MORE THOUGHTSON APEBBLE.

BRIGHTON CLIFFS.

Now we must bear in mind, that had the chalk remained at the bottom of the deep sea in which it was originally deposited, it would not have been exposed to these destructive operations. It is therefore manifest, that at some very distantperiod of the earth's physical history, the bed of the Chalk-ocean was broken up, extensive areas were protruded above the waters, lines of sea-cliffs were formed, and boulders, sand, and shingle accumulated at their base. Subsequent elevations of the land took place, and finally, the sea-beach was raised to its present situation, which is several hundred feet above the level of the sea!

Every part of the earth's surface presents unequivocal proofs that the elevation of the bed of the ocean in some places, and the subsidence of the dry land in others, have been, and are still, going on; and that, in truth, the continual changes in the relative position of the land and water, are the effects of laws which theDivine Author of the Universe has impressed on matter, and thus rendered it capable of perpetual renovation:—

Art, Empire, Earth itself, to change are doomed;Earthquakes have raised to heaven the humble vale,And gulfs the mountain's mighty mass entombed,And where the Atlantic rolls wide continents have bloomed.

Beattie.

IMMUTABILITY OF THE SEA.

Our noble poet, Lord Byron, in his sublime apostrophe to the Sea, has most eloquently enunciated the startling fact revealed by modern geological researches,—namely, that if the character of immutability be attributable to anything on the surface of our planet, it is to the ocean and not to the land!—

Roll on, thou deep and dark blue ocean—roll!Ten thousand fleets sweep over thee in vain;Man marks the earth with ruin—his controulStops with the shore:—upon the watery plainThe wrecks are all thy deed, nor doth remainA shadow of man's ravage, save his own.When, for a moment, like a drop of rain.He sinks into thy depths with bubbling groan,Without a grave, unknell'd, uncoffin'd, and unknown!Thy shores are empires, changed in all save thee,—Assyria, Greece, Rome, Carthage, what are they?Thy waters wasted them while they were free,And many a tyrant since; their shores obeyThe stranger, slave, or savage,—their decayHas dried up realms to deserts:—not so thou,Unchangeable, save to thy wild waves' play—Time writes no wrinkle on thine azure brow:Such as Creation's dawn beheld, thou rollest now!

Thy shores are empires, changed in all save thee,—Assyria, Greece, Rome, Carthage, what are they?Thy waters wasted them while they were free,And many a tyrant since; their shores obeyThe stranger, slave, or savage,—their decayHas dried up realms to deserts:—not so thou,Unchangeable, save to thy wild waves' play—Time writes no wrinkle on thine azure brow:Such as Creation's dawn beheld, thou rollest now!

Thou glorious mirror, where the Almighty's formGlasses itself in tempests; in all time,Calm or convulsed—in breeze, or gale, or storm,Icing the Pole, or in the torrid climeDark-heaving, boundless, endless, and sublime—The image of Eternity—the throneOf the Invisible; even from out thy slimeThe monsters of the deep are made; each zoneObeys thee: thou goest forth, dread, fathomless, alone!

Childe Harold.Canto IV.

APOSTROPHE TO THE OCEAN.

I will conclude this "first lesson" with the following beautiful remark of an eminent living philosopher:[J]—"To discover order and intelligence, in scenes of apparent wildness and confusion, is the pleasing task of the geological inquirer; who recognises, in the changes which are continually taking place on the surface of the globe, a series of necessary operations, by whichthe harmony, beauty, and integrity of the Universe are maintained and perpetuated; and which must be regarded, not as symptoms of frailty or decay, but as wise provisions of the Supreme Cause, to ensure that circle of changes, so essential to animal and vegetable existence."

[J]Dr. Paris.

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"Not a mote in the beam, not an herb on the mountain, not a pebble on the shore, not a seed far-blown into the wilderness, but contributes to the lore that seeks in all the true principle of life—the beautiful—the joyous—the immortal."

SirE. Bulwer Lytton'sZanoni.

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More thoughts on a pebble!—is not the subject exhausted? have not all the hieroglyphics impressed on the flint been interpreted?—can Science, like the fabled wand of the magician, call forth from the stone and from the rock their hidden lore, and reveal the secrets they haveso long enshrined?—Gentle Reader! but one page of the eventful history of the pebble has been deciphered; I proceed to transcribe this natural record of the past, explain its mysterious characters, and present to thy notice the marvels they disclose.

Our previous examination of the specimen showed that the flint had once been in a fluid state, and had consolidated in a sea inhabited by shells, echini, fishes, corals, sponges, and other zoophytes; and the appearance of the fractured end (Plate I, c), indicated that some organic body had formed the nucleus of the pebble, and that traces of the structure of the original still remained. To ascertain if this inference is correct, it will be necessary to divide the stonein a longitudinal direction—but I will first strike off a small fragment, and examine it by the aid of a microscope.

FOSSIL ANIMALCULES.

Lign. 10:—Fossil animalcules (Xanthidia) in Flint.

By a sharp blow of a hammer, a very thin and minute portion of the flint has been detached (seeLign. 10, fig. 1); it is translucent, and when held between the eye and a strong light, appearslike a slice of horn; and a few extremely minute specks may with difficulty be detected. Under the microscope, five of these almost invisible points are well defined, and present a radiated appearance (seefig. 3); but I will substitute a higher power, and lo! they are seen to be distinct globular or spherical bodies beset with spines (fig. 3); and with a still more powerful lens, one which magnifies many hundred times, their nature is completely displayed. The whole five possess this general character—a central globular case or shell, from which radiate tubes or hollow spines, that terminate in fringed or divided extremities (figs. 4, 5, 6); but these bodies differ from each other in the relative proportions of the shell and spines, and inthe number, shape, and length of the tubular appendages. The group, in short, is separable into three distinct species, of the same kind of fossil remains; and several other varieties occur in the chalk and flint. .

XANTHIDIA IN FLINT.

Lign. 11:—Xanthidium palmatumin flint: highly magnified.

But what are these bodies?—They are the durable cases of animalcules, many species ofwhich swarm in our seas, and are so minute, that thousands may be contained in a drop of water! In a living state, the case is flexible and filled with a granular jelly, which is the soft body of the animalcule, and the tubes and the outer surface are invested with a similar substance. After death the soft parts dissolve; but the case and its spines often remain unchanged.

In another magnified portion of the pebble, a specimen of the microscopic discoidal shells which we have already seen compose the greater part of the white chalk (Lign. 5, p. 14), is beautifully displayed when viewed by transmitted light, under a highly magnifying power (Lign. 12).[K]Our investigation has thus shown, that a great partof the pebble is actually composed of the aggregated fossil remains of animalcules, so minute as to elude our unassisted vision, but which the magic power of the microscope reveals to us, preserved, like flies in amber, in all their original sharpness of outline and delicacy of structure.

[K]Note VI.Rotaliæ in chalk and flint.

ROTALIA IN FLINT.

Lign. 12:—Rotalia in flint: highly magnified.

On another fragment of this stone twoglittering specks, not larger than a pin's head, are discernible (Lign. 9): these with a magnifier of moderate power, are seen at a glance to be scales of fishes. But they differ from each other; both have the surface smooth, and without enamel: in the one the margin or edge is simple (fig. 3); in the other, it is divided like the teeth of a comb (fig. 2);—trifling as this difference may appear, it is sufficient to enable the naturalist to determine that the fishes which furnished these scales belonged to two distinct orders, of which the Salmon and the Mullet are living examples.

Lign. 13:—Scales of Fishesin flint.Fig.1.—A fragment of the pebble with the scales of the natural size.2.—One of the Scales (of a species ofBeryx) highly magnified.3.—The other Scale (of a species ofSalmo).

Plate II.Longitudinal section of the Pebble.Page 41.

Plate II.

Longitudinal section of the Pebble.Page 41.

Page 41.

SECTION OF THE PEBBLE.

Plate II

We will now avail ourselves of the assistance of the lapidary, and divide the pebble in a longitudinal direction;—what a beautiful and interesting section is thus obtained! The markings observable on the fractured portion of the stone (seePlate I, c), are thus shown to have originated, as we surmised, from some organic body,which the flint, when fluid, had penetrated and enveloped. The enclosed fossil was obviously one of those soft marine zoophytes, allied to theActiniæorSea-Anemones, which are of a globular, spherical, or inversely conical shape, and consist of a tough, jelly-like substance, permeated with tubes, disposed in a radiated manner around a central cavity, or digestive sac; a structure admitting of that constant supply and circulation of sea-water, which the economy of these curious forms of animal existence requires.

ISLE OF WIGHT PEBBLES.

The surface exposed by the division of the pebble, is an oblique vertical section of the petrified zoophyte. It shows a central canal filled with bluish-grey flint (Plate II, c), in a mass traversed by tubes or channels, which possessconsiderable beauty and variety of colour from an impregnation of iron.[L]A transverse section (seeLign. 14.fig. 1) would, of course, have a central spot, with rays proceeding thence to the circumference, as in the oblique fracture (Plate I, c).[M]

[L]Specimens of this kind form beautiful objects when polished, and are mounted as brooches by the lapidaries of Brighton, Bognor, and the Isle of Wight, who term them petrified sea-animal flowers. Mr. G. Fowlstone (4, Victoria Arcade) of Ryde, has many splendid examples, and also agates and jaspers, the genuine productions of the Island.

[M]Note VII.Isle of Wight Pebbles.

CHOANITES KONIGI.

The form of the original zoophyte when living, must have been that of an inverted cone or funnel, (hence the scientific nameChoaniteor funnel-like,) with a long cylindrical digestive cavity in the centre, from which tubes ramified throughevery part of the mass. It was attached to a rock, stone, or shell, by root-like fibres which spread out from its base; and its soft body was strengthened, as is the case in many sponges and animals of a similar nature, by numerous siliceous spines or spicula, which are often found in the flint and chalk (seeLign. 10.fig. 5).[N]

[N]Note VIII.Zoophytes of the Chalk.

Lign. 14:—ChoanitesKonigi: from theChalk.Fig.1.—A transverse section.2.—Upper portion of the body.3.—Vertical section, like the pebble,Pl. II.p. 41.4.—A flint, enclosing a Choanite, which is exposed on the upper surface.5.—Various forms of siliceous spines of Choanites and other analogous bodies; magnified slightly.(See 'Medals of Creation,' p. 264.)

TheChoanitesmust have swarmed in the Chalk ocean, for in some of the strata almost every flint exhibits traces of these zoophytes.[O]

[O]The shingle at Brighton and Bognor in Sussex, and in various localities in the Isle of Wight, abounds in specimens more or less perfect. I would inform my fair readers who may visit these places, and be inclined to purchase a brooch, in illustration of these "Thoughts on a Pebble," that by far the greater number of the so-called Brighton and Isle of Wight moss-agates, jaspers, &c., sold by the lapidaries and jewellers, are of German or Scotch origin; and that thefalse-emeralds, andaquamarines, are water-worn fragments of common green glass bottles!

CORALS IN CHALK.

Lign. 15:—Branch ofCoralon the Pebble.Fig.1.—A portion magnified.2.—A fragment represented as when alive.a, a, Two polypes collapsed.b, b, Two polypes with their tentacula extended.

One more character inscribed on the pebble remains to be interpreted; it is the minute branch of coral partially imbedded in the flint.[P]The surface of this coral, when seen with a powerful lens, is found to be studded with small pores or cells. In a recent state, each cell was inhabited by a living polype or animalcule, which, though permanently united at its base to thegeneral mass, had an independent existence, and possessed sensation and voluntary motion; expanding its thread-like feelers or tentacula to catch its prey, and withdrawing, at will, into its little cell.[Q]

[P]Plate Iimmediately below the shell and spine of Echinus.[Q]For a popular account of recent and fossil corals, see 'Wonders of Geology,' 6th Edit., vol. ii. Lecture VI. p. 589.

[P]Plate Iimmediately below the shell and spine of Echinus.

[Q]For a popular account of recent and fossil corals, see 'Wonders of Geology,' 6th Edit., vol. ii. Lecture VI. p. 589.

Lign. 16:—A Coral-polype preserved in flint: magnified 500 diameters.

From these investigations, we learn that the Pebble, which has formed the subject of our contemplation, had its origin in a living zoophyte that was growing on a rock, in a sea whose boundaries have long since been swept away; that corals, shells, and echini inhabited the bottom of the deep; and that fishes related to existing families, sported in the waters of that ancient ocean. In fine, we have presented to us the scene so exquisitely described by the American poet:—

THE CORAL GROVE.

Deep in the waves is a coral grove.Where the purple mullet and gold fish rove,Where the sea-flower spreads its leaves of blue,That never are wet with the falling dew.But in bright and changeful beauty shine,Far down in the green and glassy brine.The floor is of sand, like the mountain drift.And the pearl-shells spangle the flinty snow;From coral rocks the sea-plants liftTheir boughs, where the tides and billows flow;The water is calm and still below.For the winds and the waves are absent there,And the sands are bright as the stars that glowIn the motionless fields of upper air:There with its waving blade of green,The sea-flag waves through the silent water,And the crimson leaf of the dulse is seen.To blush like a banner bathed in slaughter.There with a light and easy motionThe fan-coral sweeps through the clear deep sea;And the yellow and scarlet tufts of ocean,Are bending like corn on the upland lea;And life in rare and beautiful forms,Is sporting amidst those bowers of stone.

Percival.

Lign. 17:—Minute Corals from the Chalk;[R]highly magnified.[R]Note IX.Minute corals from the Chalk.

Lign. 17:—Minute Corals from the Chalk;[R]highly magnified.

[R]Note IX.Minute corals from the Chalk.

MICROSCOPIC CORALS.

Our previous examination of the pebble had prepared us for these results; but the microscope, that mighty talisman of wisdom, has shown us, that even those infinitesimal creaturesto whom a drop of water is an unbounded ocean—those living atoms of that world of being which is for ever concealed from the uninstructed mind—the inhabitants of that universe beneath us, which the eye of science can alone penetrate, existed in ages incalculably remote, and were, like their gigantic contemporaries, the living instruments by which a large proportion of the solid materials of the surface of our planet was elaborated; their imperishable siliceous and calcareous skeletons, constituting no inconsiderable amount of the crust of the earth.[S]

[S]See"Thoughts on Animalcules, or a Glimpse of the Invisible World revealed by the Microscope," by the Author. Published by Mr. Murray, London, 1846.

Fossil animalcules and corals similar to thosewe have discovered in the pebble and in the chalk, and hundreds of other genera and species equally minute, occur in such prodigious numbers, as to warrant the conclusion, that this class of animal existence has contributed more largely than any other, to the formation of the sedimentary strata.

Not only the Chalk hills, but whole mountain-ranges formed of other deposits of great thickness and extent, are found to consist almost entirely of similar remains. In the state of rock, of sand, of clay, of marl—in the coarsest limestone, and in the purest crystal, the petrified skeletons of animalcules alike abound. The town of Richmond, in Virginia, is built on a bed of stone twenty feet thick, which is wholly composed of the fossilskeletons of different kinds of marine animalcules. The polishing slate of Bilin, in Germany, is wholly made up of the siliceous shields of similar beings, disposed in layers without any connecting medium; and these belong to species so minute, and are so closely compressed together, that in a cubic inch of the stone, weighing but two hundred and twenty grains, there are the remains offorty-one thousand millionsof animalcules![T]

[T]See 'Medals of Creation,' p. 221.

Lign. 18:—Animalcules from the Richmond earth: very highly magnified

[U]Note X.Richmond Infusorial earth.

REFLECTIONS.

Here we must bring our "Thoughts on a Pebble" to a close; but not without adverting to the pure and elevating gratification which investigations of this nature afford, and the beneficial influence they exert upon the mind and character. In circumstances where the uninstructed and incurious eye can perceive neither novelty nor beauty, he who is imbued with a taste for natural science will everywhere discoveran inexhaustible mine of pleasure and instruction, and new and stupendous proofs of the power and goodness of the Eternal! For every rock in the desert, every boulder on the plain, every pebble by the brook-side, every grain of sand on the sea-shore, is fraught with lessons of wisdom to the mind which is fitted to receive and comprehend their sublime import.

"From millions take thy choice,In all that lives a guide to God is given;Ever thou hear'st some guardian angel's voice,When nature speaks of heaven!"

Amidst the turmoil of the world and the dreary intercourse of common life, we possess in these pursuits a never-failing source of delight, of which nothing can deprive us—an oasis in the desert, to which we may escape, and find a home"wherever the intellect can pierce, and the spirit can breathe the air."[V]For like the plant which the Prophet threw into the waters of Marah,[W]that changed the bitterness of the wave into sweetness, a branch from the tree of knowledge thrown into the turbid stream of life, purifies its waters, and imparts to them a healing virtue, which sheds a hallowing and refreshing influence over the soul!

[V]Sir E. Bulwer Lytton.[W]Exod.XV.23.

[V]Sir E. Bulwer Lytton.

[W]Exod.XV.23.

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(SeePage 22.)

FROM SKETCHES IN PROSE AND VERSE,

By the late G. F. Richardson, Esq.

The Nautilus and the AmmoniteWere launch'd in storm and strife;Each sent to float, in its tiny boat,On the wide, wild sea of life.And each could swim on the ocean's brim,And anon, its sails could furl;And sink to sleep in the great sea deep,In a palace all of pearl.And their's was a bliss, more fair than this,That we feel in our colder time;For they were rife in a tropic life,In a brighter, happier clime.

The Nautilus and the AmmoniteWere launch'd in storm and strife;Each sent to float, in its tiny boat,On the wide, wild sea of life.

And each could swim on the ocean's brim,And anon, its sails could furl;And sink to sleep in the great sea deep,In a palace all of pearl.

And their's was a bliss, more fair than this,That we feel in our colder time;For they were rife in a tropic life,In a brighter, happier clime.

They swam 'mid isles, whose summer smilesNo wintry winds annoy;Whose groves were palm, whose air was balm.Where life was only joy.They roam'd all day, through creek and bay,And travers'd the ocean deep;And at night they sank on a coral bank,In its fairy bowers to sleep.And the monsters vast, of ages past.They beheld in their ocean caves;And saw them ride, in their power and pride,And sink in their billowy graves.Thus hand in hand, from strand to strand,They sail'd in mirth and glee;Those fairy shells, with their crystal cells,Twin creatures of the sea.But they came at last, to a sea long past,And as they reach'd its shore,The Almighty's breath spake out in death,And the Ammonite liv'd no more.

They swam 'mid isles, whose summer smilesNo wintry winds annoy;Whose groves were palm, whose air was balm.Where life was only joy.

They roam'd all day, through creek and bay,And travers'd the ocean deep;And at night they sank on a coral bank,In its fairy bowers to sleep.

And the monsters vast, of ages past.They beheld in their ocean caves;And saw them ride, in their power and pride,And sink in their billowy graves.

Thus hand in hand, from strand to strand,They sail'd in mirth and glee;Those fairy shells, with their crystal cells,Twin creatures of the sea.

But they came at last, to a sea long past,And as they reach'd its shore,The Almighty's breath spake out in death,And the Ammonite liv'd no more.

And the Nautilus now, in its shelly prow,As o'er the deep it strays,Still seems to seek, in bay and creek,Its companion of other days.And thus do we, in life's stormy sea,As we roam from shore to shore;While tempest-tost, seek the lov'd—the lost—But find them on earth no more!

And the Nautilus now, in its shelly prow,As o'er the deep it strays,Still seems to seek, in bay and creek,Its companion of other days.

And thus do we, in life's stormy sea,As we roam from shore to shore;While tempest-tost, seek the lov'd—the lost—But find them on earth no more!

Geology, in the magnitude and sublimity of the objects of which it treats, ranks next to Astronomy in the scale of the sciences.

SirJ. F. W. Herschel.

fossils, tools and map

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The shells of mollusca, in consequence of their durability, are the most abundant fossils in the sedimentary strata;[X]entire layers of marble and other limestone, of great thickness and extent, are wholly composed of an aggregation of a few species or genera: in some instances of fresh-water snails—as, for example, the Sussex and Purbeck marbles;[Y]in others, of marine bivalves and univalves, as the oyster-conglomerate of Bromley, and the shelly limestones of Portland, Dorsetshire, &c.

[X]For an account of the geological value of fossil shells, see 'Medals of Creation,' vol. i. p. 363.

[Y]See 'Wonders of Geology,' 6th Edition, p. 402.

The cretaceous strata contain many hundred species of bivalves and univalves, by far the greater part of whichbelong to extinct genera; and the species, with but four or five exceptions, are unknown in more recent deposits. In loose sandy strata, fossil shells are oftentimes beautifully preserved, and may be obtained in as perfect a condition as if gathered from the sands on the sea-shores: such is the state of the specimens which abound in the sandy clays near Barton in Hampshire, and in the "Crag" of Essex and Suffolk. In certain beds of clay, shells are also found entire; sometimes retaining the epidermis, and the cartilaginous ligament of the hinge. The bivalves in the white chalk are generally perfect; but the univalves, probably from the more delicate structure of the originals, seldom retain any vestiges of the shell, excepting portions of the internal nacreous coat adhering to the chalk casts, which have been moulded in the interior of the shells.

Lign. 19:—Bivalve shells (Terebratulæ) from Chalk (natural size).1, 2. Plicated species. 1.T. octoplicata.2.T. subplicata.3, 4. Smooth species. 3.T. semiglobosa.4.T. subrotunda.

TEREBRATULÆ FROM CHALK.

In some of the cretaceous strata several extinct species ofOyster,Scallop,Arca,Tellina, and other well-known marine bivalves abound; and with them are associated many genera of which no living species have been observed. Among the bivalves that prevail in the English chalk, are three or four kinds ofTerebratulæ: which are small, elegant, subglobular shells, belonging to a familyof which nearly 500 species, referable to several genera, have been obtained from the British strata.[Z]Certain genera are restricted to the most ancient sedimentary rocks, in which they occur in almost incredible numbers; others have a wider range and are met with in the later secondary deposits; while a few are found in the newest beds, and have living representative species in the seas of warm climates. From the immense antiquity of their lineage, theseTerebratulæhave been humourously termed the "fossil aristocracy." Some of the most common chalk species are figured of the natural size inLign. 19. When living the animal was attached to a rock or other body by means of abyssusor peduncle, exserted through the aperture in the beak or curved extremity of the largest valve.[AA]The shells of the smoothTerebratulæare full of minute holes or perforations, which may readily be distinguished with a lens of moderate power.

[Z]See 'Wonders of Geology,' 6th Edit. p. 329.[AA]In the Conchological Gallery of the British Museum there is a group of thirty or forty recentTerebratulæattached to a stone by their peduncles; from Australia.

[Z]See 'Wonders of Geology,' 6th Edit. p. 329.

[AA]In the Conchological Gallery of the British Museum there is a group of thirty or forty recentTerebratulæattached to a stone by their peduncles; from Australia.

PETRIFIED OYSTER.

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