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table skeletons; and so do, also, the calyces of the henbanc, of all the campanula or bell-flower tribe, of the winter cherry,

&c.

Put the leaves into an earthern or glass vessel, pour a large quantity of rain water over them, and expose them, uncovered, to the action of the air, and the heat of the sun. As the water evaporates and the leaves become dry, more water must be added, and in this they must continue for six weeks or more. When they have been for some time in a putrescent state, the two membranes of the leaf will begin to separate, and the green part to become fluid, a proof that the operation of clearing may now be performed.

To do this the leaf is to be put on a flat earthern plate, and being gently squeezed with the finger, the membranes will begin to open, and the green substance to come out at the edges, requiring the membranes to be taken off very carefully, and great caution to be used in separating them near the middle ribs. When once there is an opening towards this separation, the whole membrane always follows easily. The leaves now require to be washed clean and bleached, which last process is very simple. Place them, first damped, in a close box, along with a little brimstone burning in a pan or ladle, and in an hour they will be very white. It should be remembered that there will be no success if the water is often changed, and that the more leaves done at the same time the better.

Fruits are divested of their pulp in a different way. Take, for example, a fine large pear which is not tough, but soft; let it be neatly pared without squeezing it, and without injuring either the crown or the stalk, put it in a pot of rain water, cover it, set it over the fire, and boil it gently till it is perfectly soft. Then take it out, lay it in a dish filled with cold water, and holding it with one hand by the stalk, rub off as much pulp as you can with the finger and thumb, beginning at the stalk, and rubbing regularly towards the crown. The fibres are most tender towards the extremities, and therefore in these directions require greater care. Any pulp now sticking to the core may be removed by the point of a fine penknife. In order to see how the operation advances, the water should frequently be thrown away, that clear water may be substituted. When the pulp is removed, the remainder should be placed in spirits of wine. The fibres that will thus be presented to the eye exhibit a very remarkable and beautiful structure. The same process may be pursued with the bark of trees, with a similarly interesting result.

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the G is a note which a singer would naturally introduce as a connecting link between the F and the A, so as to give roundness and smoothness to the melody. Neither of these notes in connexion with the under part gives

the smallest offence to the ear. In the second passage, the F in the under part, which forms a dissonance with G in the upper, is a note of suspension, introduced to avoid the bad effect which would otherwise be produced by the consecutive fifths pointed out by our correspondent. The passage in its elementary form would be

ANSWERS TO CORRESPONDENTS.

AUTOMATHES (Morriston): See vol. I. p. 288, col. 2, line 49.-PHILOSOPHICAL (Bamber-bridge): We question the fact.-A LABOURER (St. Osyth): We have no space to continue the argument.-WOULD-BE GRAINER: We do not know.-P. D. (Dover): See vol. I. p. 271, col. 1.-G. S—TT (W-n): The old names.-J. K. S. (Belfast): Right.-J. W. GARLICK (Halifax): Kuhner's Elementary Greek Grammar.-C. HILL (Kensington): Right.-A. CAMPBELL (Cathcart): The first question has been already proposed.-S. EVANS (Merthyr Tydfi): We wish he had given us the name of the worthy chancellor, and the printed work where the extract is to be found.-IZAK (Leicester): Very good, but not quite equal to the proposer's solution.-W. II. MANNING (Lewisham): His kind communication is under consideration.-T. HOLLINSHED (Somer's-town): Right -J. E. A. R. (Salford): The letters explain the notes in music.-LIONI (Cork): Very well; but he should have had L'Educateur Populaire instead of the English words. Johnson says that Salmagundi is a corruption of the Latin Salgama, preserves or pickles. The French have it Salmigondis.-J. H. W. (Melbourne): Verbs ending in izo in Greek, are frequentatives, like Latin verbs ending in ito. Thanks for his opinion on Phrenotypics.-W. C. (Chelsea): See vol. I, p. 288, col. 2, line 49.-I. O. U.: Interest Tables are frequently wanted; we would recommend application to a banker or broker.-R. REED (Doncaster): Fowne's Rudimentary Chemistry.

A BUILDER'S CLERK (Ipswich): We cannot answer his queries because we have not decided on all the points. He will find by consulting the Times advertisements that catalogues of second-hand books are forwarded gratis by many London booksellers.-J. C. EWAN (Bootle) should study the two branches he likes best most carefully, and read all the others for relaxation. DISCIPULUS (Glasgow): Wrong.-W. E. (Bristol): We have not seen the book he mentions.-PUPIL TEACHER (Scremerston): Right in the solutions. Disintegration is the opposition of integration; the latter means a making whole, a restoring all parts; the former, therefore, means a destroying of the wholeness, a reduction to parts.-F. E. FLETCHER (Cheltenham): Such queries as his must in future be referred to the editor of the "Pathway." ATHOS (Newcastle): The answer to the snail query is 16 days. Perhaps the glowworm was an ignis fatuus.—A FACTORY LAD (Wardle): His inquiry about the Normal-school will be answered. His derivation of mill shows ingenuity, but it is a Saxon word; see Johnson's Dictionary.-M. W. N. (Manchester): At the extinction of the Roman Empire, which, according to Gibbon, took place at the death of Theodosius, "Arcadius and Honorius saluted of the East and the eastern ing the Prefectura Orientis et Iiliryci, was allotted to Arcadius, and the western empire, comprising the Prefectura Galliarum et Italiæ, to

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The fifths here would be glaring, but the introduction of the—an accented note, which suspends the c-removes the bad effect which they would otherwise produce. The other case of supposed error is not copied in our duced by notes which do not belong to the fundamental chorde-suspensions, correspondent's note. Many of the finest effects of part-writing are pro anticipations, and passing notes. But they must be cautiously and discreetly used; otherwise (as in much of the modern German music), they may be harsh and unpleasing. As to consecutive fifths, there are innumerable exceptions to the rule whereby they are prohibited-exceptions pointed out in every good treatise on harmony."

LITERARY NOTICES.

THE ALTAR OF THE HOUSEHOLD; or, DOMESTIC WORSHIP. Part 1. will be published on the 1st of January, 1853, price 1s. This work will con tain a Series of Services for the Family, adapted for every morning and ever ing throughout the year, viz., portions of Scripture, Prayers and Thanks givings, suitably adapted to each other, to which will be added short prac tical comments to explain the subjects read, or enforce the duties enjoined. This work will be edited by the Rev. Dr. Harris, Principal of New College, assisted by a band of eminent divines in London and the country.

THE SELF AND CLASS EXAMINER IN EUCLID, containing the Enuncia tions of all the Propositions and Corollaries in Cassell's Edition, for the use of Colleges, Schools, and Private Students, is now ready, price 3d. is now ready, price ls. in stiff covers, or 1s. 6d. neat cloth. CASSELL'S ELEMENTS OF ARITHMETIC (uniform with Cassell's EUCLID),

THE ANSWERS TO ALL THE QUESTIONS IN CASSELL'S ARITHMETIC, for the use of Private Students, and of Teachers and Professors who use this work in their classes, is preparing for publication.

Price 1s., beautifully printed, super-royal 8vo., MEMENTO FOR 1853.-The most complete work on the question of slavery THE UNCLE TOM'S CABIN ALMANACK; or, THE ABOLITIONIST that has hitherto been published. Everybody who has read "Uncle Tom's Cabin" should possess themselves of a copy of this book, which more than verifies all the statements in Mrs. Stowe's thrilling narrative. This work is splendidly Illustrated by George Cruikshank, Esq.; J. Gilbert, Esq.; W. Harvey, Esq.; H. K. Browne, Esq. ("Phiz"); and other eminent artists; and contains upwards of 70 pages super-royal 8vo., replete with the most stirring incidents-Lives of Escaped Negroes; the Workings of the Fugitive Slave American Slavery. The sale already is very large, 30,000 copies baring Law; Anecdotes, Narratives, and Historical and Descriptive Accounts of been disposed of within three weeks.

ILLUSTRATED EXHIBITOR ALMANACK, Thirty splendid Engravings, Gd. POPULAR EDUCATOR ALMANACK, Notices and Essays on Education, 3d. TEMPERANCE ALMANACK, Tale by the Authoress of Uncle Tem, &c., d. PROTESTANT DISSENTERS' ALMANACK, with new Historical Notices, &c. d. Printed and Published by JOHN CASSELL, La Belle Sauvage Yard, Ludgate hill, London. December 11, 1852.

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composed or disintegrated, to be removed by currents, to be carried away to a lower level, and finally to be deposited in some river, pool, lake, or the sea.

A running stream necessarily combines in its action the two powers of water. By infiltration into the mass of a rock, it tends to separate the particles of which it is composed. In this process, it acts chemically on the cementing matter that made the rock hard, and, by dissolving it, sets its particles at liberty. Its mechanical power then dislodges these particles, and forces them away from the surface on which it acts. When these particles have been removed from the surface, the rock presents to the running water a fresh surface, which, in its

VOL. II.

In the volcanic districts of Auvergne, in Central France, there are many examples of valleys, across which streams of lava have, at some ancient period, flowed, and, on cooling, have formed a high embankment or dam, which has completely stopped the course of the river at the bottom. These lava embankments furnish the most clear instances of the abrading power of running water. The rivers that have been stopped, collected their waters, and then have cut out and cut downwards for themselves fresh passages, which now appear as large chasms in the lava, some of them from twenty to seventy feet in depth, and frequently of great breadth.

The materials on the surface of the sides of these valleys, 38

table skeletons; and so do, also, the calyces of the henbane, | Honorius. The East included Asia, Egypt, Lybia, Thrace, Mosia, Macedonia, of all the campanula or bell-flower tribe, of the winter cherry, the islands of Sicily, Sardinia, and Corsica, Spain and the Balearic Isles, Grecce, and Crete. The West included Italy, countries south of the Danube,

&c.

France, Switzerland, Germany, and Britain.

Put the leaves into an earthern or glass vessel, pour a large
quantity of rain water over them, and expose them, uncovered,
to the action of the air, and the heat of the sun. As the
water evaporates and the leaves become dry, more water must
be added, and in this they must continue for six weeks or more.
When they have been for some tim
*rescent state, the
two membranes of the leaf
ate, and the
of clear-

green part to become fluid
ing may now be perfor
To do this the

being gently
begin to
edge

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عمارت

MUSIC.-CONTRAPUATIST'S note has been laid before the composer of the

harmony he criticises, who has kindly sent the following reply:-" Both the passages are correct, and agreeable to the ear. In both of them, the dissonances are passing notes. Reducing the first passage (the first complete bar of Happy Mind') to its elementary form, it consists of two chords, the tonic F, and the dominant c, which last is represented by its third E.

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an (Scremerston): position of integration; the latter mean. ring all parts; the former, therefore, means a destroying

e wholeness, a reduction to parts.-F. E. FLETCHER (Cheltenham): Such queries as his must in future be referred to the editor of the "Pathway."ATHOS (Newcastle): The answer to the snail query is 16 days. Perhaps the glowworm was an ignis faluus.-A FACTORY LAD (Wardle): His inquiry about the Normal-school will be answered. His derivation of mill shows ingenuity, but it is a Saxon word; see Johnson's Dictionary.-M. W. N. (Manchester): At the extinction of the Roman Empire, which, according to Gibbon, took place at the death of Theodosius, "Arcadius and Honorius ted Emperors of the East and West;" the eastern empire, comprisefectura Orientis et Illiryci, was allotted to Arcadius, and the mpire, comprising the Prefectura Galliarum et Italiæ, to

agreeable melody, two notes are introduced-the a, and a appogiatura or note of taste, above the e, and

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would naturally introduce as a connecting as to give roundness and smoothness to the s in connexion with the under part gives In the second passage, the F in the underwith G in the upper, is a note of suspension, et which would otherwise be produced by at by our correspondent. The passage in its

Lela

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ifully printed, super-royal 8vo.,

BIN ALMANACK; or, THE ABOLITIONIST Det complete work on the question of slavery hed. Everybody who has read "Uncle Tom's res of a copy of this book, which more than Irs. Stowe's thrilling narrative. This work is rge Cruikshank, Esq.; J. Gilbert, Esq.; W. Esq. ("Phiz"); and other eminent artists; and super-royal 8vo., replete with the most stirring Law; an Negroes; the Workings of the Fugitive Slave and Historical and Descriptive Accounts of been disposed of within three weeks. American Slavery. already is very large, 30,000 copies having ILLUSTRATED EXHIBITOR ALMANACK, Thirty splendid Engravings, 6d. POPULAR EDUCATOR ALMANACK, Notices and Essays on Education, 2d. TEMPERANCE ALMANACK, Tale by the Authoress of Uncle Tom, &c., M. PROTESTANT DISSENTERS' ALMANACK, with new Historical Notices, &c. 5d. Printed and Published by JOHN CASSELL, La Belle Sauvage Yard, Ludgate hill, London.-December 11, 1852.

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LESSONS IN GEOLOG Y.-No. XXI.
BY THOMAS W. JENKYN, D.D., F.G.S., &c.

CHAPTER II.

ON THE ACTION OF WATER ON THE EARTH'S CRUST.

SECTION VI.

ON THE AGENCY OF WATER IN ABRADING HARD ROCKS.

THE last lesson taught you the mechanical agency of running | turn, becomes abraded by a repetition of chemical infiltration
water in excavating soft and loose soils. You have now to turn and mechanical disturbance. As the process goes on, the bed
your attention to the combination of its mechanical and chemi- of the stream becomes deeper and deeper in the underlying
cal action in eroding and abrading hard rocks; that is, in rock.
gradually and imperceptibly wearing away the surface of hard
rocks, and forming, for its current, a bed or gorge which it has
excavated by its own power.

In an earlier lesson it was shown that water, by its chemical
agency, has the power to decompose and disintegrate some of
the hardest rocks. Your own observation must have informed
you that there is a constant tendency in all substances to be de-

The gradual abrasion of deep beds-such as may be called chasms or gorges-in some of the hardest and most compact rocks, by the incessant action of running water charged chemically with gases, and mechanically with gravel and pebbles, is one of the most interesting phenomena in geology. The business of this lesson is to furnish you with a few specimens of this abrading agency.

Fig. 49.

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An Ideal Bird's-eye View of the Country about the Falls of Niagara.

composed or disintegrated, to be removed by currents, to be
carried away to a lower level, and finally to be deposited in
some river, pool, lake, or the sea.

A running stream necessarily combines in its action the two
powers of water. By infiltration into the mass of a rock, it
tends to separate the particles of which it is composed. In
this process, it acts chemically on the cementing matter that
made the rock hard, and, by dissolving it, sets its particles at
liberty. Its mechanical power then dislodges these particles,
and forces them away from the surface on which it acts. When
these particles have been removed from the surface, the rock
presents to the running water a fresh surface, which, in its
.. VOL. II.

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In the volcanic districts of Auvergne, in Central France, there are many examples of valleys, across which streams of lava have, at some ancient period, flowed, and, on cooling, have formed a high embankment or dam, which has completely stopped the course of the river at the bottom. These lava embankments furnish the most clear instances of the abrading power of running water. The rivers that have been stopped, collected their waters, and then have cut out and cut downwards for themselves fresh passages, which now appear as large chasms in the lava, some of them from twenty to seventy feet in depth, and frequently of great breadth.

The materials on the surface of the sides of these valleys, 38

show that such new chasms or fresh beds of the river have not feet deep. Its water is beautiful sea-green, and its current is
been affected, as is sometimes the case, by the current of an full six miles an hour, For a few miles from the lake it is
ancient sea, or by the denuding wave of some debacle or almost on a level with its banks, which are so low on each side
deluge. The geological proof of this fact is that, a little higher that, if the waters were to rise eight or ten feet, many miles in
up in the valley, and at no great height above the present level | Canada on one side, and in the state of New York on the
of the river, there are, at the present day, many heaps or cones other, would be under water. In its course for about fifteen
of scoriæ, or cinders, out of which these melted lavas flowed. miles it varies in breadth, being sometimes one, sometimes
You can now reason' out this geological argument for yourself. two, three, and nearly four miles wide. Here it enters what
If this district had, at any time since the settlement of these are called the “Rapids," and falls about fifty feet for every
banks of lava across the valley, been either submerged under mile.
the sea, or had been subjected to the sweeping action of a At the end of the rapids, and at the very edge of the fall,
deluge, it is evident that all those light cones and loose heaps an island divides the river into two sheets of water, and, conse-
of cinders would have been carried away. Hence, it is quently, into two stupendous cataracts. One is called the
obvious that the present channel of the river excavated in the Horse-shoe Fall, and is on the Canadian side of the river, and
embankment has been effected by the abrading power of the the other is called the American Fall. The stream of the
river itself.

Horse-shoe Fall is six hundred yards, or eighteen hundred The neighbourhood of Etna furnishes another example of feet wide, and falls one hundred and fifty-eight feet perthis abrading power of water. At the base of Etna, westward, pendicularly. The American Fall is two hundred yards a current of lava has descended from near the summit of the wide, and one hundred and sixty-four feet perpendicularly, volcano to the distance of some six miles, and has crossed the To form any good conception of the abrading power of this valley of the Simeto, the largest river in Sicily. It has flowed river, you must detain your mind upon the enormous volume from one side of the valley to the other, and when it reached of its water, and upon the force of its accelerated velocity in the opposite side, it accumulated there as a rocky mass. This the rapids. The river immediately below Navy Island is lava Howed across the valley about the year 1600. It has nearly four miles wide, but just above the falls it is about every appearance of being one of the most modern eruptions three miles, and at the falls it is, in a moment, contracted into from Etna, for it has not been covered or crossed by any subse- three quarters of a mile. It has been mathematically calcuquent ejections or streams of lava.

lated that the weight of its volume of water, running at the Through this bed of lava, which is of considerable breadth, rate of six miles an hour, would be more than one hundred the Simeto has abraded and excavated a passage from fifty to million of tons. This, in one day, would give the mechanical several hundred feet wide, and, in some parts, from forty to action of a body more than two thousand millions of tons in fifty feet deep. This channel has been abraded in 250 years, weight.

This abrasion is the more remarkable, when you consider This amazing volume and tremendous weight of water is that the portion of lava excavated is in no part porous, but precipitated over a ledge of rock of hard limestone, which lies

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consists of a compact mass of hard blue rock, approaching the in strata almost horizontal, but dipping towards Lake Erie. consistency of basalt. The declivity in this part of the bed Below this stratum of limestone is a thick bed of shale, which of the Simeto does not give much velocity to the stream, but, is perpetually crumbling. The blasts of wind charged with in consequence of some part of the lava being more easily worn the spray that is constantly rising from the abyss under the away than another, there are two waterfalls in this gorge, each cataract, strike against this bed of shales, and incessantly disinof them about six feet in height. In this neighbourhood, the tegrate it. As this bed of soft shale crumbles away, chiefly chasm is about forty feet deep, and only fifty feet wide. In through the action of the gusts of spray, and partly through approaching the waterfalls, therefore, in the channel of the the expansive agency of frosts, the calcareous rocks above river, the visitor to the two cataracts is entirely shut out form an overhanging mass, which projects some forty or fifty from all view of the surrounding country.

feet over the whirlpool below, In proportion as these shales The most clear, and, perhaps, the most magnificent example wear away, the overhanging rock is left without support. The of the abrading power of rivers, is found in the celebrated consequence is, that, from time to time, immense masses fall Falls of Niagara, in North America.

headlong into the profound abyss below, with a sound the This river is one of the most stupendous in the world; though most terrific. Such a fall took place on the American side, its significance and glory in the river systems of the earth is in 1818, and on the Canadian, in 1828 ; and on both occasions much lost by its having different names in different parts of its the whole surrounding district was shaken as if by an earthcourse. From Montreal to the sea, it is called the St. Law- quake. rence; but from Lake Erie to Lake Ontario, it is called the The engraving in page 165, and fig. 49, is designed to give an Niagara. It also bears many other names.

ideal bird's-eye view of the district of Niagara. In this diagram, The first springs of this noble river are found amid the the chasm, or the river-bed, from the falls to the clitts at sources of the majestic Mississippi; but, under the name of Queenstown, is represented as being almost a straight line. Niagara, it flows from Lake Erie to Lake Ontario, a distance of This is not really and physically the case. The chasm is about thirty-two miles, in a course almost due south and north. represented straight, for the sake of giving a more distinct view After leaving Lake Ontario, it meets the tide four hundred of the stratification of the limestone and shales from Queensmiles from its mouth, where it is ninety miles wide, and town up to the falls. For the same purpose, the proportions finishes a course of three thousand miles in length.

of the heights also are designedly exaggerated. Lake Erie, from which the river flows, is three hundred A glance at the above diagram will show you that the abrad. and thirty feet, or more than a hundred yards higher than ing power of this river has scooped out for itself a bed or gorge Lake Ontario, into which it empties its enormous mass of seven miles in length, and about half a mile in breadth. The waters. When the river starts from Lake Erie, it appears, for depth of the river itself is more than a hundred yards, or fifty some distance, as a continuation of the lake, is about three fathoms. How deep the cataract has scooped into the bottom quarters of a mile wide, and from twenty-five to thirty of the pool below it it is impossible to calculate; but logs of

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