take for example a portion of this earth, which is the best known to us, that is the south-western part of Europe, in order to compare its present state, which so perfectly fulfils the purpose of this world, with that in which no order of valley and of rivers should be fund.

Let us begin at the summit, which is the Mont-Blanc. At present the water, falling from the heavens upon this continent, is gathered into a system of rivers which run through valleys, and is delivered at last into the Adriatic, the Mediterranean, the Atlantic, and the German Seas; all the rest of this continent, except some lakes and marshes, is dry land, properly calculated, for the sustenance of a variety of plants and animals, and so fulfils the purpose of a habitable earth. Now, destroy that system of river and valley, and the whole would become a mixture of lakes and marshes, except the summits of a few barren rocks and mountains. No regular channels for conveying the super-abundant water being made, every thing must be deluged, and nothing but a system of aquatic plants and animals appear. A continent of this sort is not found upon the globe; and such a constitution of things, in general, would not answer the purpose of the habitable world which we possess. It is therefore necessary to modify the surface of such a continent of land, as had been formed in the sea, and produced, by whatever means, into the atmosphere for the purpose of maintaining that variety of plants and animals which we behold; and now we are to examine how far the proper means for that modification is to be found necessarily in the constitution of this world.

If we consider our continent as composed of such materials as may decay by the influence of the atmosphere, and be moved by water descending from the higher to the lower ground, as is actually the case with the land of our globe, then the water would gradually form channels in which it would run from place to place; and those channels, continually uniting as they proceed to the sea or shore, would form a system of rivers and their branchings. But this system of moving water must gradually produce valleys, by carrying away stones and earthy matter in their floods; and those valleys would be changing according to the softness, and hardness, destructability or indestructability of the solid parts below. Still however the system of valley and river would be preserved; and to this would be added the system of mountains, and valleys, of hills and plains, to the formation of which the unequal wearing down of the solids must in a great measure contribute.

Here therefore it is evident, first, that the great system upon the surface of this earth, is that of valleys and rivers; secondly, that no such system could arise from the operations of the sea when covering the nascent land; thirdly, that this system is accomplished by the same means which, are employed for procuring soil from the decaying rocks and strata; and, lastly, that however this system shall be interrupted and occasionally destroyed, it would necessarily be again formed in time, while the earth continued above the level of the sea. Whatever changes take place from the operation of internal causes, the habitable earth, in general, is always preserved with the vigour of youth, and the perfection of the most mature age. We cannot see man cultivate the field, without perceiving that system of dry land provided by nature in forming valleys and rivers; we cannot study the rocks and solid strata of the earth, those bulwarks of the field and shore, without acknowledging the provident design of nature in giving as much permanency to our continent, as is consistent with sufficient fertility; and we cannot contemplate the necessary waste of a present continent, without perceiving the means for laying the foundation of another. But the evidence of those truths is not open to a vulgar view; media are required, or much reasoning; and between the first link and the last, in this chain, what a distance, from the wasting of hard bodies upon the surface of the earth, to the formation of a solid rock at the bottom of the sea.



CHAP. XIV.

Summary of the Doctrine which has been now Illustrated.

The system of this earth appears to comprehend many different operations; and it exhibits various powers co-operating for the production of those effects which we perceive. Of this we are informed by studying natural appearances; and in this manner we are led to understand the nature of things, in knowing causes.

That our land, which is now above the level of the sea, had been formerly under water, is a fact for which there is every where the testimony of a multitude of observations. This indeed is a fact which is admitted upon all hands; it is a fact upon which the speculations of philosophers have been already much employed; but it is a fact still more important, in my opinion, than it has been ever yet considered. It is not, however, as a solitary fact that any rational system may be founded upon this truth, That the earth had been formerly at the bottom of the sea; we must also see the nature and constitution of this earth as necessarily subsisting in continual change; and we must see the means employed by nature for constructing a continent of solid land in the fluid bosom of the deep. It is then that we may judge of that design, by finding ends and means contrived in wisdom, that is to say, properly adapted to each other.

We have now given a theory founded upon the actual state of this earth, and the appearances of things, so far as they are changing; and we have, in support of that theory, adduced the observations of scientific men, who have carefully examined nature and described things in a manner that is clear and intelligible. We are now to take a review of the principle points on which this theory hangs; and to endeavour to point out the importance of the subject, and the proper manner of judging with regard to a theory of the earth, how far it is conform to the general system of nature, which has for object a world.

If it should be admitted, that this earth had been formed by the collection of materials deposited within the sea, there will then appear to be certain things which ought to be explained by a theory, before that theory be received as belonging to this earth. These are as follows:

First, We ought to show how it came about that this whole earth, or by far the greatest part in all the quarters of the globe, had been formed of transported materials collected together in the sea. It must be here remembered, that the highest of our mountainous countries are equally formed of those travelled materials as are the lowest of our plains; we are not therefore to have recourse to any thing that we see at present for the origin of those materials which actually compose the earth; and we must show from whence had come those travelled materials, manufactured by water, which were employed in composing the highest places of our land.

Secondly, We must explain how those loose and incoherent materials had been consolidated, as we find they are at present. We are not here to allow ourselves the liberty, which naturalists have assumed without the least foundation, of explaining every thing of this sort by infiltration, a term in this case expressing nothing but our ignorance.

Thirdly, The strata are not always equally consolidated. We often find contiguous strata in very different states with respect to solidity; and sometimes the most solid masses are found involved in the most porous substance. Some explanation surely would be expected for this appearance, which is of a nature so conclusive as ought to attract the attention of a theorist.

Fourthly, It is not sufficient to show how the earth in general had been consolidated; we must also explain, how it comes to pass that the consolidated bodies are always broken and intersected by veins and fissures. In this case, the reason commonly given, that the earth exposed to the atmosphere had shrunk like moist clay, or contracted by the operation of drying, can only show that such naturalists have thought but little upon the subject. The effect in no shape or degree corresponds to that cause; and veins and fissures, in the solid bodies, are no less frequent under the level of the sea, than on the summits of our mountains.

Fifthly, Having found a cause for the fracture and separation of the solid masses, we must also tell from whence the matter with which those chasms are filled, matter which is foreign both to the earth and sea, had been introduced into the veins that intersect the strata. If we fail in this particular, What credit could be given to such hypotheses as are contrived for the explanation of more ambiguous appearances, even when those suppositions should appear most probable?

Sixthly, Supposing that hitherto every thing had been explained in the most satisfactory manner, the most important appearances of our earth still remain to be considered. We find those strata that were originally formed continuous in their substance, and horizontal in their position, now broken, bended, and inclined, in every manner and degree; we must give some reason in our theory for such a general changed state and disposition of things; and we must tell by what power this event, whether accidental or intended, had been brought about.

Lastly, Whatever powers had been employed in preparing land, while situated under water, or at the bottom of the sea, the most powerful operation yet remains to be explained; this is the means by which the lowest surface of the solid globe was made to be the highest upon the earth. Unless we can show a power of sufficient force, and placed in a proper situation for that purpose, our theory would go for nothing, among people who investigate the nature of things, and who, founding on experience, reason by induction from effect to cause.

Nothing can be admitted as a theory of the earth which does not, in a satisfactory manner, give the efficient causes for all these effects already enumerated. For, as things are universally to be acknowledged in the earth, it is essential in a theory to explain those natural appearances.

But this is not all. We live in a world where order every where prevails; and where final causes are as well known, at least, as those which are efficient. The muscles, for example, by which I move my fingers when I write, are no more the efficient cause of that motion, than this motion is the final cause for which the muscles had been made. Thus, the circulation of the blood is the efficient cause of life; but, life is the final cause, not only for the circulation of the blood, but for the revolution of the globe: Without a central luminary, and a revolution of the planetary body, there could not have been a living creature upon the face of this earth; and, while we see a living system on this earth, we must acknowledge, that in the solar system we see a final cause.

Now, in a theory which considers this earth as placed in a system of things where ends are at least attained, if not contrived in wisdom, final causes must appear to be an object of consideration, as well as those which are efficient. A living world is evidently an object in the design of things, by whatever Being those things had been designed, and however either wisdom or folly may appear in that design. Therefore the explanation, which is given of the different phenomena of the earth, must be consistent with the actual constitution of this earth as a living world, that is, a world maintaining a system of living animals and plants.

Not only are no powers to be employed that are not natural to the globe, no action to be admitted of except those of which we know the principle, and no extraordinary events to be alledged in order to explain a common appearance, the powers of nature are not to be employed in order to destroy the very object of those powers; we are not to make nature act in violation to that order which we actually observe, and in subversion of that end which is to be perceived in the system of created things. In whatever manner, therefore, we are to employ the great agents, fire and water, for producing those things which appear, it ought to be in such a way as is consistent with the propagation of plants and life of animals upon the surface of the earth. Chaos and confusion are not to be introduced into the order of nature, because certain things appear to our partial views as being in some disorder. Nor are we to proceed in feigning causes, when those seem insufficient which occur in our experience.

Animal life being thus considered as an object in the view of nature, we are to consider this earth as being the means appointed for that end; and then the question is suggested, How far wisdom may appear in the constitution of this earth, as being means properly adapted to the system of animal life, which is evidently the end. This is taking for granted, that there is a known system of the earth which is to be tried—how far properly adapted to the end intended in nature. But, it is this very system of the earth which is here the subject of investigation; and, it is in order to discover the true system that we are to examine, by means of final causes, every theory which pretends to show the nature of that system, or to assign efficient causes to physical events.

Here then we have a rule to try the propriety of every operation which should be acknowledged as in the system of nature, or as belonging to the theory of this earth. It is not necessary that we should see the propriety of every natural operation; our natural ignorance precludes us from any title to form a judgment in things of which we are not properly informed; but, no suppositions of events, or explanations of natural appearances, are to be admitted into our Theory, if the propriety of those alledged operations is not made to appear. We are now to make an application.

This earth, which is now dry land, was under water, and was formed in the sea. Here is a matter of fact, and not of theory, so far as it can be made as evident as any thing of which we have not seen the immediate act or execution. But the propriety of this matter of fact is only to be perceived in making the following acknowledgment, That the origin of this earth is necessarily placed in the bottom of the sea. In supposing any other origin to this habitable earth, we would see the impropriety of having it covered with water, or drowned in the sea. But, being formed originally at the bottom of the sea, if we can explain the phenomena of this earth by natural causes, we will acknowledge the wisdom of those means, by which the earth, thus formed at the bottom of the sea, had been perfected in its nature, and made to fulfil the purpose of its intention, by being placed in the atmosphere.

If the habitable earth does not take its origin in the waters of the sea, the washing away of the matter of this earth into the sea would put a period to the existence of that system which forms the admirable constitution of this living world. But, if the origin of this earth is founded in the sea, the matter which is washed from our land is only proceeding in the order of the system; and thus no change would be made in the general system of this world, although this particular earth, which we possess at present, should in the course of nature disappear.

It has already been our business to show that the land is actually wasted universally, and carried away into the sea. Now, What is the final cause of this event?—Is it in order to destroy the system of this living world, that the operations of nature are thus disposed upon the surface of this earth? Or, Is it to perpetuate the progress of that system, which, in other respects, appears to be contrived with so much wisdom? Here are questions which a Theory of the Earth must solve; and here indeed, must be found the most material part by far of any Theory of the Earth. For, as we are more immediately concerned with the operations of the surface, it is the revolutions of that surface which forms, for us, the most interesting subject of inquiry.

Thus we are led to inquire into the final cause of things, while we investigate an operation of such magnitude and importance, as is that of forming land of sea, and sea of land, of apparently reversing nature, and of destroying that which is so admirably adapted to its purpose. Was it the work of accident, or effect of an occasional transaction, that by which the sea had covered our land? Or, Was it the intention of that Mind which formed the matter of this globe, which endued that matter with its active and its passive powers, and which placed it with so much wisdom among a numberless collection of bodies, all moving in a system? If we admit the first, the consequence of such a supposition would be to attribute to chance the constitution of this world, in which the systems of life and sense, of reason and intellect, are necessarily maintained. If again we shall admit, that there is intention in the cause by which the present earth had been removed from the bottom of the sea, we may then inquire into the nature of that system in which a habitable earth, possessed of beauty, arranged in order, and preserved with economy, had been formed by the mixture and combination of the different elements, and made to rise out of the wreck of a former world.

In examining the structure of our earth, we find it no less evidently formed of loose and incoherent materials, than that those materials had been collected from different parts, and gathered together at the bottom of the sea. Consequently, if this continent of land, first collected in the sea, and then raised above its surface, is to remain a habitable earth, and to resist the moving waters of the globe, certain degrees of solidity or consolidation must be given to that collection of loose materials; and certain degrees of hardness must be given to bodies which were soft or incoherent, and consequently so extremely perishable in the situation where they now are placed.

But, at the same time that this earth must have solidity and hardness to resist the sudden changes which its moving fluids would occasion, it must be made subject to decay and, waste upon the surface exposed to the atmosphere; for, such an earth as were made incapable of change, or not subject to decay, could not afford that fertile soil which is required in the system of this world, a soil on which depends the growth of plants and life of animals,—the end of its intention.

Now, we find this earth endued precisely with that degree of hardness and consolidation, as qualifies it at the same time to be a fruitful earth, and to maintain its station with all the permanency compatible with the nature of things, which are not formed to remain unchangeable.

Thus we have a view of the most perfect wisdom, in the contrivance of that constitution by which the earth is made to answer, in the best manner possible, the purpose of its intention, that is, to maintain and perpetuate a system of vegetation, or the various race of useful plants, and a system of living animals, which are in their turn subservient to a system still infinitely more important, I mean, a system of intellect. Without fertility in the earth, many races of plants and animals would soon perish, or be extinct; and, without permanency in our land, it were impossible for the various tribes of plants and animals to be dispersed over all the surface of a changing earth. The fact is, that fertility, adequate to the various ends in view, is found in all the quarters of the world, or in every country of the earth; and, the permanency of our land is such, as to make it appear unalterable to mankind in general, and even to impose upon men of science, who have endeavoured to persuade us that this earth is not to change. Nothing but supreme power and wisdom could have reconciled those two opposite ends of intention, so as both to be equally pursued in the system of nature, and both so equally attained as to be imperceptible to common observation, and at the same time a proper object for the human understanding.

We thus are led to inquire into the efficient causes of this constitution of things, by which solidity and stability had been bestowed upon a mass of loose materials, and by which this solid earth, formed first at the bottom of the sea, had been placed in the atmosphere, where plants and animals find the necessary conditions of their life.

Now, we have shown, that subterraneous fire and heat had been employed in the consolidation of our earth, and in the erection of that consolidated body into the place of land. The prejudices of mankind, who cannot see the steps by which we come at this conclusion, are against the doctrine; but, prejudice must give way to evidence. No other Theory will in any degree explain appearances, while almost every appearance is easily explained by this Theory.

We do not dispute the chymical action and efficacy of water, or any other substance which is found among the materials collected at the bottom of the sea; we only mean to affirm, that every action of this kind is incapable of producing perfect solidity in the body of earth in that situation of things, whatever time should be allowed for that operation, and that whatever may have been the operations of water, aided by fire, and evaporated by heat, the various appearances of mineralization, (every where presented to us in the solid earth, and the most perfect objects of examination), are plainly inexplicable upon the principle of aqueous solution. On the other hand, the operation of heat, melting incoherent bodies, and introducing softness into rigid substances which are to be united, is not only a cause which is proper to explain the effects in question, but also appears, from a multitude of different circumstances, to have been actually exerted among the consolidated bodies of our earth, and in the mineral veins with which the solid bodies of the earth abound.

The doctrine, therefore, of our Theory is briefly this, That, whatever may have been the operation of dissolving water, and the chymical action of it upon the materials accumulated at the bottom of the sea, the general solidity of that mass of earth, and the placing of it in the atmosphere above the surface of the sea, has been the immediate operation of fire or heat melting and expanding bodies. Here is a proposition which may be tried, in applying it to all the phenomena of the mineral region; so far as I have seen, it is perfectly verified in that application.

We have another proposition in our Theory; one which is still more interesting to consider. It is this, That as, in the mineral regions, the loose or incoherent materials of our land had been consolidated by the action of heat; so, upon the surface of this earth exposed to the fluid elements of air and water, there is a necessary principle of dissolution and decay, for that consolidated earth which from the mineral region is exposed to the day. The solid body being thus gradually impaired, there are moving powers continually employed, by which the summits of our land are constantly degraded, and the materials of this decaying surface travelled towards the coast. There are other powers which act upon the shore, by which the coast is necessarily impaired, and our land subjected to the perpetual incroachment of the ocean.

Here is a part of the Theory with which every appearance of the surface may be compared. I am confident that it will stand the test of the most rigid examination; and that nothing but the most inconsiderate judgment may mistake a few appearances, which, when properly understood, instead of forming any subject of objection to the Theory, will be found to afford it every reasonable support or confirmation.

We have now seen, that in every quarter of the globe, and in every climate of the earth, there is formed, by means of the decay of solid rocks, and by the transportation of those moveable materials, that beautiful system of mountains and valleys, of hills and plains, covered with growing plants, and inhabited by animals. We have seen, that, with this system of animal and vegetable economy, which depends on soil and climate, there is also a system of moving water, poured upon the surface of the earth[30], in the most beneficial manner possible for the use of vegetation, and the preservation of our soil; and that this water is gathered together again by running to the lowest place, in order to avoid accumulation of water upon the surface, which would be noxious.

[Footnote 30: See Dissertations upon Subjects of Natural Philosophy, Part I.]

It is in this manner that we first have streams or torrents, which only run in times of rain. But the rain-water absorbed into the earth is made to issue out in springs, which run perpetually, and which, gathering together as they run, form rivulets, watering valleys, and delighting the various inhabitants of this earth. The rivulets again are united in their turn, and form those rivers which overflow our plains, and which alternately bring permanent fertility and casual devastation to our land. Those rivers, augmenting in their volume as they unite, pour at last their mighty waters into the ocean; and thus is completed that circulation of wholesome fluids, which the earth requires in order to be a habitable world.

Our Theory farther shows, that in the ocean there is a system of animals which have contributed so materially to the formation of our land. These animals are necessarily maintained by the vegetable provision, which is returned in the rivers to the sea, and which the land alone or principally produces. Thus we may perceive the mutual dependence upon each other of those two habitable worlds,—the fluid ocean and the fertile earth.

The land is formed in the sea, and in great part by inhabitants of that fluid world. But those animals, which form with their exuviae such a portion of the land, are maintained, like those upon the surface of the earth, by the produce of that land to which they formerly had contributed. Thus the vegetable matter, which is produced upon the surface of the earth in such abundance for the use of animals, and which, in such various shapes, is carried by the rivers into the sea, there sustains that living system which is daily employed to make materials for a future land.

Here is a compound system of things, forming together one whole living world; a world maintaining an almost endless diversity of plants and animals, by the disposition of its various parrs, and by the circulation of its different kinds of matter. Now, we are to examine into the necessary consequence of this disposition of things, where the matter of this active world is perpetually moved, in that salutary circulation by which provision is so wisely made for the growth and prosperity of plants, and for the life and comfort of its various animals.

If, in examining this subject, we shall find that there is nothing in the system but what is necessary, that is, nothing in the means employed but what the importance of the end requires; if we shall find that the end is steadily pursued, and that there is no deficiency in the means which are employed; and if it shall be acknowledged that the end which is attained is not idle or insignificant, we then may draw this conclusion, That such a system is in perfect wisdom; and therefore that this system, so far as it is found corresponding properly with natural appearances, is the system of nature, and not the creature of imagination.

Let us then take a cursory view of this system of things, upon which we have proceeded in our theory, and upon which the constitution of this world seems to depend.

Our solid earth is every where wasted, where exposed to the day. The summits of the mountains are necessarily degraded. The solid and weighty materials of those mountains are every where urged through the valleys, by the force of running water. The soil, which is produced in the destruction of the solid earth, is gradually travelled by the moving water, but is constantly supplying vegetation with its necessary aid. This travelled soil is at last deposited upon the coast, where it forms most fertile countries. But the billows of the ocean agitate the loose materials upon the shore, and wear away the coast, with the endless repetitions of this act of power, or this imparted force. Thus the continent of our earth, sapped in its foundation, is carried away into the deep, and sunk again at the bottom of the sea, from whence it had originated.

We are thus led to see a circulation in the matter of this globe, and a system of beautiful economy in the works of nature. This earth, like the body of an animal, is wasted at the same time that it is repaired. It has a state of growth and augmentation; it has another state, which is that of diminution and decay. This world is thus destroyed in one part, but it is renewed in another; and the operations by which this world is thus constantly renewed, are as evident to the scientific eye, as are those in which it is necessarily destroyed. The marks of the internal fire, by which the rocks, beneath the sea are hardened, and by which the land is produced above the surface of the sea, have nothing in them which is doubtful or ambiguous. The destroying operations again, though placed within the reach of our examination, and evident almost to every observer, are no more acknowledged by mankind, than is that system of renovation which philosophy alone discovers.

It is only in science that any question concerning the origin and end of things is formed; and it is in science only that the resolution of those questions is to be attained. The natural operations of this globe, by which the size and shape of our land are changed, are so slow as to be altogether imperceptible to men who are employed in pursuing the various occupations of life and literature. We must not ask the industrious inhabitant, for the end or origin of this earth: he sees the present, and he looks no farther into the works of time than his experience can supply his reason. We must not ask the statesman, who looks into the history of time past, for the rise and fall of empires; he proceeds upon the idea of a stationary earth, and most justly has respect to nothing but the influence of moral causes.

It is in the philosophy of nature that the natural history of this earth is to be studied; and we must not allow ourselves ever to reason without proper data, or to fabricate a system of apparent wisdom in the folly of a hypothetical delusion.

When, to a scientific view of the subject, we join the proof which has been given, that in all the quarters of the globe, in every place upon the surface of the earth, there are the most undoubted marks of the continued progress of those operations which wear away and waste the land, both in its height and width, its elevation and extention, and that for a space of duration in which our measures of time are lost, we must sit down contented with this limitation of our retrospect, as well as prospect, and acknowledge, that it is in vain to seek for any computation of the time, during which the materials of this earth had been prepared in a preceding world, and collected at the bottom of a former sea.

The system of this earth will thus appear to comprehend many different operations, or it exhibits various powers co-operating for the production of those appearances which we properly understand in knowing causes. Thus, in order to understand the natural conformation of this country, or the particular shape of any other place upon the globe, it is not enough to see the effects of those powers which gradually waste and wear away the surface, we must also see how those powers affecting the surface operate, or by what principle they act.

Besides, seeing those powers which are employed in thus changing the surface of the earth, we must also observe how their force is naturally augmented with the declivity of the ground on which they operate. Neither is it sufficient to understand by what powers the surface is impaired, for, it may be asked, why, in equal circumstances, one part is more impaired than another; this then leads to the examination of the mineral system, in which are determined the hardness and solidity, consequently, the permanency of those bodies of which our land is composed; and here are sources of indefinite variety.

In the system of the globe every thing must be consistent. The changing and destroying operations of the surface exposed to the sun and influences of the atmosphere, must correspond to those by which land is composed at the bottom of the sea; and the consolidating operations of the mineral region must correspond to those appearances which in the rocks, the veins, and solid stones, give such evident, such universal testimony of the power of fire, in bringing bodies into fusion, or introducing fluidity, the necessary prelude to solidity and concretion.

Those various powers of nature have thus been employed in the theory, to explain things which commonly appear; or rather, it is from things which universally appear that causes have been concluded, upon scientific principles, for those effects. A system is thus formed, in generalising all those different effects, or in ascribing all those particular operations to a general end. This end, the subject of our understanding, is then to be considered as an object of design; and, in this design, we may perceive, either wisdom, so far as the ends and means are properly adapted, or benevolence, so far as that system is contrived for the benefit of beings who are capable of suffering pain and pleasure, and of judging good and evil.

But, in this physical dissertation, we are limited to consider the manner in which things present have been made to come to pass, and not to inquire concerning the moral end for which those things may have been calculated. Therefore, in pursuing this object, I am next to examine facts, with regard to the mineralogical part of the theory, from which, perhaps, light may be thrown upon the subject; and to endeavour to answer objections, or solve difficulties, which may naturally occur from the consideration of particular appearances.



END OF VOLUME SECOND.