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sano, Genoa, and
Montrouge, upper part.
in the supe
11. Firse TERTIARY LIMESTONE, OR TERTIARY COARSE
Best marked shelly lir estone. Pseudo-volcanic Rocks,-Porcellanite,
Earthy Slag, Tripoli.
SWISS AND AUSTRIAN, MO- ITALIAN AND
FRANCE GERMANY, AND RHINE BASIN. BAVARIAN RAV., HUNGAR. SICILIAN
BASIN. & TRANSYLV.B. BASINS.
shelly. deaux. St. Paul Cassel. fresh and
short beds, Brelimestone, shelly
gonza; veins and
sandy, with trois cha- Sandy limestone, salt water Lichten selenite.
rocks, coulées, Vicen-
steig, and in the upper SubappenLeognan, Common Coarse limestone.
Coarse limestone Fluviatile perhaps
conglo- veins, Vicen-
pecially in centin, Ve-
Sclavonia, Limestone with
&c. with shells, water shells
Not present in
Dusodite of Si-
Sometimes Bones of great terrestrial N.B. Uppermost limit of Sulphate
Mammalia or extinct species.
of Barytes and Strontian. LONDON AND Nice, PERPIGNAN, S. W. S. E. OF FRANCE
AUSTRIAN, MORAVIAN, PUY EN VELAY AND
in coulées, Can-
in beds, Auverg-
Marls, with fresh marine and fresh Marls. Menilite, &c. always without shells. Marls.
water shells, water shells, Me-Gypsum, Gypsum. with fresh water shells Gypsum,
lanopside; Vienna; calcareous with
and bones, Agen.
du Garde. tiary sandstone. Siliceous limestone.
K Basaltic beds and
PARISIAN BASIN. LONDON
AND I. Nice, PERPIGNAN, S. E. OF FRANCE, DANISH, N. GER. SWISS AND BA AUSTR. MORAV. ITALIAN AND SIWIGHT BASIN. S. W. FRANCE B.
MANY & Russ. B. VARIAN PASIN. HUNG, TRA. BAs. CILIAN BASIN.
with shells, Tus-
Rhone, nodules. Nagelflub.
with shells, Pest,
zeck Valley in
V. Last Fresh-water Deposit. Local Fresh-water deposits, formed by springs or basins of fresh-water at very different periods of time.
VARIAN BASIN. HUNG. & TRANS. BAS. SICILIAN BASIN.
Isle of Marls, Montpe- Marls, Heiden Marly limestone, Ofen. Limestone, in many
Limestone, Meidlerig, places.
Limestone, Waller Wimpassing in Aus-
N. B. Tertiary rocks exist in the steppes of Asia, in India, in Africa, in the Canaries, Island of Madeiria, and the West Indian Islands (Guadaloupe,
Barbadoes, &c.), in Columbia, and in the Atlantic United States.
CLASS VO-ALLUVIAL ROCKS.
OLD ALLUVIAL FORMATION
EXTINCT AND BURNING VOLCANOES.
basaltic lakes, or the greater height of existing rivers.
and living animals, but no bones of the human race.
Lavas, 1 vitreous,
feldspathic, Marls, AiMarls, Kai- Marls, with
ony ferstuhl, bones and
Meionite, wollastonite, mellilite, &c.
basaltic tufa, short
pumice tufa, sand and marl, with shells and bones of cetacea, in Scotland, &c.
The various substances produced by sublimation
in the volcanoes burning at the open air, and
in those burning under water. (The effects of
both kinds of volcanoes must not be quite
douce of Prevost), of the natron lakes of Hungary and Transylvania, &c., calcareous tuff with rhinoceros bones,
The various substances produced by the solfa-
taras on the continent (Buodeshegy in Tran-
IV. After taking a view of the structure and How far this class of philosophers have ad. arrangement of the crust of the earth, it is almost hered to well ascertained principles, in their impossible to avoid forming some theory to ex- geological investigations and reasoning, is a difplain the mode by which it was brought to its ferent question. All that we mean to claim for present habitable condition. Almost every ap- them is, that there is no natural presumption pearance it presents informs us that it has under against a theory; that their object is legitimate gone mighty revolutions: the regularly formed when they endeavour to form one; and that there horizontal strata of some formations are similar are not wanting appearances which may render to the arrangements of those mechanical deposits one plausible. Of late years two principal from water which at present come under our theories have been proposed to account for geoobservation; and the crystalline structure of logical phenomena, which have attracted such others forces us to infer à liquidity, by which interest as to cause a complete oblivion of every only, according to the present laws of nature, previous hypothesis. Though diametrically opthat structure could be produced. The globular posite in many of their principles, each has men form of the earth is a sufficient proof that it was of science and ability for its supporters, and each once liquid, because the liquid condition only explains a certain class of facts to the satisfaction could have allowed it to assume such a shape. of its friends. The one which ranges the greatest
The occurrence of petrified sea-shells, and of the number of mineralogists and chemists among its petrified remains of fishes on high mountains, is adherents, is called, as we have already stated, also a certain evidence that the waters must at the Neptunian or Wernerian, from Werner the one time have risen beyond their present level, great mineralogist of Freyberg, who gave it and that these eminences were of posterior for- first the form of a theory founded on observation. mation to the animals whose exuviæ they enclose. The other is denominated the Plutonic system, When petrified bones and horns of land animals from its employing the agency of subterranean are found in fossils, the same inference may legi- fire, in accounting for actual appearances, or timately be made. The immense quantities of Huttonian, from the name of the late Dr. Hutmineral coal found in the bowels of the earth, ton, who gave that particular modification of it and the connexion that may be traced between which is now considered the most consistent and it and moss, or the remains of plants decaying philosophical; and which Mr. Playfair and under our observation, carry us back to a lux- Sir James Hall have so ably advocated and illusuriant vegetation before the period when our trated. Both these systems, it will easily be present soil was formed, or perhaps before the perceived, agree in assuming a state of Auidity crust was arranged that supports it.
as necessary to explain the texture of particular It is needless to multiply examples where ge- fossils, and the general structure of the mineral neral appearances are so striking, or to en- kingdom; but they start in direct opposition with gage in abstruse reasoning where inferences are regard to its cause, and of course give a different so easily drawn. Indeed, without any induc- account of every subsequent event, the Wernetion of facts, but what a very superficial expe- rian attributing that fluidity to solution in water, rience affords, every one almost is compelled, the Huttonian to igneous fusion. The products from existing phenomena, to form some hypo- of a mass held fluid, by one of those agents, is thesis; and that hypothesis will be more or less in many cases so different from those which rational, according as it is suggested by a greater would be formed by the other, that the geologist or smaller number of observations, and explains need not despair of being ultimately able to disconsistently a greater or smaller number of facts. criminate between them, and to determine what There can be no presumption in tracing the laws kind of agency has principally been employed. of Nature through her most magnificent opera- In the mean time we shall state the opinion tions, any more than through her most minute, entertained of the manner in which each is supprovided we strictly adhere to the course she points posed to have operated, by those who make use out, and do not twist her language to support our of it in their respective systems. own preconceived notions. The power of gra The Wernerian supposes that the surface of vitation, by which a stone is brought to the earth, our globe presented at first a chaotic mass, in retains the planets in their orbits; and the prin- which the materials that compose its solid strata ciple of electricity which, when excited in a piece were held in solution by water. In that mixed of glass or of wax, only enables it to attract a and confused state, certain changes in the rela pith-ball or the fibres of a feather, produces, tive situation of the principles took place by when collected in the sky, all the terrifying effects motions among them, and the particles were thus of a thunder-storm. There surely can be no placed in a condition favorable for the exergood reason why we should not investigate the tion of chemical affinities. The operation of circumstances in these two classes of facts, and these chemical attractions was to bring the mawhy, after due investigation, we should not refer terials on which they acted into the crystalline them to the same law, though the scale on which shape, which would be more or less perfect in we trace its operations be so extremely different. proportion to the freedom in which they were In the same manner, no prejudice should exist formed, or the interruptions to which in their against the theories of the geologist, though he formation they were subject. An aggregated should apply those mechanical and chemical mass of crystals was thus formed, consolidated principles, which he can trace in the formation and precipitated in the same manner as at preof a minute crystal or a stalactite, or in the ar sent the crystals of salts are deposited from their rangement of the bottom of a river, to account solution in water. This first precipitation from for the present appearances of the habitable the chaotic fluid constituted the rocks of the priworld.
mitive class, so called from this inferred priority
of formation. In support of the conclusion on that organic remains, no vestige of wnich can be which this name is grounded, the nature and found in rocks of the primitive class, and which position of these rocks are appealed to. They can be but sparingly discovered in the transition are evidently in a highly crystalline condition, series, increase in quantity and variety as we and they are found nearer the centre of the earth, ascend from the old red sandstone, the earliest of than any other strata of the mineral kingdom. the secondary strata. From the nature of the mass before this primitive The earth, however, if now arranged in the subsidence, neither animals nor vegetables could form which it at present assumes, was destined exist; at least there have been found in these to
hty catastrophe. The waters rocks none of their remains. After these preci- which had subsided and left the dry land for the pitates were separated that compose the primi- support of animals and vegetables, from inscrutive class, a nucleus was formed on which sub- table causes, again rose, resumed their former sequent depositions might rest; and the waters; bed, and a seeond time a chaotic fluid invested from a cause which it may be difficult to explain, the crust of the earth. This fluid must have seem to have subsided and left a part of the solid ascended and almost covered the highest mouraggregate nearly dry. There is nothing in this tains, and in the words of Thomson, theory, however, which requires us to pronounce
• A shoreless ocean tumbled round the globe.' upon the question of the time which it might This rise of the waters, Werner finds necessary take for these crystallisations and subsidences to account for the position and structure of the to take place: or bow rapidly or slowly (as we secondary trap formations, so strangely altershould term it) they might be effected by the dating with or, overlying the other secondary Divine Power.
strata. This kind of formation he supposes must Still in the fluid the materials of the other once have surrounded the earth, and formed strata existed, and these, from similar attractions, almost a continuous crust, enclosing within it had their tendencies to precipitation and arrange the other strata ; but, by the sudden recession of ment. Precipitates, accordingly, were formed, the waters, that crust was broken, and, the greatand arranged on the solid mass already existing. est portion of it being carried away, there were These, however, found to differ considerably only left those 6 shreds and patches' of it that from the primitive class, in having a less perfect appear in the shape of detached mountains, crystalline structure, and in containing mixtures columnar eininences, or confused masses of tufa. like mechanical depositions. Prom these cir- To the same period may be referred the origin cumstances they are classified apart under the of the coal formation; and to the same causes name of the transition series, and their formation
are its arrangements to be attributed. It is eviis accounted for by supposing, that, as the chaotic dently and confessedly a substance of vegetable fluid was now diminished in depth, its waves product, and presupposes the existence of a most would descend still lower, and come into more luxuriant vegetation, before the organic kingimmediate contact with that part of the earth's doms were involved in destruction by waters of crust already consolidated, and by their agitation, the ocean. might detach portions of it to mix with the mate After this great catastrophe, the waters again rials still in solution, but gradually depositing; retired from off the face of the earth, and left the and thus might disturb their formation. In ad- dry land for the plants and animals which now dition to this constant wearing action of the cover its surface. As they subsided, the exposed waves, those parts that were gradually elevated parts were acted upon by the influence of the above the subsiding waters would be exposed to ocean and the elements. Fragments were broken other causes of attraction from the elements. off from the solid rock, the softer portions were
The waters continued to subside, and new separated from those more indurated, successive strata began to make their appearance, forming layers of the surface were rendered friable and rocks of the secondary class; but as the action worn away. The debris thus formed was washed of the elements now extended over a greater from the higher to the less elevated ground, from surface, and the force of the chaotic waves in- mountainous country and precipitous eminences, creased, we find greater supplies of mechanical to plains and valleys; and being accumulated on deposits. These rocks, therefore, having been the lower levels, and mixed with decayed animal partly composed of the debris, or disintegrated and vegetable substances, composes the different fragments of the two former classes, have less of species of alluvial rocks, and all the varieties of the crystalline structure, and are arranged more fertile soil. generally in parallel layers, somewhat like suc The only other portion of the crust of the earth cessive mechanical deposits from a fluid. They for which it would be necessary to account, and occupy a lower level than the mountain masses, for which the theory under consideration can from the detrition of which they appear partly afford no explanation on its peculiar principle, to have been formed, and rest upon the more are those formed of the products of volcanic fire. crystallised strata as their basis. They often This class of rocks is so inconsiderable when exhibit striking characters of their origin and compared with the extent of the stratified masses, mode of formation, as may be seen in some kinds and apparently so unconnected with them, that of sandstone, puddingstone, and breccia. any explanation that may be adopted concerning
When the waters had retired so much as to it will not much affect a geological hypothesis, permit the formation of this class of rocks, and calculated to apply to the state of the more had ceased to cover them, the crust of the earth universal formations. The foregoing is the gewas prepared for supporting animal and vegetable neral outline of the Wernerian system, but there life, and received from the hand of nature fami- is an observation or two still necessary to comies of both in abundance. Accordingly, we find plete it.