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to the molten ocean seething within the of the elements of earth which Professor globe, and forcing its way out from time to Cotta, in his Lithology, speaks of as “ a per. time.” When the crust of the earth was petual circulation of matter in the world too thin to oppose much resistance to the of rocks." outbreak of these internal fires, they so On this head we will quote a passage constantly forced themselves through, that from Professor Cotta's book. The second some of the earlier rock deposit is perforat- edition of that thoroughly clear, full, and ed with numerous chimneys, narrow tunnels systematic treatise upon Rocks has, this as it were, bored by the liquid masses that year, been translated by Mr. P. H. Law. poured out through them.
rence into an English edition that includes But even that thin crust, how could it be the author's new material, and other inforformed ? Astronomy, says Professor Agas- mation which the translator himself has siz, shows our planet thrown off from the added with the author's sanction. This is a central mass of which it once formed a part, part of Professor Cotta's summing up of his to move through spaces cold enough to chill subject : its surface. The first effect of cooling was contraction of its surface into a solid film It we take a general review of the various or crust. That crust would shrink, as the formations and transformations of rock, we cooling continued, wrinkles and folds would shall discover in them a perpetual process of arise in it. Here and there, where the ten- circulation or rotation of substances, and of
their different states. sion was too great, there would be cracks. but the forms in which they appear and the
The substances remaio, Meanwhile, the crust would thicken gradu- mode of their combinations vary. ally as the mass within became affected by Disregarding for the moment the first solid the outside temperature.
products of cooling on the earth's surface, as The cooling that solidified some of the not being capable of indentification at the presconstituents of earth, caused also the rising ent day, we may most conveniently enter the of vapours, their condensation into clouds, circle of transmutations with the eruptive ignethe falling of rains, the gathering of waters ous rocks, as approaching most nearly to origiupon the face of the earth. As soon as the nal formations. These, then. are constantly
attacked and decomposed by chemical and me wash of an ocean wore the surface the
chanical forces acting from their surface inwards, solid crust, it swept material from it to be and from their cracks and fissures outwards. deposited as sand, or mud, or pebbles at its
The products of this decay are deposited bottom, layer upon layer. So the crystal- either in the form of chemical precipitates or line fire-born rocks were covered in many mechanical aggregates. By chemical process places with layer upon layer of the deposit of precipitation cavities and fissures in rocks befrom the waters which had reduced some come filled up (amygdaloids and veins), deposits part of them to a fine dust. So came the are made at the mouths of springs of limestonegreat division between unstratified and tuff, siliceous-tuff, bog-ore, &c.; or else other stratified, igneous and aqueous rocks. Be- crystalline rocks are formed, such as gypsum or tween them in character are the stratified hand (partly aided by organic processes), there
. By mechanical agency, on the other rocks that have been metamorphosed, more arise the much more important and extensive or less recrystallized by heat. Where the deposits of clay, sand, pebbles, marl, limestone, and molten mass from within has, through crack dolomtie; and during the process of deposit
, in the surface or otherwise, come into con- carbon (in the form of carbonic acid from the attact with, and partially melted, rocks de- mosphere), water, chlorine, and some other subposited by water, clay has been baked into stances, are added to the previously existing
materials. slate, limestone fused into crystalline marble. The geology of Professor Agassiz is
But, like the eruptive masses, all these dedecidedly too much of the convulsive school, posed and washed away by external forces;
posited masses in their turn are partly decom. when he says that “all mountains and and in other parts they become greatly changed mountain chains have been upheaved by internally by pressure and the action of heat. great convulsions of the globe, which rent By means of heat and pressure acting during long asunder the surface of the earth, destroyed periods, parts which thus in the first instance the animals and plants living upon it at the were only mechanically bound together, enter intime, and were then succeeded by long in- to new chemical combinations with each other, tervals of repose.” As to the first part of and assume a crystalline state more or less the story of the globe, in fact, we prefer the analogous to that of the crystalline mineral teachings of Sir Charles Lyell to those of able in many cases that the substance of these
aggregates of the eruptive rocks. It is even probProfessor Agassiz. Cosmical operations, derivative rocks has been fused and become mighty in their results, have for the most eruptive a second time. part been gradual as those rearrangements Thus the process of destruction and new
formation of rocks, be it ever so slow, and / and “ the Silurian Beach” is, therefore, the therefore difficult of observation, has never, at subject of his second chapter. Around the any time of the earth’s history, been interrupted, city of Cincinnati, Silurian shells and crusbut continues at the present day; and not only tacea may be collected by cartloads. A is this true of the original formations, but the
naturalist, new products of consolidation, of deposits, and find it difficult to gather along any modern
says Professor Agassiz, would of transmutation, have always been equally subjected, and are still subject, to the same seashore, even on tropical coasts, so rich a processes.
harvest in the same time, as he will bring This is the perpetual circulation of matter in home from an hour's ramble outside that the world of rocks.
city. His next chapter is upon
" the In the course of such various and renewed Fern Forests of the Carboniferous Period.” working up and transformation of the same The land of North America at the beginsubstances, with the addition of those others ning of this period included Newfoundland furnished by the air and water, it cannot be and Nova Scotia, the greater part of New matter of wonder that the variety of their groups has been always somewhat on the in England, the whole of New York, a narrow crease; for, if certain processes in this rotation strip along the north of Obio, a great part are altogether universal in their character, re- of Indiana and Illinois, and nearly the whole curring in the same way, everywhere and in of Michigan and Wisconsin. Within this every age, yet in consequence of the general region lie nearly all the Great Lakes. Bemultiplication of conditions and circumstances, tween the elevations of the land were other and the increasing aggregate of their results, inland seas changed by the rains to freshspecial combinations of the same processes water lakes, filled in the course of centuries have constantly arisen in later times and brought with débris from their shores, and transabout special formations of rocks which were formed at last to spreading marshes on which not previously in existence, or which do not belong to the normal phenomena of nature.
arose the gigantic fero vegetation of which This increase in variety of the products of the first forests chiefly consisted. What later times is not confined to geological and ferneries were they, to compare with the mineral substances; a greater and more rapid pretty collections that our ladies now colincrease has taken place in the organic world, lect in hothouse or Ward's case! One goes where the forms of life have multiplied in an back to this primeval time with satisfaction ever ascending ratio (partly in consequence of | for assurance that these new favourites of the change and increase of the conditions of ex- fashion really are one of the oldest families istence from geological causes).
in the world; and then one comes back to The processes of change, to which the outward conformation of the globe's surface is 1866 with a welcome for a fern book by subject, likewise multiply more rapidly than Mr. John Smith, who has been studying mere strictly geological phenomena.
ferns at Kew since the year 1822, and has Reasoning, therefore, from the past and from been at the making of the whole Kew colanalogy with other kingdoms, we must expect lection. the species of rocks and kinds of rock-formation Mr. Smith's book is a systematic enuto go on increasing indefinitely for the future, meration and description of the cultivated as they have been increasing continually ever ferns, with a history of the introduction of since the first solidification of our earth’s crust. exotic ferns, instructions as to cultivation
and the etymology of their ungainly names. The earliest American land, says Mr. Such a book will be welcomed now by hunAgassiz, was a long narrow island, almost dreds of amateur collectörs, although fitty continental in its proportions, since it years ago it would have had as much chance stretched from the borders of Canada nearly of a general sale as if it had been published to the point where now the base of the in the carboniferous age for the use of the Rocky Mountains meets the plain of the Cephalopods. Says Mr. Smith, Mississippi Valley. We may still walk along its ridge and know that we tread
Though Ferns now occupy a conspicuous upon the ancient granite that first divided place in our gardens, and are in high favour the waters into a northern and southern with cultivators, it is only in comparatively ocean."
recent times that they have been brought
into notice. During the last century certain Then came the age called Silurian be- classes of plants came into fashion, and after a cause Sir Roderick Murchison happened to Thus: Tulips were once the rage. At the
season of popularity again fell into disrepute. study its remains in water upon land once time of the est ablishing of the several provincial ascribed to the Silures. In the Silurian Botanic Gardens, all of which were founded age, says our author, the world, so far as it upon a strictly botanical footing, though many was raised above the ocean, was a beach, l of them havo now, to a greater or less extent, degenerated into places of amusement, the plants while to the south-east of it lay the central plain greatest demand were those of our New Hol-teau of France. Great Britain was not forgot land and Cape colonies, principally the Heaths, ten in this early world : for a part of ibe Proteis, Aloes, and their kindred. 'In after- Scotch hills, some of the Welsh mountains, and years, dealers obtained large prices for Cac- a small elevation here and there in Ireland, al. tases; but, with the exception of a few of the ready formed a little archipelago in that region. easily-grown and most showy kinds, these are By a most careful analysis of i he structure of the now scarcely saleable. Still 'more recently the rocks in these ancient patches of land, tracing all magnificent-flowering Orchids were promoted the dislocations of strata, all the indications of 10 the first place in our gardens; and though any disturbance of the earth-crust whatsoever, these may still be said to maintain their posi- Elie de Beaumont has detected and classified four tion, the expense attending their cultivation is systems of upheavals, previous to the Silurian 80 great that they are for the most part confined epoch, to which he refers these islands in the to the gardens of the wealthy. Ferns, on Azoic sea. He has named them the system of the contrary, may, as a general rule, be grown La Vendée, of Finistère, of Longmynd, and of in a comparatively inexpensive manner. The Mobihan. These names hare, for the present discovery made by Mr. N. B. Ward, that these only a local significance, - being derived, like plants can be grown to great perfection in small so many of the geological names, from the ornamental closed cases (now well known as places where the investigations of the phenom“Wardian Casts”), suitable not only for the ena wore first undertaken; but in course of drawing-rooms of the wealthy but for humbler time they will, no doubt, apply to all the con dwellinys, renders it possible for amateurs to temporaneous upheavals, wberever they may indulge their love of Ferns without going to the be traced, just as we now have Silurian, Devoexpense of erecting hothouses and employing a nian, Permian, and Jurassic deposits in Ameristaff of gardeners; and it is to be hoped that ca as well as in Europe. this will be the means of retaining them in fa- The Silurian and Devonian epochs seem to vour and spreading them still wider.
have been instrumental rather in enlarging the The enumeration shows that at the present tracts of land already raised than in adding time above nine hundred exotic species of ferns new ones; yet to these two epochs is traced the are cultivated in the various public and private upheaval of a large and important island to gardens in this country; and of these by far the the north-east of France. We may call it the greater number have been introduced during Belgian island, since it covered the ground of the last quarter of a century.
modern Belgium ; but it also extended consid
erably beyond these limits, and included much From the old Fern Forests Professor Agas- of the Northern Rhine region. A portion only siz passes to the Mountains and their Ori- of this tract, to which belongs the central mass gin. Then come to the Growth of of the Vosges and the Black Forest, was lifted Continents. Here is the account given of larged considerably Wales and Scotland, the
daring the Silorian epoch, — which also enyoung Europe in the days when it was Bohemian island, the island of Bretagne, and growing up :
Scandinavia. During this epoch the sheet of
water between Norway and Sweden became In the European ocean of the Azoic epoch dry land, a considerable tract was added to their we find five islands of considerable size. The northern extremity on the Arctic shore; while largest of these is at the North. Seondinavia a broad band of Silurian deposits, lying now bad even then almost her present outlines; for between Finland and Russia, enlarged that Norway, Sweden, Finland, and Lapland, all of region. which are chiefly granitic in character, were The Silorian epoch has been referred by Elie among the first lands to be raised. Between de Beaumont to the system of upheaval called Sweden and Norway there is, however, still a by him the system of Westmoreland and Hundlarge tract of land under water, forming an ex. srück, again merely in reference to the spots tensive lake or a large inland sea in the heart of at which these upheavals were first studied, the the country. If the reader will take the trouble centres, as it were, from which the investigations to look on any geological map of Europe, he spread. But in their grological significance will seu an extensive patch of Silurian rock in they indicate all the oscillations and disturbthe centre of Sweden and Norway. This repre- ances of the soil throughout the region over sents that sheet of water gradually to be filled which the Silurian deposits have been traced in by the accumulation of Silurian deposits and Europe. The Devonian epoch added greatly afterwards raised by a later disturbance. There to the outlines of the Belgian island. To it is another mass of land far to the south-east of belongs the region of the Ardennes, lying bethis Scandinavian island, which we inay des tween France and Belgium, the Eifelgebirge, ignate as the Bohemian islaud, for it lies in the and a new disturbance of the Vosges, by which region now calted Bohemia, though it includes, that region was also extended. The island of also, a part of Saxony and Moravia. The Bretagne was greatly increased by the Devoninorth-west corner of France, that promontory an deposits, and Bohemia gained in dimensions, which we now called Bretagne, with a part of while the central plateau of France remained Normandy adjoining it, formed another island ; much the same as before. The changes of the
Devonian epoch are traced by Elie de Beau- , posed by bigotry upon youthful genius. The mont to a system of upheavals called the Ballons real inference probably is, that the immo of the Vosges and of Normandy, – so called rality of a book is scarcely a matter for for. from the rounded balloon-like domes character- mal argument; it must be decided by the istic of the mountains of the time. To the Car- instinctive judgment of healthy minds. To boniferous opoch belong the mountain-systems of Forey (to the west of Lyons), of the North count up the breaches of conventional mo. of England, and of the Netherlands. These rality is a futile proceeding; for, as in the three systems of upheaval have also been traced case of shooting negroes, everything deby Ele de Beaumont; and in the depressions pends upon the spirit in which the laws are formed between their elevations we find the disregarded. No sort of test has hitherto coal-basins of Central France, of England, and been devised for detecting the presence or of Germany. During all these opochs, in Eu- absence of so refined an essence as a virtuthe surface was attended by a change in the contact with a work produces upon sound rope as in America, every such dislocation of ous spirit, except the immediate effect which animal creation.
There are certain books of popular science are on the Geological plunge into running waters and regard him
The other chapters of this pleasant book which, as Mr. Carlyle says of a performance Middle Age; the Tertiary Age and its self for the rest of the day as more than Characteristic Animals; the Formation of Glaciers, their Progression, and their Ex- them is like arguing about a bad smell. If
ceremonially unclean. · But to argue about ternal Appearance; the glacieis being discussed here generally with regard to their sweet to him, no power on earth can prove
an alderman swears that the Thames smells geological significance. But å special vol
to him that it stinks. ume is to follow, in which Professor Agassiz will add to the excellent studies by Forbes, such matters would really amount to a com
Hence, a great deal of controversy upon Tyndall, and others, of the glaciers of the parison of the moral idiosyncrasies of the old world, his own tracings of the glacial contending critics. In the absence of any phenomena of America. For the glaciers of Europe, he says, the cannot say winther the senses of one are
means of deciding this delicate point, we broken character of the country, intersected morbidly sensitive, or those of the other morin every direction by mountain chains, pre- bidly dull, to immoral images. The legitisents numerous centres of dispersion. Ow
mate form into which criticism runs is, ing to the extensive land-surfaces on the
* You must be immoral because I say so;” American continent, the same set of facts and the only reply is what vulgar boys expresents there a new aspect, enabling some
“ You're another." From this it new light to be thrown on the whole subject follows that most of the ordinary arguments of glacial action.
are beside the point. For example, the question whether a poem is or is not dramatic seems to be generally quite immaterial. It would, indeed, have some importance if we
were discussing the character of the poet, From the Saturday Review.
as distinguished from that of his work. It would be important to prove, if any.one could have any doubts upon the subject,
that Shakspeare was not responsible for SOME recent discussions seem to indi. Iago's sentiments, and that Milton was not, cate that the public mind is in a state of beyond a certain point, to be identified with utter confusion as to the canons by which the devil. In criticising Byron or Shelley it the morality of a literary work is to be de- would be more difficult and more interesting cided. No satisfactory dogmas can be laid to inquire how far their poenis expressed down. Those who are most inclined to a their own convictions; but it would be inmistaken prudery feel the absurdity of draw- teresting only as affecting our judgment of ing a line which would exclude Othello or Byron or Shelley, not as deciding the moCymbeline. Their adversaries cannot quite rality of Don Juan or Queen Mab. If a poet venture to argue that, as the accusation of claims that he does not mean what he says, immorality has constantly been brought the claim may always be conceded; but it against the noblest writings, therefore every really makes no more difference than the one accused of immorality is a noble writer, assertion of Hume that he is not really aror that he has done anything instrinsically guing against Christianity when he tries to virtuous in breaking down the barriers im- 1 prove the incredibility of miracles. The ar
guments will produce the same effect, what- I make it impossible to lay down dogmatically ever may have been the intention of the rea- that a book is or is not immoral, for the soner; and the impure images suggested by effect of a book upon different persons will of the poem will be just as foul, though he may course be infinitely various. There doubthave only been talking in the character of less are persons who are injuriously affected some one else. If, again, he puts forward by pictures or poems in which purer minds false views of philosophy or morality we do can see no harm ; and we must admit that, not condemn him, except in so far as he if the world at large were constituted in the makes those views attractive. An historian same way, conventional laws of decency who proves that tyranny is desirable, or a would have to be more stringent. And philosopher who argues in favour of atheism, this suggests that, even as it is, there is some is generally considered to be immoral ; but use in these much decried laws. We may a poet is going out of his natural part if be easily admit that the English code is at attempts to prove anything: His primary present too strict; and that it is really preobject is merely to draw a picture; and the judicial to morality when the fitness of a truth of a picture, in spite of common criti- book to be read to boys and girls is made cal language, is in strictness an inaccurate the only test of its morality. But for all expression. We may ask whether it is like that, the conventional rules as to literary proor unlike to the object represented; but to priety discharge a very useful function, as introduce the moral qualities of truth or do similar more or less arbitrary rules in falsehood is generally an unfair device for regard to dress and conversation. To the introducing irrelevant prejudices. There is pure all things are pure; there are few or no crime in making a picture or a poem or no topics which may not be handled so as a novel which is like nothing in heaven or to produce a good moral effect. But then, earth or the waters under the earth, though, unfortunately, a large part of mankind is as a rule, it is a rather idle amusement. anything but pure; they have a morbid The ultimate object of any work of art is, capacity for assimilating filth of all kinds, not to make known trụth, but to give plea- and rejecting the healthy part of their mensure ; and the test of its morality is, not the tal food. It is therefore necessary to have quantity of truth which it conveys, but the certain sanitary regulations in society calcuelevating or debasing tendencies of the lated on the assumption that there are many pleasure. Wordsworth is a highly moral persons highly susceptible of moral contagion. poet, because the emotions which he stimu- The sphere allowed to art is somewhat limitlates are always pure and intellectual; the ed; but this is a sacrifice which is necessary truth of his statements is only to the purpose in the present imperfect condition of the in so far as it increases and purifies the world. 'We give up a few beautiful pictures pleasure; otherwise they would be of no and forms, that we may give no occasion for more poetical value than the assertion that a great many more which would have a bad two and two make four, or that it is a sin to moral effect. If the public taste were suffisteal a pin. If, on the other hand, there ciently enlightened to discriminate in all are poets whose stock of images are all cases the healthy from the unhealtby bandrawn from earthly and sensual sources, dling of dangerous topics, no such rules and who constantly appeal to the lower ap- would be necessary. The danger of raising petites in preference to the intellectual part the standard too high is of course obvious, of our nature, a study of them will probably and so is the impossibility of fixing definitely be demoralizing whether they make, or do what it ought to be; for in all cases it must not make, the childish excuse of having depend upon the propensity of people to been only“ pretending.” Unless, that is, abuse the liberty permitted to them. Our the sensual desires are touched in such a English rule, for example, in regard to novels way as to make them repulsive, the orna- is probably overstrained; we might sately ments in which the poet's imagination has allow a somewhat greater latitude; but, on dressed them up will make them more at- the other hand, it seems hard to deny that tractive to those whom he is able to affect; the French have not erred on the other side. and this has simply no reference to the They have some excellent works of art question whether or not the expression is which would have been at once sentenced “dramatic.” It may be that immoral poetry to destruction in England; but, on the other is generally the production of a prurient hand, they have a whole mass of literature mind, but the mental condition of the poet, which represents the entire adult population and the effect he produces on his readers, to be thinking about nothing but how to are distinct questions.
commit, or not to commit, or to hinder or enThis, it is true, raises considerations which courage other people in committing, adultery.