Wichtig, considerable, Wille, m. will, mind; 3ufluchts'stätte, f. asy- liarity, especially by children. Ex.: Väterchen, dear father important; Mütterchen, dear mother. Schwesterchen, dear sister. &c. lum, refuge. Mit Güte richtet man in den meisten With kindness, one in most Fällen mehr aus, als mit Gewalt. cases, accomplishes than with violence. more The princes of Europe proceed arbitrarily and violently against their subjects. The English sought with all (their) power to obtain the supremacy in America. By such conduct, a breach be. tween the two friends must necessarily arise. He confines himself to no particular hours, but works according to (his) leisure. Die Fürsten Europas verfahren ei'genmächtig und gewalt'sam ge gen ihre Unterthanen. Die Englänter fuchten mit aller Macht die Oberherrschaft in Amerifa zu gewinnen. Durch ein solches Betra'gen muß nothwen'tiger Weise ein Bruch zwischen beiten Freunden entstehen. Er bintet sich an keine besonteren Stunden, sondern arbeitet nach Muße. Aus Versehen kann oft das größte By inadvertence the greatest Unglück entstehen. misfortune may often occur. 1. Die Franzosen eroberten Spanien mit Gewalt der Waffen. 2. Die Schneelawinen in der Schweiz ftürzen oft mit furchtbarer Gewalt in die Thäler. 3. Die Einwohner dieses Landes schleppt man gewaltsam hin weg. 4. Mit aller Macht konnte er nichts ausrichten. 5. Die Griechen vertheidigten sich mit aller Macht gegen die Perser. 6. Der Schwächere muß nothwendiger Weise dem Stärkeren gehorchen. 7. Beinahe ganz Asien gehorchte dem Willen der Römer. 8. Um sein Leben zu fristen, mußte er nothwendiger Weise arbeiten. 9 Themistocles suchte nothgedrungener Weise eine Zufluchtsstätte am persischen Hofe. 10. Mein Freund vertraute mir gestern Abend unter vier Augen ein wichtiges Geheimniß an. Nachdem die Schule aus war, spielten die Kinter nach Luft unter den Bäumen des Gartens. 12. Alle Anwesenden kleideten sich nach der Mode von siebenzehn hundert neun und achtzig. 13. Wegen seiner Amtsgeschäfte hatte er wenig Muße zu Vergnügungen übrig. 14. Schiller konnte sich nun nach Muße in Mannheim literarischen Beschäftigungen widmen. 15. Ich habe aus Versehen einen antern Regenschirm mitgenommen. 16. Ir. rungen entstehen aus Mißverständnissen und Versehen. 17. Glücklicher Weise konnte er sich vermittelst seines Passes legitimiren. 18. Glücklicher Weise hatte ich noch zur rechten Zeit die Gefahr entdeckt. 19. Glücklicher Weise traf ich ihn auf der Straße. 20. Es ist bei dieser großen Feuersbrunst glücklicher Weise kein Menschenleben verunglückt. 21. Scherzweise darf man sich schon Manches erlauben. 22 Er berührte diese Scene scherzweise. 23. Ich liebe vorzugsweise die französische Sprache. 24. Er durfte vorzugweise in das Zimmer des Fürsten gehen. 11. 1. The inhabitants of Holstein defended themselves with all their power against the Danes. 2. William the Conqueror overcame England by force of arms. 3 Those brave soldiers forced their way with tremendous violence through the ranks of the enemy. 4. They forcibly hindered him from his escape. 5. Do you like the German language? 6. Yes, I do, but I especially like the Italian language. 7. At the present time he is especially occupied with the German and Spanish languages. 8. Fortunately I found my friend at home. 8. He is obliged to listen to the orders of his superiors. 10. Most people dress themselves after the French fashion. 11. I took unknowingly the hat of another. 12. My friend fortunately discovered the danger which threatened him. 13. By way of jest he told me many a truth. 14. Secretly you may tell many insults. 15. The princes of Germany proceed arbitrarily in ruling their dominion SECTION LXVIII The syllables chen" and "lein" are suffixed to nouns and form diminutives. These diminutives are always of the neuter gender, and change the radical vowel, when it admits of it: Der Hügel, the hill. Das Hügelchen, the hillock. Die Kugel, the globe or ball. Das Kügelchen, the globule or the little ball. Nearly all nouns may take these suffixes, and many drop or change their final letter. Ex.: Der Knabe, the boy. Das Knab fein, the little boy. Die Stube, the room. Das Stübchen, the little They are used also as terms of endearment or fami room I. In die Höhe in the high, on high, upward, &c., as, Gr sprang in die Höbe; he sprang up. In tie Höhe richten; to raise, to elevate, to direct upward. Ex.: Diese Bücher werden für alte gelten, und ich werde deßhalb keinen II. Gelten is variously translated, "to be worth, to pass for," &c. Eingangszell zu bezahlen haben; these books will pass for old ones, and I shall therefore have no duty to pay. Dieser Mann gilt viel in der Stadt; this man has great influence in the city. gilt dieses Pferd? What is this horse worth? Was gilt's? or Was gilt tie Wette? is equivalent to our, "What will you bet?" "How much is the stake?" &c. Es gilt ein Leben; there is a life at stake, &c. EXERCISE 71. An'erkennung, f. recog- Fabrik', f. fabric, ma- Leiftung, f. perform. nition, acknow- nufactory, factory; ance, accomplishledgment; Fischchen, n. little fish; ment; Antrieb, m. impulse, Gänschen, n. gosling; Leutchen, little people; Gärtchen, n little Nierlich, neat, nice, Betrieb, m. business, garden; pretty; trade; Häuschen, n. cottage; Prophet, m. prophet; Bewundern, to admire, Höhe, ƒ. (See above) Republika’nisch, repub to wonder; I.); lican; motive; | Brauchbar, useful, ser- Hüpfen, to hop, jump, Brüderchen, n. little Hütchen, n. little hat; brother; Käßchen, n. pussy; Der'gestalt, in such a Keinesfalls, in no wise; m. Satur. Samstag, day; Grat, late; Thierchen, a. little animal; Kitchen, n. little chest; Trieb, m. driving, inEin'richten, to arrange, Klatschen, to clap; stinct, inclination. order; Lämmchen, n. lambkin; manner, so; 1. Haben Sie dieses niedliche Gärtchen gesehen? 2. Nein, denn ich be wunderte jenes hübsche Häuschen. 3. Es gehört zwei alten Leutchen, welche ich kenne. 4. Was sind das für niedliche Thierchen? 5. Es fint in tem Garten eine Menge ganz junger Lämmchen. mit seinem Brüderchen. 7. Wollen Sie mir jenes Kistchen geben? 8. 6. Dieses Märchen strelt Wollen Sie dieses auf dem Tischchen haben? 9. Sehen Sie, welch ein hübsches Hütchen! 10. Das Kindchen hat große Freude an seinem Käßchen und an seinem Gänschen. 11. Richten Sie es so ein, daß Sie bis Samstag Morgen in meinem Hause sein können. 12. Machen wir es ders gestalt, daß es für beide Zwecke brauchbar ist. 13. Er soll es so machea, taß er seine Bücher mitnehmen kann. 14. Ich richte es jedenfalls so ein taß ich bis zehn Uhr bei Ihnen bin. 15. Wir machen es so, daß wi feinenfalls zu spät kommen. 16. Sagen Sie Ihrem Bruder, er möchte es dergestalt einrichten, daß es für Jederman zu verstehen ist hoffe Sie werden es so einrichten, daß Sie mit dem letzten Damrsschisse an kommen. 17 36 18. Ein Prophet gilt nirgents weniger, denn in seinem Bater. lande und in seinem Hause. 19. Seine Stimme gilt viel im Rathe. 20. Was gilt's, in zwanzig Jahren ist der größte Theil Europa's republikanisch? 21. Der Trieb zum Bösen ist viel stärker in uns, als der zum Guten. 22 Die Anerkennung unserer Leistungen ist ein mächtiger Antrieb zum Fleiß: 23. Der Betrieb seiner Fabriken wird von Jahr zu Jahr größer. 24. Gr richtete seine Augen in die Höhe. 25. Er sprang vor Freuden in die höhe und Flatschte in die Hände. 25. Die Kinder hüpften in die Höhe. 1. Dear father, will you buy me the little lambkin? 2. No, my dear daughter, but I will buy you the gosling and the little fish. 3. Have you seen that pretty cottage? 4. No, I admired that beautiful little garden. 5. Mary plays with the pussy, and her little brother with the little fish. 6. Look, what a beautiful | re, again; and sentio, I feel. Resentment considered in its origin little chest this is. 7. Men should at all times direct their is simply a return of feeling. Are, then, ill feelings more prevalent thoughts to God. S. Arrange it so, that I may find you to- than good ones, that a return of feeling should be equivalent to morrow at home. 9. I hope you will arrange it so, that you retaliation? That retaliation should involve the bad feeling of may arrive on Monday morning. 10. What is this garden revenge is not surprising, since its root is talio, which calls to mind worth? 11. It is worth more than you believe. 12. What the lex talionis, the law of repaying like for like, “an eye for an were these books worth ten years ago? 13. What will you bet eye, and a tooth for a tooth." (Exod. xxi. 24.) The idea of revenge against this horse? 14. There are five pounds at stake. was moulded into the term long before it became a part of the English language. Yet, while resentment or a return of feeling is used in a bad sense, recompense or repaying is now used exclusively in a good sense. In Scripture, however, these words are used in a strictly judicial and juridical sense, thus: "Vengeance is mine; I will repay, saith the Lord." (Rom. xii. 19.) "To me belongeth vengeance and recompense." (Deut. xxxii. 35.) In these passages, vengeance merely means the penal retribution which follows the infraction, or breaking, of the law. To attribute vengeance to God in the sense of revenge or mere retaliation, is the height of moral absurdity. LESSONS IN ENGLISH.-No. XXXIII. LATIN STEMS. WORDS are undergoing constant change of signification. The changes are in general so slow as scarcely to be noticeable, except at considerable intervals. There is a certain elasticity of mind which contracts and expands, and expands and contracts. Corresponding with these internal movements is a contraction and expansion of the import of words. That term "import" furnishes an illustration. The import of a word is, according to the etymology of the term, that which the word carries in itself. That something, that load or freight, is a variable quantity; it, varies in quality as well as in quantity. The vase swells with its contents, and so its capacity is augmented. The word knave meant once no more than lad, nor does its original knabe, in German, now mean more. Vilain was simply a peasant. A boor was a farmer; a varlet, a serving-man; a churl, a strong fellow. Time-server was used two hundred years ago, quite as often in an honourable sense as in a dishonourable senso Conceits had once nothing concetted in them. LATIN STEMS. Latin Words. genitus, begotten Among the changes which words undergo, two of great importance may be specified; the one is a change from good to bad, the other is a change from bad to good. On the former I add a few things here; the latter must stand over for a little space. Words which originally had a good meaning may degenerate so as to have a bad meaning. Conventiele is a harmless word, signify-gradus, a step ing only a small place of meeting. Our political and religious strifes, however, have thrown around it a feeling of contempt, so that when a Churchman wants to insult a Dissenter he dubs his house of prayer a conventicle:- "It behoveth that the place where God shall be served by the whole church be a publick place, for the avoiding of privy conventicles, which, covered with pretence of religion, may serve unto dangerous practices." -Hooker. The word cunning derivatively denotes knowledge, and the skill which ensues from knowledge. In this sense it was current at the time when our present version of the Scriptures was made; e.g. "If I forget thee, O Jerusalem, Let my right hand forget her cunning."-Ps. exxxvii. 5. Cunning is of the same origin as king, and both denote mental superiority. But, as is exemplified in the slang phrase a knowing one," knowledge ill-directed may issue in craftiness. The word craft, from which the latter is derived, was originally, too, very innocent. Its inoffensiveness is preserved in the term craft as applied to a trade : "A poem is the work of the poet; poesy is his skill or craft of making."-Ben Jonson. Our craft is the Saxon kræft, or the German kraft, which denotes internal strength, such as comes from essential virtues or from knowledge and skill. One or two additional instances of the depravation of words be given. may retro, backwards haeres (haeredis), an heir hered, herit haust hospes (os, itis), a guest,} hospit, host a host iter (itineris), a journey jus (juris), right, law The term officious is used in a bad sense; an officious man is constantly interfering with what does not concern him. But in the root of the word there is nothing questionable or offensive. Offi-lacer, torn cium, in Latin, signifies duty. According to its derivation an laedo, I strike officious man is simply a man who attends to his duty. But even laesus, struck so pure a virtue may be carried to excess. Excessive and perverted lapis (lapidis), a stone the attention does become if it is outward rather than inward, more latus, carried apparent than real; if duty is a pretext or an excuse. A mis- latus, wide latus (lateris), a side understood sense of duty prompts even the sincere to meddle, and legatus, an ambassador in meddling they become officious. I subjoin two instances; in the legatio*, a gift first, officious is used in a good sense; in the second, it is used in a lego, I gather, read lenis, gentle levis, light bad sense : "Yet, not to earth are those bright luminaries Milton, "Paradise Lost." English Words. progeny, progenitor generation, degenerate glacial, glacier graduate, retrograde, ingredient, aggression retrogradation graminivorous gregarious, egregious homicide, human hosti hum iden inhume, exhume igni, igne ignition, igneous infern infernal insula реть inter, inti internal, intimate itiner it jac ject jug junct jur juris, juri jut juveni lacer lacerate The word progenitors has for its corresponding Saxon term forefathers; the term ancestors is used in nearly the same sense, only the latter simply points out those who have gone before us, our predecessors; the former includes the idea of descent; they of old were our progenitors, we are their offspring; they were our forefathers, we are their children or descendants. The word degenerate denotes that which has lost the qualities of the kind (genus, generis) or race. "The which thing declareth that men which have caste down their minds from the dignity of their nature, are so degenerat, and growen out of kinde, that thei seeme vtterly to be brute beastes."-Caluine, "Foure Godlye Sermons." To graduate is to take a degree or step in learning in one of the universities. On entering a university, a young man is said to matriculate (mater, a mother), because he becomes the child or pupil of the institution, which in regard to knowledge and discipline is his mother, After passing through a course of instruction, he, on proving fit and worthy by examination, takes a degree,—that is, by receiving certain tokens, as the privilege of putting after his name B.A. or M.A., which is the same as calling himself, in the one case, Bachelor of Arts, or, in the other case, Master of Arts, he is declared and made known as having made proficiency in a greater or less degree in university learning : "Invest me with a graduate's gown, 3mart. Midst shouts of all beholders, My head with ample square-cap crown, And deck with hood my shoulders." Egregious (from e, out of; and grex, a flock or crowd) denotes a person who is out of, that is, does not belong to, the multitude, one who is extraordinary and distinguished. Egregious is generally employed in a bad sense: "Thus have I adventured to expose the egregious folly, and to unmask the extreme corruption of heart, which assume the buffoon or the philosopher indifferently, to laugh at misery and death, and make a mockery both of law and religion."-Warburton. . Religion is here given as from ligo, I bind. This seems the best etymology. Viewed in this light religion is the source of obligation. Religion, placing man in immediate connexion with the Creator, deduces from that connexion men's obligations: first, to Gol, from whom they are; and next, to each other, whom for God's will, and God's sake, they are to love and serve. mislead and cheat ourselves. Delusions are substantial shows, presented in order to mislead; illusions are dreams and fancies which arise in an ill-regulated mind; the former are mostly dishonest, the latter are always weak; the former are preconcerted, the latter are spontaneous. PARSING AND COMPOSITION. For your exercise in parsing and composition take the ensuing letter of Mrs. Barbauld's. Give an account of every part of it as well as you can. Convert it into simple sentences. And having studied it carefully, close the book and write down from memory all you recollect of it. Then correct your copy by the original. Having done so, write a letter to a friend, if possible, on similar topics: 'July 28, 1803. "I am glad to find that you have spent the spring so pleasantly. But when you say you made the excursion instead of coming to London, you forget that you might have passed the latter end of a London winter in town, after enjoying the natural spring in the country. We have been spending a week at Richmond, in the delightful shades of Ham walks and Twickenham meadows. I never saw so many flowering limes and weeping willows as in that neighbourhood; they say, you know, that Pope's famous willow was the first in the country; and it seems to corroborate it, that there are so many in the vicinity. Under the shade of the trees we read Southey's Amadis,' which I suppose you are also reading. As all Englishmen are now to turn knights-errant, and fight against the great giant and monster, Buonaparte, the publication seems very reasonable. Pray are you an alarmist? One hardly knows whether to be frightened or diverted, on seeing people assembled at a dinner-table, appearing to enjoy extremely the fare and the company, and saying all the while, with a most smiling and placid countenance, that the French are to land in a fortnight, and that London is to be sacked and plundered for three days,-and then they talk of going to watering places. I am sure we do not believe in the danger we pretend to believe in; and I am sure that none of us can even form an idea how we should feel if we were forced to believe it. I wish I could lose, in the quiet walks of literature, all thoughts of the present state of the political horizon. My brother is going to publish Letters to a Young Lady on English Poetry;' Amen!' say I. Love to Eliza and Laura, and thank the former he is indefatigable. I wish you were half as diligent!' say you. for her note. I shall always be glad to hear from either of them. How delightful must be the soft beatings of a heart entering in o the world for the first time, every surrounding object new, fresh, and fair-all smiling within and without! Long may every sweet illusion continue that promotes happiness, and ill befall the rough hand that would destroy them!" LESSONS IN GEOLOGY.-No. XXV. By THOMAS W. JENKYN, D.D., F.R.G.S., F.G.S., &c. CHAPTER II. ON THE ACTION OF WATER ON THE EARTH'S CRUST. ON THE REPRODUCTIVE AGENCY OF RIVERS. RUNNING water has been shown to have a twofold power as a geological agent,- -a destructive power for the abrasion and excavation of rocks, and a transporting power for the removal of the particles and fragments which it had disintegrated. I now wish to show you what running water does with the materials which it has dislodged and held in suspension. It is almost a truism to remark, that what a stream removes from one place it deposits as a sediment in another. Your last lesson gave you illustrations of the fact, that the pebbles and gravel which a river brings down a steep declivity it leaves behind on the first plain which it reaches, and that it repeats this process on every declivity and plain which lie in its course towards the sea. To understand this agency geologically, throw your mind than any historical or traditional age. Suppose any rill or back to what is called geological time, that is, time far older torrent to start from its spring-head, for the first time after the hardening of the earth's crust; or, it may be, after the first elevation of the mountain, where the spring gushes out, above the level of the sea. The water will seek its level by running down the declivities, fissures, dells, or valleys, which it finds in Delusion and illusion though much alike both in derivation and the mountain range. How the dells or valleys which form the import, yet differ somewhat. The common idea is that of mislead-river-beds of the present day, originated is a difficult problem ing. By delusions others mislead and cheat us; by illusions we in geology, and will be considered in a future lesson. For the present, imagine a stream to gush from the mountain side,-to roll down the slopes of the naked rock,-to act chemically and mechanically in dissolving and abrading the surface of the rock, to bear the loosened materials in suspension in its current, and, finally, to deposit them, where its velocity has diminished, and especially where its waters come to a plain or level that would give them repose. The first flowing of the rill or little torrent will be in the bottom of a narrow fissure existing in the rock, such as is represented in the accompanying diagram, fig. 53. AA the wide chasm between high ridges of rocks. в the narrow fissure where a stream runs. The fissure, which B in this engraving represents, must be supposed to have the length of several miles, and to have variations of declivities, and level ground, as described in your last lesson. If the declivity of the fissure or valley be great and rapid, it is likely that the friction of a it, there is a tract of land eight miles long, a tract which consists altogether of the pebbles, and gravel, and mud, that the river has brought down from the Alps. On this tract, an ancient town is built, the present position of which gives us a clue to the measurement of the progress of this river deposition. The town Port Vallais was, eight hundred years ago, on the very edge of the lake, but in the course of these centuries, the Rhone has brought down to the lake so much detritus as to fill the upper end of it, so that now the town is a mile and a half inland. Fig. 53. B A broad Chasm or Valley in the Earth's Crust, and a narrow Fissure at its body of running water will scoop the surface, and make the If this fissure has the length of several miles, and if you like, of many scores of miles, it is likely that its bottom will, at many points, present a level surface or flats. On these flats or plains, the river will, as you have already learnt, leave and accumulate much of the pebbles and gravel which it had brought down from higher elevations. You can easily conjecture that, after depositing its first sediments along the breadth and the length of the first plain in its course, the river will continue to increase the amount of this deposit with every fresh abrasion or disintegration of the rocks in the higher part of its bed. The result of this repeated and continued process will be that, this part of the bed of the stream will rise by the detention and accumulation of sediments. It is probable that, at another spot along this fissure or ravine, the bottom, instead of being a level, may be greatly indented, so as to form a deep hollow, called geologically, a trough or basin. The river will, of course, contribute its waters until it has completely filled this trough, and finds an outlet. In this case the river has formed a lake, through which all its waters must in future pass. As the river passes through the lake, the solid matter which its current holds in suspension, will be deposited in it, until eventually the whole basin of the lake will be filled up with detritus of pebbles, gravel, and sand. If the rocky trough of the lake be large or long, even such lighter partic'es as make the water only turbid will have time to fall to B Our illustration of the deposition of sediments in a lake has hitherto supposed that only one stream flows into the trough. We must now proceed to another case, in which many torrents may be rushing into different parts of the lake, and filling up different portions of the basin. This process is represented by the annexed engraving, fig. 54. In this diagram, ▲ represents the principal river that feeds the lake, and which may be supposed to flow from a considerable distance, and to bring down a very large quantity of gravel into the lake. C and D are the short channels of two mountain streams which flow from the neighbouring heights on either side of the lake. B is the outlet of all the surplus waters of the three rivers. x and y are deltas formed at the entrance of the streams into the lake. I will explain the formation of these deltas in our next lesson. When these different rivers and torrents first reach the edge of the lake on their respective sides, their detritus sinks into deep water. All the heavier pebbles and gravel subside at once near the shore. The finer particles of mud are carried further out in the form of turbid water, which, being heavier than that of fresh water lakes, sinks gradually in clouds towards the bottom. These sediments become thicker and thicker with every fresh deposit, until, at length, they rise to the surface, appear first as marshes, and then as tracts of alluvial soil. In the course of ages these tracts become of considerable extent. In the meantime the detritus of different rivers are spread out further and further from the mouths of their respective rivers, and consequently nearer and nearer towards a common centre in Fig. 51, D the bed of the lake. On the supposition that this process be continued a sufficient length of time, the result will be that the entire basin of the lake will be completely filled up with these deposits which were for so long a time constantly approaching each other. For when the detritus washed down by A, C, and D had formed one tract of alluvium from c to D, the united detritus of the three rivers would be carried onward towards B, till the the bottom as a sediment or A Lake or Basin filling up by Alluvium of Rivers on opposite basin had ceased to be a lake. silt. Shores. This geological process is clearly and beautifully illustrated in the Lake of Geneva. | Where the waters of the Rhone enter that lake they are extremely turbid; but at Geneva, the other end of the lake, some good thirty miles lower down, they leave the lake as clear and transparent as a stream of crystal. The reason of this is, that the waters have left all their turbid materials widespread over the bottom of the lake. The case of the Lake of Geneva furnishes a very satisfactory illustration of the process by which alluvium is deposited by rivers. At the upper end of the lake, where the Rhone enters This accumulation of detritus at the mouth of each river, this gradual convergence of deposits towards a centre in the lake, and this final combination of all the sediments towards the lower end of the basin, illustrate some of the most remarkable phenomena found in the geological structure of the rocks of older series, which I will immediately explain. At this point, sum up the facts that have been stated. You have had a primitive fissure in the earth's crust, along which a stream of water flowed. In one part of the fissure there was a deep dent, trough, or basin, towards which several fissures and several rivers converged. The detritus washed down by the waters, has filled up the entire lake, and has formed a lovely alluvial plain. In this case, a new sedimentary rock has been formed, and the bed of the river has been raised to a higher level. Were you ever to have a geological section of the deposits of our imagined fissure, it would appear something like what is represented in our next diagram, fig. 55. This filling up of the basins of ancient lakes is no geological fancy. It has taken place in thousands of instances. When, in your own country, you travel through mountainous districts, and find, in the bosom of rocky hills, verdant glens and fertile bottoms, they are, in most cases, rocky basins or lakes filled up with rich alluvial soil, which has been transported thither by the stream that runs through them. If you ever ascend the valley of any river of some length, you will find that it consists of a succession of such basins, one on a higher level than the other, each of them separated by a rocky gorge that was once the barrier of the lake. The fact that explains them all is, that the river has filled the different basins or lakes, one after another, and has partially cut through the rock that formed the barrier which it is still gradually scooping to a greater depth. numerous soundings, it has been ascertained that, everywhere, the bottom consists generally of a very fine and adhesive clay, but which is of different colours in different parts of the lake. In one district the clay is blue, in another red, and in a third white, hardening into a substance like pipe-clay. This is accounted for by the separate character of the different rocks from which the rivers bring down detritus. The study of fig. 55 will help you to understand the stratification of sedimentary rocks. You have scarcely ever taken a fragment of free sandstone in your hand without perceiving that it is laminated almost like the leaves of a book, and that sometimes the lamina have different colours. Some portions of these stratifications are a conglomerate of various-sized pebbles; others are laminated sands; and others are thinly foliated clays or shales. This diversity in the structure of the stratification is occasioned by the variations in the velocity of the river at different times of the year. Its current has not always the same power to sweep particles of certain weight and dimensions over a large extent of surface. As the force of the current augments or decreases, the materials are borne and scattered or limited to particular places, and are sorted according to their forms, dimensions, and weight. These natural divisions, which are observed in the stratification, are also occasioned by the intervals of time which may transpire between the different seasons of periodical rains, of melting of snows, and of other agencies, which may occasion Fig. 55. I have intimated that an examination of the composition of the sediments which have filled up the deep hollows of mountain fissures, and which have obliterated several lakes, enable us to comprehend the lithological structure of some older rocks. It is constantly found that some of these ancient sedimentary rocks, though they are of the same age and formation, vary exceedingly in the character of their materials, the size and structure of their pebbles and gravels, and in the colour and texture of their sands and clays. These diversities are satisfactorily explained, when you consider the facts and the processes represented by fig. 54. Imagine the outline of fig. 54 to repersent the basin of an immense lake-say Lake Superior, in North America, which is The Basin of a Lake in a Mountain Fissure, now filled up with alluvium in is the largest body of fresh water in the world. The surface These finer particles of detritus seem to have been spread over the whole breadth and length of the bottom of the lake. By floods in a river. It is possible that the sediments deposited at one flood may have acquired a consider able degree of consis tency and hardness, before the silt of another flood will be precipitated in layers upon the surface of the preceding bed. There may also be a great variety of circumstances occurring periodically which will occasion some variations either in the colour or in the fineness of the articles deposited, and indeed in both. Such variations will again give rise to alternations of strata which are distinct from each other, both in mineral ingre dients and in mechanical texture. It would be endless to enumerate all the circumstances which may contribute to such variations and alternations of strata in the same rock. At one time there may be a sudden flood, when the velocity of the turbid current will be in greatest force, and when it will bear along pebbles and sand which it will spread over a large area, on the top of which, when the waters are low and less agitated, the finer materials will settle as a sediment of sand or clay. At another period there may be excessive rains and extensive inundations, which will carry down soft mud and drifted wood and animals, and thus form a rock of a character very different from that of the underlying stratum. At different periods the several streams also, as represented in fig. 54, may be charged with several materials respectively. One river may be charged with calcareous matter from linestone rocks; a second, with argillaceous matter from slate formations; a third may wash down sand and gravel; and s fourth brings down impalpable mud. These variations and alternations may be repeated with much regularity, until a bed of rocks several scores of feet in thickness may be formed in alternating beds of different colour and of distinct chemical structure. Bernard Palissy, fut le premier qui, vers le milieu du seizième siècle, osa dire que les coquilles fossiles n'étaient pas des jeux de la nature, mais qu'elles avaient été déposées par la mer dans les localités où elles se trouvent aujourd'hui. |