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distant from the angular point than the point assigned within constructed, the sum of the three angles is the same as in the the angle; in either of these cases the assumption made above original triangle; and moreover that of the angles of these two will have been allowed” (p. 28). To which the answer seems to triangles which are at a common point, that belonging to the be, that to know by what necessity attendant on the constitution new triangle is not greater than half that of the old, while another of the straight line, the several results here taken for granted of the angles of the new triangle is equal to their difference. will take place, is precisely the object which it was in question And if these operations be applied in like manner to the last conto attain. The apparent application of the proposed principle in structed triangle, a third triangle will be constructed having the the

20th Proposition of Euclid's Eleventh Book, is a mere error same relations to the second, and so on. Whence it follows, of Euclid's, and corrected by the Arabs, and subsequently by that the described process may be continued, till two of the angles Legendre and probably others, through a very simple alteration of the last-resulting triangle are together less than any magniin the construction. Euclid's straight lines will fail to meet, tude that shall have been assigned ; and consequently the third whenever his greatest angle exceeds half the angle cut off, by not or remaining angle may be made to approach, within any magless than a right angle, T'hus if the angles composing the solid nitude however small

it may be chosen to assign, to the sum angle were 700, 800, and 130°, neither by cutting off one of the of the three angles of the original or any of the intervening smaller angles nor the other, could Euclid's intended construc- triangles. tion take place.

All this is irrefragable; but not so the inference next taken 20. Professor Thomson. 'of Glasgow, proposes to take as an for established, which is that the third angle last mentioned Axiom, that "if a triangle be moved along a plane, so that its approaches within any magnitude however small it may be base may always be on the same straight line, its vertex describes chosen to assign, to the sum of two right angles. That it 2 straight line equal to that which is described by either extre- approaches it (that is, that the angle continually grows larger) is mity of the base."** In which there are two things demanded, certain; but that it approaches to it within any magnitude howwhere either would be enough. For if it could be established ever small

, is the point which, as in so many parallel instances, is ,

asing else taken for granted without sufficing proof. The weakness in the might be demonstrated without premising that the lines described actual case, is in the fact that the base or side opposite to the are equal; as has been done in kindred cases by Clavius and continually increasing angle, becomes itself of unlimited length. others. Or if it could be established that the distances between If the resulting triangles had been all on the same base, the the first and last situations of the travelling points respectively inference might perhaps have been conceded to be good. But it are equal, this would suffice for the author's own demonstration, is precisely because by the extension of the base to an unlimited without asking whether the vertex had been always in the join- magnitude the progress of the operation is removed from human ing straight line. But how the equality of these distances is to eyes, that the force of the inference is diluted and done away. be established, does not appear. One way of trying to proceed, Just as fast as the diminution of the two acute angles appears to would be to show, that if the line on which the base of the induce a necessity for the obtuse angle's approximating to the triangle travels (and of part of which the base is composed), sum of two right angles, does the increase of the length of the instead of a straight line were a circular arc, the vertex would sides hold forth an augmented probability that the angle may travel farther than the point in which the straight line from the after all evade increasing by the quantity required to make it vertex to the centre cuts the base, if on the convex side, and less attain to two right angles in the end. To argue that when the far if on the concave; which is easily done, by proving that if acute angles are nothing, or the lines coincide, the third angle not, the straight lines that ought to be the radii of the circle will make a straight line,- is substituting for what really happens, would not meet. And this would throw the responsibility on what by the construction is not to happen. The demonstration establishing, that the radius of a circle may be increased tilla is therefore finally, of the same strength as Franceschini's and portion of the circumference approaches within any assignable others that have been mentioned. There is evidence of a perdifference to a straight line of given length; in other words, that petual approach towards a given magnitude; but there is not there cannot be three points not in a straight line, through which evidence of the degree and rapidity of approach which are a circle may not be described. Which involves Euclid's necessary to insure arriving at it.

24. Another demonstration, or step towards a demonstration, 21. The demonstration presented by M. Legendre in the presented by the same author (See Note II. p. 279, 12ème édition), earlier editions of his “Eléments de Géoinétrie;" consisted in first consists in representing, that if any angle less than two right establishing that the three angles of a rectilinear triangle cannot angles is bisected, all perpendiculars to the bisecting straight be greater than two right angles (which may be passed over as line must meet the sides, because otherwise there would be a irrefragable and liable to no remark), and afterwards proceeding straight line shut up between the lines that make an angle, to show cause why they should not be less. But the evidence which is repugnant to the nature of the straight line.” On which offered on this latter point, depended on taking for granted that it is sufficient to observe, that the existence, cause, and origin of two straight lines (D E and B E in fig. 35 a in the Fourth Edition, this repugnance, are precisely what it was demanded to demonand probably in the subsequent editions as far as the Eighth strate. inclusive) meet when they nake with a third straight line (DB) 25. The next paragraph in the same page is directed to estabangles of which one (as E D B) is, or may be made to be, less than lishing the sort of postulate assumed in the last, viz. that a straight a right angle, and the other looks less than a right angle, but line cannot be shut up within an angle. The argument appears to without further proof.

be, that either of the straight lines which make an angle, being 22. In the Seventh Edition another attempt was made to show prolonged both ways, will divide the infinite plane in which it that the lines must meet; but what is advanced as the proof exists into equal parts, and any other straight line must do the involves the same fallacy as that of the Bolognese Professor.t

same; but a straight line that should be shut up [renfermée) 23. This was withdrawn in the Ninth Edition, and a new the sides in any direction however prolonged, would cut off niore

within the angle, without being able to escape from it by cutting demonstration offered in the Twelfth. The new one depended on one side and less on the other; therefore a straight line canupon taking in any triangle an angle that is not less I than any not be shut up within an angle. Whoever examines this closely, other in the triangle, and a second that is not greater (See 12ème will see that it would equally prove that two straight lives canédition, p. 20, and Plate); bisecting the side opposite to the second not be parallel to one another; for in that case it might equally angle, and drawing a straight line from the angular point to he urged, that if the one divides the infinite plane into two equal the point of bisection;, cutting off in this straight line and its pro- parts, the other must cut off more on one side and less on the longation a part from the angular point equal to the side opposite other. The whole is consequently a mal-reasoning, arising from to the first-mentioned angle (viz. that angle which is not less than overlooking Plato's observation (Šee Note to Prop. IV. of Book any other in the triangle), and in this side and its prolongation 1), that Guality of magnitude can only be predicated of things towards the same hand a part equal to double the straight line finite. between the angular point and the point of bisection formerly mentioned, and joining the extremities of the two parts thus cut

26. The nexu in order is the so-called analytical proof, which off. It is not difficult to show, that in the new triangle thus last professes to demonstrate that if two angles in one rectilinear

triangle are respectively equal to two in another, the remaining

angles are necessarily equal Iftwo angles of a triangle and the * " The first Six and the Eleventh and Twelfth Books of Euclid's Ele that individual triangle are determined, that is to say, they can

side between them are given, the rest of the sides and angles of ments; with Notes and Illustrations. By James Thomsom, LL.D. Professor of Mathematics in the University, Glasgow, 1834. Notes, p. 358."

severally be opis of one certain magnitude and no other. Hence, + Elém. de Géom. Par A. M. Legendre, 7ème édit. p. 280. Note II.

said the advanvers of this demonstration, the angle opposite to * Not less and not greater are substituted for the greatest and least of the the given side is a function of the two angles and the given side; original. The demonstration is plainly intended to be applicable to any

--their meaning by this term being, that a quantity is a functions triangle; but the terms in the original would not apply to an equilateral of other quantities, when on those other quantities being fixed triangle, nor to any kind of isosceles.

and determined in magnitude, the first quantity is necessarily

Axiom.

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fixed and determined in magnitude,* or is what Euclid in his beds in which are only about 3.4 per cent. of species identical with Book of Data would call given. “Let the right angle be repre- the present, are called Eocene, from nws, eeos, dawn, as if in this sented by unity or 1, and then the angles will all be numbers group we find the first indication or dawn of the existing species, somewhere between 0 and 2; and since the third angle is a func- since no recent or present species have been discovered in any of tion of the two other angles and the side between them, it will the secondary or the primary formations. follow that the side cannot enter as an element into the determination of the magnitude of the angle. And this, they said,

As the geological designations of these rocks are founded on because the side is heterogeneous with the other quantities which their respective proportions of fossils identical with the recent are numbers, and no equality can be compounded or made to fauna, you will perhaps find that the following summary exist between tliem.t

explanation of them will answer every purpose in your efforts to
learn the science,
1. The Pléistocene

( most recent, or containing most of recent LESSONS IN GEOLOGY.No. L.

2. The Pléiocene (very recent, or having a large number of

recent shells. By Thos, W. JENKYN, D.D., F.R.G.S., F.G.S., &c.

middling recent, or having a small propor3. The Méioceno

tion of recent shells. CHAPTER V.

somewhat recent, having some few indica4. The E'ocene {

tions of the present race of shells. ON THE CLASSIFICATION OF ROCKS.

These groups are ascertained partly by their lithological characSECTION IV.

ter, and partly by their palæontology, or their fossil contents.

ON THE TERTIARIBS.

& 1. THE LITHOLOGICAL CHARACTER OF THE TERTIARIES. The term “ Tertiaries," as applied to certain beds, has a reference

The lithological character of a bed means the kind of material, to the three grand divisions into which the fossiliferous rocks have been distributed by geologists. If you will consult the sandy, clayey, flinty, or limy ingredients of which the rock iš tabular view given in the commencement of this chapter, you

composed.

The upper group of the Tertiaries are called Pleistocene, and will find that, taken in an upward direction, all the rocks from By from the Trias to the Chalk are called SECONDARY; and that the Silurian to the Permian are called PRIMARY ; that all the are thus divided into minor formations.

I. TRE PLEISTOCENE. all the beds between the Chalk and the Recent, or what I have called Post Pleistocene are called TERTLARY.

1. The Boulder Formation, or Drift. The tertiary rocks are generally divided into three, or rather four 2. The Norwich Crag. distinct groups, called, as viewed downward, the Pleistocene, the 3. Cavern Deposits and Osseous Breccia. Pleiocene, the Meiocene, and the Eocene. These terms were

4. Sicilian Limestone. introduced and invented by Sir CHARLES LYELL. The reasons of this distribution are founded on the proportion which the fossil

I. THE BOULDER FORMATION, OR DRIFT. shells of each group bear to the species now living. All the recent rocks, called in our last lesson Post Pleistocene, might ing lesson as being found associated with freshwater strata and

The drift, or boulder formation, Las been described in a precede have been called Anthropozoic, that is, human-life rocks, but for marine beds, and as having been formed about the close of the the fact that their

lower division contains fossils of all the existing pleistocene period. The mineral ingredients of this formation species of shells,

without any remains or traces of the human race. exhibit every where a confused mixture of the ruins of adjacent Sir Charles Lyell takes the fossils of this division

of recent rocks lands, and an immense

number of stones, some angular and rugged, as his standard in grouping the other beds downward to the others rounded and smoothed, and brought to their present posichalk. All the different beds downward to the chalk, contain tion from

very remote districts, by the agency of icebergs. In different proportions of the shells called present, modern, or the Eastern counties of England, this formation supplies speci

, , the feminine kaivn kainee. It has been the arbitrary, custom of far south as to Muswell Hill, near London, and no trace of it is

mens of almost every known rock. It extends from Scotland as English scholars to write the Greek at as a diphthong, thus æ, and found farther south. The best place to study it in England, is in the x as c. Hence the uncouth word cane, now generally written the cliffs of the Norfolk coast, where it presents a section from 50 cene and pronounced seen. Hence, the above names are pro- to 70 feet high, and about 20 miles in length. In that section nounced as if written Ply'-sto-seen, Ply'-o-seen, My'-o-seen, it consists of clay, loam, and sand, partly stratified and partly unE-0-scen.

stratified. It contains pebbles and boulders; of porphyry, greenThe beds which contain the greatest abundance of living or stone, lias and chalk. These are found everywhere interspersed, recent shells., i.e. from 90 to 95 per cent., are called Pleistocene, but especially in the Til. from a LOTOS, pleistos, most. The beds which contained some smaller proportion than this, but more than the inferior beds, are this formation in North America, and in the northern parts of

Your attention has already been directed to the vast extent of called Pléiocene, from a śwwv, pleión, inore. The next underlying Russia and Germany, and also to the Alps as another centre from beds, as they contain only from 35 to 50 per cent., are called which these erratic blocks have been carried by icebergs. You Méiocene, from užius, meión, fewer or less. "The lowest of these find the same to be the case in your own country, as instanced in

the mountains of Galloway, Cumberland and North Wales. "toute quantité formée d'une manière quelconque d'une autre

Though the drift is, comparatively, a most recent formation, quantité."-Lagrange, Théorie des Fonctions Analytiques.

you are not to expect to find it always resting on some other " Il faut donc que l'angle o soit entièrement déterminé, lorsqu'on con. tertiary strata. In many places, and especially in Scotland, it is nait les angles A et B, avec le côté p; car, si plusieurs angles c pouvaient found to rest immediately on some of the older rocks, and is correspondre aux trois données A, B, p, il y aurait autant de triangles differents qui auraient un côté égal adjacent à deux angles égaux, ee qui est ime covered by stratified beds of sand and clay which are usually possible: donc l'angle c doit être une fonction déterminée des trois quantités without any fossila. Such a position is represented by the A, B, P; ce que j'exprime ainsi, o=$:(A, B, p)."

diagram, fig. 1, page 263, where a represents the ancient rock, and "Soit l'angle droit égal à l'unité, alors les angles A, B, C, seront des nom. bres compris entre 0 et 2 ; et puisque c=0: (A, B, P), je dis que la ligne pd, c, 6, various beds of the tertiaries. ne doit point entrer dans la fonction o. 'En effet, on a vu que c doit être entièrement déterminé par les seules données A, B, P, sans autre angle ni ligne quelconque, mais la ligne p est hétérogène avec les nombres A, B, 0; On each side of the river Yare, within five miles of the city of et son avait une équation quelconque entre A, B, C, P, on en pourrait tirer Norwich, are seen beds of sand, loam and gravel, which are called

These beds abound with qui est absurde : donc p ne peut entrer dans la fonction 0, et on a simple by the country people CRAG, or gravel. ment c=0: (A, B).”Legendre, Fléin. de Géom. 12ème édit, Notes. p. the shells of animals, narine, freshwater, and land. The strata The entire passage is inserted-at the end of these notes in English, that the sea near the mouth of a large river. This formation is found

have every appearance of having accumulated at the bottom of our st...ents may be able to judge for themselves of the merits of this con

in patches of different thickness, and covered with a dense mass

II. THE NORWICH CRAG.

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of stratified flinty gravel, and resting on the chalk. In the sea bones there. The preservation of such bones is due to the slow cliffa, near Thorpe and Southwold, Suffolk, this sea and river but constant supply of stalactite matter brought into the caverns formation is exposed in good and clear sections, where it consists by water infiltrating from the roof. of sand, shingle, loam, and laminated clay. Some of the strata Cavern breccias are found in every part of the world, but at appear to have been deposited in tranquil waters.

San Ciro, in Sicily, there is one of great interest. It is about 20 feet high, 10 wide, and 180 above the sea. Within it there is an ancient sea-beach formed of pebbles of different rocks brought thither from very distant places. Broken corals and shells mingle with the pebbles. Under a mass of breccia were found an immense quantity of bones of the mammoth, &c., in a dark brown calcareous marl, and many of the bones were worn as if rounded by the action of the waves. This bed of breccia is about 20 feet thick, and under it is a bed of sand filled with sea shells of recent species,

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IV. SICILIAN LIXESTONE.

XII. CAVERN DEPOSITS AND OSSEOUS OR BOXY

CONCRETIONS,

sea,

In Sicily the Pleistocene tertiaries enter largely into the structure of rocks, covering nearly one half of the island, and in the

centre forming hills which rise 2,000 feet above the level of the When rounded pebbles and gravel are cemented together into &

The structure and arrangement of these beds are best hard stone, the mass is called a conglomerate, and sometimes, developed at Girgenti

, Syracuse, and Castrogiovanni.

The Sicilian beds consist of two divisions. plum-pudding stone; but when such a cemented mass is composed of angular and unworn fragments of rock and other materials, it

The upper division is calcareous or limy, and consists of a is called, from the Italian, Breccia.

yellowish white stone in some places, and in others of a rock In mountainous districts, many fissures are found, into which nearly as compact as marble. The beds are usually regular and animals seem to have fallen from time to time, or into which they horizontal, and their thickness are from 700 to 800

feet. have been washed by floods. These animal remains are frequently

The lower division is clayey, or argillaceous, and pass downfound covered with alluvial matter and with fragments of rocks wards into a sandstone, and conglomerates : below which there which have been detached by frost. The whole mass is then are again clay and blue marle, abounding in perfect shells

and

corals, formed, by stalactite infiltration, into what is called a bony or osgeous breccia.

In the south plains of Catania these pleistocene beds are interLimestone hills often abound with a series of caverns with low while the rock was forming at the bottom of the sea, and while

, and narrow paguages from one suite to another, which hold a the clay, sand, and yellow limestone were in the course of being tortuous course through the interior of the mountain. Caverns and passages seem to have served, at some early period, deposited. All these Sicilian rocks belong probably to the same as the subterranean channels of springs and rivers. In the ter- period as the Norwich crag.

II. THE PLEIOCENE.

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1. The Suffolk Crag.
2. The Subapennine Beds.

ASTKAST

I. THE SUFFOLK CRAG.

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The Pleiocepe rocks are confined chiefly to the eastern parts of the county of Suffolk, where these beds like those of a later class in Norfolk, are called crag. This rock is a mass of shelly sand, which is much used in agriculture. Tbe shells imbedded in it, indicate that the bed was formed in a sea of moderate depth, in most plaues from 15 to 25 fathoms, but in some parts deeper, and at the distance of about 40 or 50 miles from any land,

The natural group of the Suffolk Crag series is divided hy Mr. Charlesworth into three subdivisions, which, in the downward order, are thus designated.

1. THE MAMMALIFEROUS CRAG; which is a sandy loan and clay formed by sea and river water, and charged with shelly detritus. It occurs about Southwold in Suffolk, and Cromer in Norfolk. It contains the teeth and bones of several extinct mammalia, or animals that suckle their

young. 2. THE RED CRAG; which is so called from its deep ferruginous or irony colour. It consists principally of quartzose sand and comminuted shells and corals, and is about 40 feet thick.

3. THE CÓRALLINE CRAG; which is a series of calcareous and marly strata of loose white sands, layers of shells and corals, and concretionary bands of stone. It is of very limited extent, about 20 miles in length, and three or four in breadth, covering a district in Suffolk between the rivers Alde and Stour. At Sudbourn, near Orford, in this county, there is a large quarry in this

formation furnishing a soft building stone. In some places, the Wat

softer mass is divided into thin flagg of hard limestone, presunting fossil corals in the upright position which they assumed in their growth.

Where the red and the coralline crags are met together in the game district, the red always lies uppermost, and both lie op tibe London clay. In some sections, the coralline bed seems to bave

suffered denudation before the red crag had been deposited on it. tiary period, these channels had become and remained open for The red crig is distinguisbed by its deep ochreous or yellow tho Lotos and shelters of animals which perished and left their pr than Shy its whith golo-ured sands.

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II. THE SUBAPENNINE BEDS.

1. THE UPPER EOCERE,

stone.

II. TIIE HIDDLE EOCEYE.

I!). THE LOWER EOCEVE.

I. THE FALUNS OF TOTRAINE.

The Alpennines, composed chiefly of secondary limestone, are a 1. Upper freshwater limestone, marls and siliceous mill. chain of hils which commence at the base of the Ligurian Alps and extend through the whole lengtb of Italy. At the foot of these 2. Upper marine sands or Fontainebleaa sandstone. mountains and on each side of them, is found a series of tertiary strata which forms a line of low hills between the central ridge of 1. Lower freshwater limestone and marl, or the gypseous mountains and the Adriátic on the east side, and the Mediterra

series. nean on the west.

2. Sandstones and sand with marine shells. The strata of these low bubapennine hills consist generally of

3. Limestone with marine shells, or Calcaire grossier. light-brown or blue marl, covered by a yellow calcareous sand

4. Hard, flinty, fresh water limestone, or Calcaire siliceaux, and gravel, imbedding fossil shells. The marl is very aluminous, containing much calcareous matter and scales of mica. Near Parma it attains a height of about 2,000 feet, abounding in marine 1. Lower sands with marine shelly beds. shells. Near Sienna, the yellow sand conglomerate rests imme- 2. De. with lignite and plastic clay. diately on the Apennine limestone, and at St. Vignone (pro- 1. THE UPPER EOCENE is represented in the upper marine nounced Vinion) it passes into a calcareous sandstone, As this beds of Paris, the Fontainebleau sandstone and millstone, the yellow sand formation is superimposed upon the marl, it repre- Kleyn Spawen beds, the Berlin tile clay, the tertiary strata about sents the deltas of rivers and torrents which gained upon the bed Mayence, and the freshwater formations in Auvergne. of the sea where the blue marl had been previously deposited. 1. The freshwater marls and limestones of Paris seem to have

Geologists now acknowledge that all the subapennine tertiaries been formed in marshes and shallow lakes. Some of the siliceous do not belong to the same period. The beds indicate three dis- rocks of this formation are used for millstones. tinct geological eras.

2. The upper marine sands consist of marls, micaceous and 1. The beds of Piedmont, e.g. at Superga, are Meiscene.

2. The beds of North Italy, Tuscany, and the Seven Hills of quartzose sand, with beds of sandstone abounding in marine Rome, are Pleiocene.

The Upper Eocene is not found in England. 3. The Tufaceous formations about Naples, Ischia, &c., are 11. THE MIDDLE EOCENE is represented by the Paris gypsum, Pleistocene, and Post Pleistocene.

the beds of Headon Hill in the Isle of Wight, the Barton beds,

and the Bagshot and Bracklesham sands. III. THE MEIOCENE.

Near Paris we find, below the upper marine sends, a series of

white and green marls, with beds : t gypsum lying under them, 1. The Faluns of Touraine, 2, Part of Bourdeaux.

which are best developed at Montmartre, where its fossils were

first discovered by CUTIER The gypsum is quarried for the 3. Part of the Molasse of Switzerland,

manufacture of the plaster of Paris.

In England, the Middle Eocene is developed in various

instances, In French Brittany, near Dinan and Rennes, and also in the

1. In Headon Hill, in the Isle of Wight, we find beds of marl, provinces bordering on the river Loire, there is a tertiary forma clas, sand, and a friáble limestone containing freshwater shells. tion called by the peasantry Faluns (faloons). It consists of shelly These beds are seen in the sea cliffs, where some of the strata consand and marl, and is used for agricultural purposes. Some of the shells and corals are entire, some are rolled, and others are in tain a few marine and estuary shella. comminuted fragments. In some places, &s at Doué, near Saumur,

2. In the cliffs of Barton, the pure white sand without fossile, these sands and marls form a soft building stone, which is com

on which the freshwater series of Headon Hill rested, is found to posed of broken shells united by a calcareous cement, and which repose on a marine deposit, in which 209 species of shells have looks much like a mass of the coralline (rag in Suffolk,

been found. This is the newest purely marine bed of the Eocene

series known in England. This formation exists in scattered patches of slight thickness, and very rarely exceeding 50 teet in depth. They are frequently about Bagshot and in the New Forest. They may be divided into

3. The Bagshot sande consist chiefly of silicevils sand found found tų rest on a great variety of older rocks, such as gneiss and three beds, the upper and lower being of light yellow sands, and clay slate. In other districts, as between the Seine and the Loire, the middle of dark green sands and brown clays, al' reposing on they repose upon the upper freshwater limestone of the Parisian

the London clay. tertiaries. At some points south of Tours, the shells are stained a ferruginous colour, like those of the red crag in Suffolk.

4. At Bracklesham near Chichester, there is a bay, bounded by The fossil shells indicate that these Faluns were formed partly

a low cliff of blue clay and green sand, full of fossil shells and

teeth, on the shore itself at the level of low water, and partly at very moderate depths, not exceeding ten fathoms below that level.

The lower Begshot sands have supplied the boulders of sandstones which are frequently found in some of the chalk valleys, and which are called Sarsden stones, and Druid sandstone, as may be seen at Stonehenge in Wiltshire, and Kitt Kotty near Maid

stone in Kent. Immense deposits of tertiary rocks are found in the country which lies between the Pyrenees and the Gironde river. Seven Sablés (sab-lé) of the Paris basin, the mottled and plastic clays

III. THE LOWER EOCENE consists of the London clay, the hundred species of shells have been found in these beds, and they of Hampshire and London, and the nummulites of the Alps. all indicate that this division of the Meiocene strata is older than

In the Paris basin, just below the Calcaire grossier, are extenthe Faluns of Touraine.

sive deposits of sand, having in the upper portion some marine beds called "Lits coquilliers," in which 200 species of shells have

been found. At the very base of the tertiary system in France, In Savoy we find, at the northern base of the great chain of are beds of sands and plaetic ciay abounding with fossil oysters. the Alps, and throughout the lower country of Switzerland, a In the lower clays and sands layers of lignite are found. soft green sandstone, which is probably one of the oldest Meiocene 1. The London Clay consists of a tenacious brown and bluisha groups hitherto discovered. It is associated with marls and con- gray clay, with layers of concretions called Septaria, which are glomerates and is called "molasse," derived from "mol," soft, as smployed in manufacturing Roman cement. The best places to the stone is easily cut in the quarry. It is of very great thickness, study this bed are Highgate near London, the Isle of Sheppoy and might perhaps be divided into several formations.

in Kent, and Bognor in Sussex. No rocks of the Meiocene period are found in England.

2. Mottled or Plastic Clays are accumulations of sand, pebbles,

and mottled clays. They are well developed in some of the railIV. THE EOCENE.

way cuttings about Reading, in Berkshire ; in different parts of

Hampshire; and especially about Blackheath and Woolvich. In The Eocene group of rocks is divided by Sir Charles Lyell into many places it appears to be a mixture accumulated by the comthree subdivisions, which he calls the Upper, the Middle, and the bined action of river and ses-water. At Poole, in Dorsetshire, Lower Kocene.

this clay is used for pottery, and hence the term “ plastic clay."

II, PART OF THE BOURDEAUX BEDS.

III. THE MOLASSE OF SWITZERLAND.

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sac. S

3. The Nummulite of the Alps and Pyrenees. This is a cal- NOTES AND REFERENCES.--a. Taire entendre raison au petit careous rock, consisting often of a compact crystalline limestone, B., induce little B. to listen to reason ; L. S. 96, R. 4. ---b.il full of nummulites or shells of the class Foraminifera, or ex- s'engagea une dispute, an altercation commencer; the verb is unitremely diminutive forms of shelly animals. As these fossils are

As these fossils are personal.--c. from se mettre ; L. S. 68, R. 3, also part ii., p. 96. very much like pieces of coin, and as nummus is the Latin for --d. remit, delivered; from remettre ; L. part ii., p. 102.--- L. coin, and nummulus, is little coin, this rock is called Nummulite. S. 43, R. 6.--f. fit coudre, had it sewed , L. S. 31, R. 3.-9. In the Alps this rock is of great thickness. In many parts of causa, talked, spoke.-k from falloir ; L. part ii., p. 92.-i. on Europe, Asia, and Africa, this group forms a very large part of se remit en marche, the march was resumed L. S. 34, R. 1, 2.the Tertiary formations. It is found in Algeria and Morocco; in j. the verb is unipersonal. —-k. from atteindre; L. part ii., p. 78. the Carpathian Mountains ; in the districts between Egypt and -. qu'il

, let it.-m. from suffire ; L. part ii., p. 106.—n. s'il Asia Minor; and between Persia and India.

restait, if there remained; the verb is unipersonal; L. S. 84, R. 4.-0. L. S. 77, R. 2.-p. L. S. 25, R. 2.-9. faire sauter, blow

ap.--. from produire; L. part ü., p. 100.-s. la retenait, supFRENCH READING S.-No. III.

ported it.
LE SAPEUR DE DIX ANS.

SECTION VI.
Le pauvre marchand voulut faire entendre a raison1 au

ANSWERS TO CORRESPONDENTS. petit Bilboquet, mais il était entêté comme un cheval aveu

GEORGE ISAAC E. (Nottingham): The Italian language has no nasal gle, et il s'engageab une dispute qui attira bientôt quelques sounds, and each vowel keeps its alphabetical sound irrespective of any soldats. Ils entrèrent pour s'informer du motif de la que consonant that may follow; e. s, in the words tempo, time; sento. I feel relle, et ils trouvèrent l'idée du tambour si drôle,» qu'ils mento, chin, the consonants m and n have no influence whatever on the obligèrent le pauvre Juif à lui céder sa barbe,4 et l'un tion of each voivel preceding them. The combination gn, pronounced as in d'eux, Gascon et perruquier du régiment, tira des rasoirs de French, is the only exception, and approaches a nasal sound. This constisa poche, se mitc à raser le malheureux marchands et a great extent a nasal language, and Italian a language spoken from the remita solennellement la toute à Bilboquet qui l'emportae chest. A great many examples in the first ten lessons, exclusively devoted. en triomphe.

En arrivant au régiment, il la fitf coudre have clearly illustrated this. The best Italian translation of the Bible, for par le tailleur sur un morceau de peau d'un tambour crevé,7 Protestant readers, is br Giovanni Diodati. The “Society for Promoting et sans rien dire de son dessein, il la mit au fond de son

Christian Knowledge,"67, Lincoln's-inn-fields, and the “ British and Foreign

Bible Society," Earl-street, New Bridge-street, Blackfriars, have both pubOn en causas pendant quelques jours, mais il falluth lished this translation. The price varies from 3s. 8d., 4s. 8d., &c., according to bientôt penser à autre chose. On se remiten i marche, et on ne the binding, and it may be had at the above-stated premises in Lincoln's-inn.

Fields, or at Bagster's, Paternoster-row. With regard to the Italian pensait plus au petit Bilboquet, quand on arriva à Moscou.

Dictionary, we must refer you to former remarks, and only beg to repeat Alors il arriva i d'affreux malheurs, le froid et la dévas- that the subject will be duls considered. tation privèrent l'armée française de toutes ses ressources, 19 Ball question; neither they nor she have 'mastered it yet. She is very

ANNA PRINGLE (Ferry Hill): she must try and beat the boys in the Four la famine l'atteignit,” et bientôt il fallut se retirer à travers right about fractional questions

and solutions ; we are proud of her corresun pays désert et des neiges sans fin. Je ne veux pas pondence.-E. PHILLIPS (Machen): We are sorry that we can't give our

corresyondent the information he requires. vous faire un tableau de cet horrible désastre ; c'est une

T. G. L: The result will be most conveniently illustrated by regarding chose trop vaste et trop épouvantable 12 à la fois, pour que the solution as hydrochlorate of protoxide of tin: to which solution nitric je vous en parle dans cette histoire : qu'il vous suffise m de protoxide of tin, and converts

it into peroxide. One portion of this peroxide savoir que chacun s'en retournait comme il pouvait,13 et is precipitated, leaving an excess of hydrochloric acid to combine with the que c'est à peine s'il n restait quelques régiments réunis en

rest. Thus the hydrochlorate of peroxide of tin results.

4. C. HILLARY: Probably the inetal was not in the state of fine powder, corps d'armée et obéissanto aux généraux. Celui de Bil- or the acid employed was not sufficiently strong. boquet était de ce nombrc. Il était de l'arrière-garde,l4 qui E. WILLIAMS: The result of such distillation would not be simply one empêchait des milliers de Cosaques, qui suivaient la retraite chemical product, but many very complex products, whose investigation

would belong to the higher departments of organic chemistry. de l'armée, 15 de massacrer les malheureux soldats isolés.

D. B. Ç. (Hartlepool): We do not answer some questions for fear of giving Un jour, ils venaient de franchir une petite rivière, et, offence to some readers, especially when they refer to religious worship. pour retarder la poursuite des ennemis, on avait essayé de Walk): The ch in archbishop is pronounced like ch in church.-MATHETES faire sauter 9 deux arches d'un pont de bois qu'on venait de The Greek upsilon is generally replaced by y in English ; as in ouv, with; traverser ;

16 mais les tonneaux de poudre avaient été posés astronomical day begins at the noon of one day, and terminates at the noon si precipitamment,17 que l'explosion ne produisit' que peu of the next day. The civil day varies in different nations; with ourselves d'effet : les arches furent cependant démantibulées, mais it begins at midnight of one day, and terminates at midnight of the next day. toute la charpente appuyait encore sur une grosse poutre STUDENT will get solutions of his questions in any treatise on Trigonometry: qui las retenait,18 et qui, si les ennemis fussent arrivés, eût --Don Quijote (Grahamston): We don't know any Spanish Dictionary

about 88. or 10s. that we can recominend.-B. H. (Bristol): See page 79, bientôt permis de reconstruire le pont.19

vol. iii. P. E., where the rule is that things without life are neuter. Now COLLOQUIAL EXERCISE.

heurt and land apart from the body are without life, and therefore strictly

But by poetic gender, as it is called, sex may be attributed to these 1. Le marchand chercha-t-il à | 11. Que fut-elle bientôt obligée nouns: in that case, we should call the heart feminine, and the hand mascu-le dissuader?

de faire ?

line, that is, if we were writing poetry.--HOPEFUL: Very well, go on.2. Pourquoi ne put-il lui faire 12. Pourquoi l'auteur ne veut-il Sochus (Liverpool) should have had an angwer it his address had been entendre raison ?

point faire le tableau de cet YOUNG WHITEBRBAD wishes to know the proportion in which liquor 3. Comment les soldats trou- horrible désastre?

potassæ must be added to sugаr of lead in order to produce the potash solu

tion of oxide of lead so useful as a test for sulphur, vèrent-ils l'idée du tambour? 13. Que suffit-il de savoir ?

A slight amount of consideration will prove to our correspondent that the 4. Que firent-ils ?

14. Où se trouvait le régiment proportion will altogether depend on the strength of the liquor potassæ and 5. Que fit le perruquier du ré- de Bilboquet?

of the lead solution. The best plan of procedure consists in disregarding giment ? 15. Que faisaient les Cosaques ? solution until the desired result is accomplished. Thus, having taken some

weighed or measured proportions, and adding liquor potassa to the lead 6. Le tambour parut-il content 16. Qu'avait-on essayé de faire solution of acetate of lead (sugar of lead), or still better solution of trisacetate de sa prise?

après avoir passé la rivière ? of lead (Goulard's extract), add to it by small quantities at a time liquor 7. Que fit-il de cette barbe en 17. Pourquoi l'explosion n'a potassa until all the oxide of lead is precipitated. Then continue to add

more until nearly, but not quite, all this precipitate is redissolved. By thus arrivant ?

yait-elle pas eu beaucoup leaving a little oxide of lead, the operator is assured that liquor potassæ has 8. Où la plaça-t-il ensuite ? d'effect? 9. Parla-t-on longtemps de 18. Pourquoi la charpente du

G. H. BALDING (Hastings) wishes to know how to make crucibles for

chemical experiments. He is not sufficiently precise. cette aventure ?

pont ne tombait-elle pas ? crucibles ? and what kind of experiments? The crucible adapted for ons 20. Qu'arriva-t-il à l'armée fran- 19. Qu'est-ce que les ennemis use is totaliy unfitted for others. The chemist employs crucibles of clayçaise après après son entrée à auraient pu faire, s'ils étaient ware, German porcelain, blacklead-ware, iron, silver, platinum, and, oc

casionally, gold; but he does not prepare those crucibles himself; they ars Moscou?

arrivés ?

the manufacture of various trades.

neuter.

given.

not been added in excess.

What sort or

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