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The formation of the beds or strata, by a suc rests, we are told that it will be followed by cessive deposition from water, would lead us to a similar renovation. Thus, as one continent de expect that the separate layers should be disposed scends another rises, like the opposite scales of a horizontally, or that they should, in their whole balance; and, in the resources of the system, that extent, be arranged at right angles to the force of order of organic nature is supposed to be traced gravity; that they should be continuous or with- by which the continued existence of the different out fissures; and that they should have no ele races is secured, not by the perpetuity of the invations or depressions. The reverse of this, dividual, but by the successive re-production of however, is the fact. Instead of universal hori- the kind. Our present world is thus one in an zontality, we frequently find them almost in a indefinite series of worlds which have existed in vertical position; instead of a continuous surface, times past, and which are destined in future to hke the coats of an onion, we see wide irregular appear; and all the less obvious or more striking rents and fissures; and, instead of a uniformly changes which we witness are steps in the prolevel appearance, we find mountains and alpine gress of mighty revolutions, to which the imagichains shooting up many thousand feet above nation can set no limits, either with regard to their surrounding regions. In a system that lays duration or magnitude. claim to consistency, some explanation must be He lays down as a certain position, that the provided for reconciling these apparent anoma solid parts of our earth are suffering decay from lies with its general principles, and many sup- the action of the elements; that the portions depositions may obviously be resorted to. The tached from the more elevated ground are carried greatest inequalities of the earth's surface must by the operation of water to the lower levels, and have originated in the manner in which the ultimately deposited in the basin of the ocean. primitive strata assumed the crystalline appear. He conceives, that tides and currents there arance, and the circumstances under which chemi- range what is carried within their influence in cal affinities acted upon the materials of the layers along the bottom of the sea. This opechaotic fluid. The irregularities of the subse- ration must proceed very slowly, but Dr. Hution quent depositions may be partly owing to the is not limited with respect to time, and can kind of surface or bed on which they were make as large a use of it as his system demands. arranged, and partly to an unequal subsidence Every river, every brook, every stream of water in the contiguous parts deposited at the same that we see, descends towards the ocean, charged time. Many rents, fissures, and dislocations, with some portions of the surface over which it must have originated in the different degrees of flows. All the soil and softer parts on which solidity in the contiguous strata, in the unequal our plants are produced, have been confessedly weight which crystallisation imposed upon them, loosened by water, and may be ultimately transin the withdrawing of the water sooner or later ported by it to the lowest levels of the same elefrom different portions, and in several other causes, ment. The strata of our dry land have all been which it is unnecessary, in this short sketch, to thus carried from a pre-existing one, and arranged enumerate. Many of these rents and fissures by the ocean which then covered it. were made while the strata were still immersed For their consolidation and other appearances, in the waters, and, being filled up with precipi- a new principle is assumed by the Huttonian tates of a more crystalline kind, constitute what geologists, which forms the chief characteristic are demominated veins, those repositories of of their system. They conceive that there permineral wealth. The structure of veins, narrowing petually exists in the heart of the mineral kingin diameter as we descend, and the more regular dom an immense force of heat that has been sufdisposition of their contents, according to laws ficient to fuse or to soften the various strata of of chemical attraction, are offered as decided which its crust is composed. The greater or less proofs, both of their being filled by infiltration degree of liquidity which it thus produced, from above, and of their consolidation taking allowed the substances on which it acted to be place in circumstances where the mass suffered consolidated upon cooling, either into crystalline no disturbance.
fossils, or into less regular masses. The strata After this statement of the Wernerian theory, that were arranged at the bottom of the ocean, it might be proper to adduce some of the argu- from the debris of a former world, were thus ments that tend to confirm it, and some of the brought from their soft state of simple mechanical objections to which it has been thought liable; aggregation, to assume the compact structure of but both these will be more duly appreciated, mountain rocks. To this powerful agent of inafter we have drawn a similar outline of the rival ternal heat, is not only assigned the office of first system to which it is opposed.
softening and finally indurating the strata, but Dr. Hutton does not go back to chaos to lay that likewise of elevating them from the bottom the foundation of his habitable world, nor does of the sea, and converting them into dry land. he borrow much assistance in constructing his The strata at the bottom of the ocean, being fabric from chemical attractions. He rests upon arranged by water, must, it is conceived, have a pre-existing continent, out of the ruins of which been arranged in a horizontal direction, though our present dry land was formed and arranged now their appearance is extremely different. principally by mechanical means. The portion Their present fragmented and shattered surface, of the globe which we now possess was, accord- their deep chasms, their apparently ruinous coning to his hypothesis, the bottom of the sea when tortions and dislocations, the vertical position of the older continent was decaying to form it; this some of them, and the considerazle declination older contine was then, of course, immersed; of almost all, are also accounted for by the opeand, lest we should be alarmed at the recurrence ration of internal fire. . of a similar catastrophe to this scene of our inte The volatile ingredients of many bodies are
easily dissipated by caloric, and some com- history of the formation of the strata, as in his pounds are discovered in the mineral kingdom, system the strata were deposited and arranged which must have been exposed, upon this hypo- prior to the operation of fire upon them, and thesis, to such an intensity of heat as would have prior likewise to the existence of the more cryseffected a dissolution among their parts. To ob tallised masses formed by fusion. With the mode viate objections of this kind, the modification of of forming the stratified structure he therefore the effects of heat from the pressure under which begins his system ; and here likewise begin the it acts, is illustrated and applied with great inge- objections to which it has been thought liable. nuity. This modification of heat, by pressure, He supposes that the materials of all the strata is a very important fact to the Plutonian theory. are the debris of a pre-existing world ; that they
With regard to the order of time, or the suc- have been detached from it by the operation of cession in which the different rocks were formed the elements; carried, by the agency of water, that compose the crust of our earth, the Huttonian to the ocean; and there spread in regular order differs as much from the Wernerian as in the agent over its bottom by the same power. Thus all he principally employs. It will be remembered the rocks that exhibit the stratified structure, are that Werner calls granite the earliest of the pri- nothing but mechanical deposits, and rivers have mitive rocks, from the supposition that it was been the great agents in conveying them to their separated from the chaos by crystalline precipi- present situation. Now it cannot fail to strike tation, prior to the existence of any other mine- every one, that effects are here attributed to those ral. Dr. Hutton, on the contrary, in his chrono- streams that mark the surface of our globe, which logy of the fossil kingdom, places granite among they seem inadequate to produce. It is true that its last formed products, and brings forward its most rivers flow towards the ocean, charged with appearance as a triumphant proof of the truth of a part of the soil or softer rock which border his system. He conceives it in a state of fusion their channels; but it is not so true that they to have burst the superior strata with which it carry this burden to their ultimate destination. was enveloped, aided by the expansive power of A great part of it is deposited on their banks, or his central fire, and to have issued forth from its in the hollows of their courses, and much of what confined furnace somewhat in the manner of a reaches the sea goes to form bars, or, being stream of lava from a volcano. The greatest driven back to the shore, makes an addition to heights of our globe, and the most extensive the sea-coast. It is evident that a small portion mountain ranges, are thus nothing else but the only can reach the ocean, and if the disintegraconsolidated torrents of mighty eruptions, the tion be so slow as is admitted,' observes Mr. matter of which had been rendered liquid by a Murray; 'if, as Dr. Hutton himself observes, subterranean fire, which still exists for the future the description which Polybius has given of the accomplishment of similar effects, and gives Pontus Euxinus, with the two opposite Bosphori, proofs of present activity in the phenomena the Mæotis, the Propontis, and the port of Byof the volcano. To its complete fusion is zantium, is as applicable to the present state of ascribed its perfect crystalline texture, its want things as it was at the writing of that history; of stratification, and its perfect freedom from if the Isthmus of Corinth is apparently the organic remains.
at present as it was 2000 or 3000 A similar account is given by this system of years ago; if Scylla and Charybdis remain now the formation of veins, and of the fossils which as they were in ancient times, rocks hazardgenerally fill them. They are rents caused by a ous for coasting vessels; if the port of Syracuse, force acting from beneath, and filled with matters with the island which forms the greater and injected into them from the same quarter in a less, and the fountain of Arethusa, the water of state of fusion. Their contents are thus different which the ancients divided from the sea with a from the materials of the strata which they tra- wall, do uot seem to be altered ; and if, on the verse, and almost always present a highly crys- coast of Egypt, we find the rock on which was talline structure.
formerly built the famous tower of Pharos ; and, Such is the outline of the Huttonian theory of at the eastern extremity of the port Eunoste, the the earth, as far as regards the manner in which sea-bath cut in the solid rock on the shore, to all its crust was stratified in the bottom of the ocean, appearance the same at this day as they were in consolidated into a compact mass, elevated into ancient times : if such be the extreme slowness islands and continents, separated into distinct of the disintegration, the reflection is obvious, portions by veins and beds, and deranged in its that, admitting it, a duration will be allowed to horizontal appearances by an eruptive force. It the world infinitely beyond our conception, and is needless to mention the account which the adequate to any purpose which we can conceive supporters of this geological system give of vol- it designed to serve; and there is at least no canoes. They accord with their opinions, or necessity pointed out for supposing an arrangeperhaps suggested them; and the Wernerian ment by which it is to be perpetuated or restored. leaves them in full possession of such ground • Neither are the facts conclusive which are without reluctance, satisfied that the central heat, stated by Dr. Hutton and Mr. Playfair, to prove which raised continents, is not necessary to ex that all our strata have originated from the waste plain their phenomena.
of a former world, for they are equally well acAfter giving a very imperfect account of these counted for by the Wernerian system. . It is two theories, it inay be necessary to say a few stated, that many rocks are found which contain words with regard to their merits, the consistency fragments of others, or which are connected with of their parts, and their agreement with the phe- collections of gravel loose or consolidated. Such nomena which they profess to explain.
fragments and gravel necessarily suppose the ex. The Huttonian geologist commences with the istence of former strau, froin the waste of which
they had originated. It is also observed, that, in these, connected principally with the primary, many of the most extensive strata of the earth, but in general less elevated, and sometimes, remains or impressions of organic substances are though rarely, containing vestiges of sea animals, found, both animal and vegetable, and of course is it not reasonable to believe that these hare these must have existed prior to the formation of been intermediate in their formation, and that at such strata.
least the few species of those animals, whose re“These facts are considered by the Huttonian mains are found in them, had begun to exist at geologist as sufficient proof of the existence of a the time they were formed.' babitable world, from the decay of which ours The Huttonian theory gives a solution of these has been formed. They are, however, equally phenomena, according to its own peculiar prinwell accounted for by the Neptunist, without ciples, which is pressed with greater difficulties admitting such a supposition. It is supposed that than any which its adherents have been able to the existence of marine animals commenced after raise against its rival system. As all strata, acthe crystallisation of the great primary strata; cording to it, are arrangements from the wrecks and that after that period, too, the waters of the of a former world, they ought all to have their ocean began to diminish in height, so as to leave proportion of animal remains and fragmented elevated land, on which vegetation commenced. fossils assigned them. No reason can be given The retreat of the ocean continued to be gradual for their existence in one situation which would for many ages, and during this time the second- not lead us likewise to expect their occurrence ary strata were formed. It is obvious, there in another. Gneiss, mica-slate, and clay-slate fore, that the fragments of rock, the sand and are stratified rocks, and should have these proofs gravel which these often contain, or with which of their prior history inscribed upon them as they are associated, or which even in many cases legibly as slate-clay, sandstone, and the calcarecompose the greatest part of their mass, might ous fossils. In the former class, however, they originate from the disintegration of the primary are seldom or never found ; in the latter they are strata above the level of the sea ; a disintegration met with in abundance. The Huttonians endeato which, in this early period of their consolida- vour to remove this inconsistency, by answering, tion, they might even be more liable than they that the gneiss and mica-slate are in a higher deare now. And the origin of the remains of marine gree of crystallisation than the other kinds of animals, and even of vegetables, found in the se- rock in which petrifactions occur, and that, in the condary rocks, it is obvious, are equally well ac- fusion which enabled them to assume that state, counted for on this theory, since the existence the traces of animal exuviæ may have been of these may have begun previous to the existence destroyed. This statement would obviate the obof these strata. The facts, therefore, do not jection, if it accorded with the fact; but unforprove the hypothesis of Dr. Hutton, since, on a tunately, it has not that recommendation. We different hypothesis, they are explained with need only refer to that species of marble in which equal facility.
organic remains occur in abundance, to show It has been affirmed, however, that the same that a higher perfection of the crystalline strucappearances of sand and gravel, and of marine ture than is by this hypothesis consistent with impressions, are occasionally to be met with in their appearance in gneiss, actually admits of the primitive strata, and that of course the Wer- their existence in the carbonate of lime. Withnerian explanation is defective; for marine ani- out allowing, with the Wernerian, a priority in mals are not supposed to have existed at their the arrangement of these different kinds of rocks formation; and it is obvious that the presence of how shall we account for such pheno ena? and sand and gravel are true indications of strata hav- by allowing such successive formations, how ing existed before them.
easily are they explained ! Nor does the Hutto*But it is asserted, on the other hand, by Nep- nian theory labor with greater success, to recontunian geologists, that such appearances are not cile the occurrence of fragments in some peculiar to be met with in strata truly primitive; but that situations with its general principle of stratificawhen they do occur in strata, not of the secon tion. There frequently occurs between the strata, dary class, it is in those of the intermediate kind, or what Werner calls the primitive and flætz formaor what Werner terms the rocks of transition. tions, a bed of conglomerated fragments of rolled These, it will be recollected, are supposed to be pieces. This appearance, for instance, occurs posterior in their formation to the primary, but placed upon a basis of clay-slate, and covered prior to their secondary strata, and to have been with a stratum of sandstone, and is easily acformed at that period when the existence of ma- counted for on the Wernerian doctrine of the rine animals, or at least of some species of them, prior existence of granite, from the rocks of which had commenced; and of course they may occa- such debris might be detached as formed these sionally be found with impressions or remains of beds, while the waters of the chaos still covered these beings. This supposition is liable to no the gneiss and the somewhat lower levels of the difficulties, and seems to follow justly from the globe. Let us hear the Huttonian explanation of facts. Since certain rocks, having peculiar cha- this fact, as detailed by Mr. Murray. racters, and composing the most elevated parts “The explanation, according to the Huttonian of the globe, are found destitute of organic re- hypothesis, involves a supposition so extraordimains, while in others they are in abundance, nary as to furnish a singular contrast with that doth not this afford a presumption, that the for- of the Neptunian. It is supposed that the schistus mer had been produced prior to the period when had been formed in beds nearly horizontal, and these beings began to exist ? and if rocks are that, by an expansive power exerted from beneath, found intermedia'e in their character between these had been elevated to the surface, and
placed in a vertical position. In this situation, haustible? and will there always be sufficient the bed of gravel, from which the breccia is quantities of them available for the purposes of formed, had been deposited on the summit of the making worlds when the old are worn out? or, vertical schistus. To admit of the formation of in other words, for answering the ends of the the horizontal strata of sandstone, it is further theory in the renovation of nature? We all supposed, that the schistus, with this superincum- know that a substance which has undergone bent breccia, had again sunk in the ocean, and combustion, forms products which are not caparemained depressed for ages, till the materials ble of undergoing a second time the same of the sandstone were deposited on it. These process. materials are supposed to have been then conso- It should be observed, however, that the lidated by the central fire operating on them, ablest adherents of the Huttonian hypothesis even with the intervention of the deep strata of have entirely renounced the use of fuel in the schistus on which they are incumbent; and, production of the central heat, and have resorted lastly, we are told that the whole, when thus to other means of exciting and supporting it. prepared, were again elevated by a new exertion Most of them also have given up the solar rays, of heat. It may surely be affirmed, without far- friction, and condensation : indeed the suppor ther reasoning, that suppositions so extravagant sition on which Mr. Playfair, the ablest supand improbable can never be real interpretations porter of the system, finally rests, seems little of the operations of nature.'
else than the old doctrine of occult qualities. The second class of operations in the order of If his hypothesis has any meaning, it implies, succession, according to the Huttonian theory, is that an immense heat was originally stored in the process of consolidating, deranging, and ele- the lower parts of the earth, and that it is there vating the earth's crust, formed, as above de preserved by the mutual action and reaction of scribed, at the bottom of the sea; and the second the bodies in which it resides upon each other. great principle it assumes is the agency of inter- But its preservation in the same volume and nal heat for accomplishing these purposes. By intensity, without any fresh supply, is contrary employing this agent, and assigning it so import- to all the laws by which the action of heat is ant functions, the Huttonians have exposed their regulated. The only condition on which the system to objections evident to those least ac- hypothesis of its accumulation would be conquainted with geological speculations, and which ceivable, would be a state in the bodies that the most able Huttonian cannot satisfactorily ob- contained it, so completely insulated that they viate. The first thing that strikes us as a difficulty, could diffuse no more of it than what they rein the conception of this theory, is the immense ceived; or, in other words, a state in which no volume and intense force of that heat which could new distribution could take place, because the melt or soften masses so gigantic in their bulk, most perfect equilibrium of temperature was and so infusible in their nature, as those that established among all the bodies which could, compose the habitable world.
by their vicinity, partake of it, either by radiaThis, however, is an objection founded rather tion or through the medium of conducting subupon a comparison of the great operations of stances. Now it will not surely be pretended nature, with the limited scale on which we con- that there is, in the bowels of the earth, any reduct our own, than upon any natural inconsis- gion so insulated. Indeed the simple idea, that tency in the theory against which it was alleged. the central fire has softened the strata which
There are objections to the principle of the were formerly cold mechanical deposits, presupHuttonian theory of a different kind, and not so poses a new distribution of its influence, with a easily answered. What is the nature and source consequent decrease of intensity in its original of this central heat ? and what are the laws by repository; and thus the very purpose for which which it is regulated? These are questions, in its operation is assumed cannot be accomthe answers to which the supporters of the Plu- plished, without destroying the necessary conditonic system are certain to involve themselves in tions of its existence. difficulties, if not in contradictions. Does this The other phenomena exhibited by veins, heat arise from combustion ? No; for combus- beds, and individual fossils, are more hostile to tion requires conditions for its existence which the hypothesis that employs fire in producing are not to be found in the circumstances under them, than even those which we have stated which this central heat is supposed to act. But we cannot at present enter farther into the Where could such a quantity of combustible subject. We need only add that Dr. Boué matter be found, as could fuse and eject those seems to have adopted from the Huttonian theory mighty chains of mountains which extend so far some valuable suggestions, and that the comand rise so high? If combustible substances mendation of M. Necker, with respect to the should be found in the magazines of nature, habits of Saussure as a geologist, seems well worwhence could come that gas which is neces- thy the attention of all students of this science. sary for this operation? The circumstances . In proportion to the avidity with which he of compression under which the central heat is sought for facts, was the care with which he supposed to act, and the consequent exclusion avoided vain speculations. If he sometimes from oxygen or atmospheric air, are sufficient to advances a hypothesis, it is with a reserve justly destroy every idea of combustion.
admired, although rarely imitated, and only But even though we should admit the possi- when the facts seem imperiously to command bility of ordinary burning, in the instance before it. When new facts come in opposition to his us, are the stores, both of the combustible ma- former opinions, he abandons or modifies them terials and the supporters of combustion, inex- without regret.'
GEOMANCER, n. s. Γη 2nd μαντις, και
GEOMANCY, GEOMANTIA, is performed by GE'OMANCY, n. s. prophet. Whatever means of a number of little points, or dots,
Geomar’TIC, adj. relates to the persons made on paper at random: and by forning er acts of fortune-tellers, astrologers, &c. from the various lines and figures which those
What say we of hem that beleven en divinales, as points present, a pretended judgment of futurity, by fight, or by noise of briddes or of bestes, or by sort
upon any question proposed. The word is deof geomancie. Chaucer. The Persones Tale. rived from the Greek and
Havrela, divination; Fortunetellers, jugglers, geomancers, and the incan- it being the ancient custom to cast little pebbles tatory impostors, though commonly men of inferior
on the earth, and thence to form their conjecrank, daily delude the vulgar.
Browne. According to some there are four kinds of divina. tures, instead of the points afterwards made use tion; hydromancy, pyromancy, aeromancy, and the divination performed by means of clefts or
of. Polydore Virgil defines geomancy a kind of mancy.
. Two geomantick figures were displayed
chinks made in the ground; and supposes Above his head, a warrior and a maid;
the Persian Magi to have been the inventors of One when direct, and one when retrograde. Dryden. it.
G E O M E T R Y.
GEOM'ETRY, n. 6. Fr. geometrie ; yes
How easily does an expert geometrician, with one GEUM'ETER, N. S. ωμετρία και γεα
glance of his eye, take in a complicated diagram, made GEOM'ETRAL, adj. Tpéw, to measure. Per- up of many lines and circles !
Id. GEOMETRICAL, adj. taining to the art of
DEFINITIONS OF THE SCIENCE. GEOMETRIC, adj.
measuring the earth : GEOM'ETRIZE, v. n. the science of quan
GEOMETRY, Gr. yew perpua, Fr. geometrie, oriGEOMETRICALLY, adv. tity, extension, or ginally signified the art of measuring the earth, GEOMETRICIAN, n. s.
magnitude, without or any distances or dimensions on or within it regard to matter.
but it is now used for the science of quantity, ex
tension, or magnitude, abstractedly considered, A geometrical scheme is let in by the eyes out the without any regard to matter. Geometry is demonstration is discerned by reason. More.
usually divided into speculative and practical ; Wkat a world of books offers itself, in all subjects, the former of which contemplates and treats of arts, and sciences, to the sweet content and capacity the properties of continued quantity abstractedof the reader! In arithmetick, geometry, perspective, ly; and the latter applies these speculations and opticks, astronomy, architecture, sculptura, picturá, of theorems to use and practice. which so many and such elaborate treatises are of late written.
Burton. Anat, Mel.
The word geometry literally signifies measurHe that shall but see that geometrical tower of Gasuring the land that first gave occasion to study
ing of the earth, as it was the necessity of meareganda at Bologna in Italy, the steeple and the clock the principles and rules of this science, which engine of Archimedes to remove the earth itself, if he has since been extended to numberless other had but a place to fasten his instrument. Id. speculations. Some define it the science of en
'Tis possible geometrically to contrive such an arti- quiring, inventing, and demonstrating all the afficial motion as shall be of greater swiftness than the fections of magnitude. Proclus styles it the revolutions of the heavens.
Wilkin's Math. knowledge of magnitudes and figures, with their For he by germetrick scale
limitations; as also of their ratios, affections, Could take the size of pots of ale. Hudibras.
positions, and motions of every kind.
In a word, geometry, together with arithmetic, Although there be a certain truth, geometricians
now forins the chief foundation of all the mathewould not receive satisfaction without demonstration thereof.
matics. Mast men take the measure of God just by the
HISTORY OF GEOMETRY. same geometrical proportions that he did that gathered The invention of geometry is generally ascribed the height and bigness of Hercules by his foot ?
to the Egyptians. Herodotus, Diodorus, Strabo,
and Proclus, all agree that the annual inundaWho thinks all science, as all virtue, vain;
tions of the Nile gave rise to it, by carrying away Who counts geometry and numbers toys,
the land-marks and boundaries of estates and And with his foot the sacred dust destroys.
farms; and covering the surface of the ground Dryden.
with mud, which effaced every trace of their forAll the bones, muscles, and vessels of the body are mer limits. Hence the Egyptians were obliger contrived most geometrically, according to the strictest every year to distinguish and lay out their lands rules of mechanicks.
Ray. by the consideration of their figure and quantity, Does not this wise philosopher assert,
that every person might have his own property : That the vast orb, which casts so fair bis beams, and thus, hy repeated experience and practice, Is such, or not much bigger than he seems? in drawing figures, lines, and schemes, for this That the dimensions of his glorious face
purpose, they gradually formed an art which, Two geometrick feet do scarce surpass? Blackmore.
from its origin, in measuring of lands, the Greeks He became one of the chief
ers of his age.
at last named ywuerpia, geometry. By farther
Watts. contemplation on the draughts of figures, their VOL. X.