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ON PLUTONIC CHANGES IN THE STRATIFIED SURFACE OF THE EARTH.

You have become acquainted with three causes which have are on a higher level than the crust A, from which the materials contributed to the production of the earth's crust. These are- were originally worn down ; or of which a has been denuded. 1, the first hardening of the surface by cooling ; 2, the action Since the laws of Hydrostatics would prevent water from deof subterranean heat in throwing up eruptive rocks through positing matter at this high level, the elevation of the beds fissures to the surface, and also consolidating “nether-formed” | must be ascribed to the action of the heat from below. rocks below the crust; and 3, the action of water in dissolving,

This elevation would take place gradually and tranquilly, wearing away, or disintegrating, portions of upper rocks, and in consequence of the slow expansion of the crust A B. This carrying down the sand, or detritus, to deposit it at a lower elevating expansion of the crust is not represented in fig. 5, level.

which is only designed to show the action of heat in altering Upon an examination of sedimentary rocks, there are two rocks. inferences which you cannot avoid making. The first is, that

Before the sedimentary rocks had been deposited, the crust the rock which has been worn or abraded by the water, must | heat very slowly, and the consequence would be that the tem

A B parted with its heat freely : but deposits of clay conduct have been older than the rock formed by disposition. The perature of the stratum, below such beds of clay, would increase second is, that the rocks thus worn by running water must, at to a higher degree. The increase of heat in the stratum below, the time of disintegration, have been at a higher level than the would enlarge its bulk by expansion ; which, in its turn, would

! place where they are deposited. To this second inference,

elevate the newly-formed deposits, above their former level; there is one exception. Water, hot or boiling, has a greater a large island or small continent.

80 that what was once the bottom of the sea may become

This you will moro disintegrating power to act upon rocks, chemically, than when easily understand, if you imagine that, previous to the elevait is cold. When the earth's crust, therefore, had only just tion of PD G, a sea existed on the line PG. become cool enough to allow water to exist upon it, in a fluid

It is not the science of geology only which asserts and proves state, and not in one of vapour, the heated, boiling, agitated that such elevations have taken place in very remote ages; for waters must have worn away the granite at their bottom very our day. The changes of level which take place along sea

our own observation can demonstrate that they take place in deeply and extensively. These abraded materials which the coasts, are ascribed, by the common people, to the sea receding; waters held in solution or suspension, they would deposit, but geologists can show that the change is the result of the either in deeper hollows, or along surfaces, that were of a lower earth rising. temperature.

Even so late as the year 1822, in the neighbourhood of Val. There are some phenomena developod in the condition of South America, was raised three or four feet above its usua.

paraiso, the whole coast of Chili, on the western side of some of these sedimentary rocks that will greatly puzzle a level along a line of more than a hundred miles in length. young inquirer when he meets them for the first time. They There could be no doubt of this elevation, for, after a tremendous are sometimes on a higher level than the rock from which their earthquake, an old ship that lay as a wreck at some distance sands or clays have been derived. In other cases, they are so

in the water, could, after Nov. 20th of that year, be safely altered in general aspect and mineral character, that he would of whose existence the inhabitants of the city knew nothing, was

visited dryshod : and an extensive bed of oysters and mussels, hardly recognise them as stratified deposits. In other places, now exposed, which with the dead fish contaminated the air with they are so disjointed, dislocated, and separated from the their bad odour. At this moment, the coast of Sweden, from series, of which they formerly constituted a continuous part,

Frederickshall to Abo in Finland, is gradually, but visibly, that their stratification appears almost reversed.

rising at the rate of about three feet in every hundred years ;

but the rate varies in different parts of the coast. This elevaAll these changes are owing to the action and force of sub- tion is proved by the fact, not only that shores are now dry terranean heat, as will be shown in the following illustrations, which used to be covered at low water, but, that the shells of

fish which now live in the Baltic abound in the soil which is about four feet higher than the water, and that at the distance of about seventy miles from the present margin of the sea. It is also a fact that barnacles, shellfish which attach themselves only to rocks or walls

washed by the sea, are now found fixed on high E

parts of the cliffs ; which proves that these cliffs with their barnacles were once at a level which could be washed by the sea. You therefore see, that wherever the sea is receding, it is occasioned by the earth rising, and that this rising is caused by the expansive power of heat

below. The elevation and alteration of sedimentary portions of the earth's crust

While heat is, by expansion, affecting and by subterranean heat.

elevating rocks that are remote from it, it is

acting with greater intensity upon the rocks In fig. 6, is represented a large portion of the earth’s crust, which lie nearest to it. It is consequently found, that, when covered by sedimentary rocks, which have been deposited by

the lower beds of the sedi:nen tary rocks' lie near enough to the action of water. A B represents the original crust now

the fusing power of heat, they are the most altered by it, both in resting on the nether-formed rock c, to which reference was

appearance and even in mineral, or lithological character. made in Lesson III. De are sedimentary beds, deposited on De, fig. 5.

This is represented above in the darkened portion of the beds the crust in its primitive state along the line F B. The deposits This operation of subterranean heat in altering sedimentary VOL. I.

16

Fig. 6.

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B

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rocks is not, in this lesson, to be mistaken for the action of thick beds of stratified gneiss, which is only granite worn away volcanic intrusions, whether of granite, of basalt, or of trap, to by water, to be deposited on a bottom of granite, you can which future lessons will refer. Both actions are analogous imagine that the subterranean heat might acquire such intento each other : but this lesson refers to very early changes sity as to melt the granite crust under the gneiss afresh. This which have taken place in the earth's crust, and which might fresh fusion would rise to reach the lower beds of the overlyhave been expected from the influence of intense melted mat- ing gneiss, and to penetrate them so thoroughly, as almost to ter, and from the effort of disengaged gases struggling to make destroy completely, all trace of the original lines of their stratitheir way through the porous rocks that overlay them. fication, and make them to appear as if they had never been

The alteration which intense heat produces in a sedimentary under the action of water. rock, will always be according to the nature of the deposit of Keep in mind that these changes in the character of altered which it is formed. Shale, a laminated clay, will become so rocks is not produced by heat alone. Volcanic action, in what indurated and compact as almost to lose its slaty peculiarity; may be called recent and modern epochs of geological time, Argillaceous, or earthy limestone, will become granular and assists us in studying the character of Plutonic action in more crystalline, like the white marble of the statuary. The clays remote ages. It is well known that volcanoes send forth imof the coal formations will appear like finty or jaspery slate. mense volumes of heated gases, which disengage themselves Coal is turned into anthracite, or stone-coal ; and anthracite from melted matter, and struggle to make their way from the into coke. Chalk becomes crystallised marble; which has enormous pressure which overlies them. They maintain this been verified by a chemist who applied intense heat to chalk, effort for weeks, months, and years. When, therefore, fused sealed in a gun-barrel. Thus, then, it is seen that the clay- granite or porphyry is burning, boiling, and heaving under great slate used in roofing houses, is nothing but clay that has been pressure, and containing powerful gases which cannot escape, subjected to strong heat under great pressure.

these gases will act upon the crust above; and, when they are Though these kinds of alteration are remarkable, still greater near porous rocks, they will pass through them with great ones may have been produced in proportion to the greater in- facility, and, in passing, greatly modify them. tensity of the fusing heat; or according to the length of time It is true that we can study these phenomena only as they in which the action of heat continued. There are, for instance, are observed on the surface of the earth ; but it is clear that as in the extreme south of Norway, sedimentary rocks penetrated gaseous fluids have altered the upper surface of the rocks, and by a large mass of granite, which must have protruded itself in as these fluids could only come from subterranean sources, they a state of fusion. All

Fig. 7.

must have made their about the mass of

way through the entire granite, the sedimen

crust, from the deep tary beds are altered

reservoirs below into to the distance, from o

the open air. the once melted mat

Other alterations of ter, of from fifty to

strata will be more fully four hundred yards.

considered when we Before this protrusion

D come to the subject of took place, the shale

metamorphic rocks, or the schist consisted

E

and to the influence of of green and chocolate- A

volcanic action in the coloured layers of sedi.

B protrusion of trap and ments; but the fused

basalt. The Plutonic granite has changed

changes, just alluded these into ribboned

to, are mentioned now, jasper, like those which

only to illustrate one of are found in the pebbles

the operations of heat at Aberystwith, in

on the early crust of South Wales,-speci

H

the earth. mens in which each The dislocation of sedimentary strata by eruptive rocks.

In fig. 6, while the stripe faithfully repre

lower portions of the sents the original lines in which their various clays were sedimentary beds D E are represented, by darkened lines, as deposited. The limestone of the neighbourhood, which was having been altered either by heat or by gases, the altered strata originally of an earthy texture, and of blue colour, as it is still retain their original relation to the beds that have not been stils found at a distance from the granite, is become white altered. There are, however, innumerable instances in which granular marble. It is also remarkable that both the slate stratified beds, whether altered or not, have been completely disand the limestone of that rock contain garnets, and ores of turbed and dislocated, as represented in fig. 7. A thousand iniron, copper, lead, and silver.

stances are found, in which the strata have

been broken through In Cornwall, also, the fused granite has protruded veins into and tilted up, so that what was deposited horizontally appears a rock, which the Cornish miners call "killas," a coarse argilla- now with their lines of stratification highly inclined ; sometimes, ceous or earthy schist or slate,-a rock which has been altered almost perpendicular ; at other times perfectly vertical; and, in by the heat of the fused matter, into hornblende schist. This some instances, quite inverted. Sections of vertical position you operation is well developed both at St. Agnes, and St. Michael's may find at Alum Bay, in the western end of the Isle of Wight; Mount in the Bay of Penzance. These and a thousand similar and, at Whitecliff Bay, in the eastern end of it. The same also instances prove that powers exist in nature which are capable may be seen near Welshpool, in North Wales, where Powis of transforming sedimentary and fossiliferous rocks into crystal Castle is built upon Silurian strata almost perfectly vertical. line strata.

In fig. 7, A B is the earth's crust. CD, the sedimentary rocks It has been intimated that in altering rocks, heat not only resting on it. F, a dislocated portion of the altered beds e, changes their appearance or aspect, but also gives them a new and separated from them by the eruptive rock @, which has mineral character, and causes them, in some instances, to be- been thrown up to the earth's surface by the subterranean come identical with the melted rock which has changed them, heat u. though they themselves have not been meited. Chemists have The study of fig. 7, will -help you to apprehend the nature proved by experiment, that a rock need not be perfectly melted of geological reasoning. Suppose that a geological student before its component parts will re-arrange themselves,--that is travels from c to a, along a sedimentary rock. At a he comes before they crystallise, or take a new mineral character. | to a rock of a different mineral character, and may be in diffiSedimentary rocks, therefore, inay be completely altered, with culty to account for it. As he walks over F, or passes alongout having the lines of their stratification obliterated.

side of it, and has the face or section of F on his left hand as he This theory will help you to understand a phrase often used walks towards d, he may not understand the new rock, till he by geologists, when they speak of “one rock passing into comes to b. Here he finds the Plutonic rock G, say granite or another," and that bv imperceptible gradation. If you imagine porphyry, evidently of igneous origin. He goes over, or by

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the side of a, till he comes to c, where he finds the same rock

RESUME OF EXAMPLES. over which he travelled from o to a. He now conjectures, and then reasons out, the conclusion that the rock a fb is a portion Connaissez vous le monsieur qui Do you knoro the gentleman who of the beds CD, first altered by heat, and then tilted up by the parle à notre cousin ?

speaks to our cousin ?

I know him who speaks to him. eruptive rock brc. He also argues with perfect certainty ; Je connais celui qui lui parlo. first, that if he could follow a down to its depth or origin, he comprenez vous ce que je vous dis ? Do you understand v'at I say to you ?

Who has spoken to you of this affair would find that eruptive rock to be eontinuous to the heated Qui vous a parlé de cette affaire ? reservoir at 1 ; and secondly, that if, between cand d he could L'Anglais dont vous parlez est ici. The Engiishman of whom you speak is

here. sink a pit to the

lowest line of ce, he would be sure to come L'Espagnol dont la sour est ici. The Spaniard whose sister is here. to the altered beds of which he had a specimen in a fb.

Que faites vous ce matin ?

What do you do this morning? In the few lessons already given you, I have endeavoured to Que dites vous à notre ami ? What do you say to our friendl ? place in your mind the two great principles of geology: first, Nous faisons ce que vous nous dites. We do that which you say to us. that the earth's crust is a fabricated article, produced in the Pour qui faites vous cet habit ? For whom do you make this coat ! laboratory of a stupendous chemistry, according to the fixed De quoi parlez vous à votre frère ? Of what do you speak to your brother?

We do what we can. laws of the supreme Contriver and Intelligent Maker of the Nous faisons ce que nous pouvons. whole; and secondly, that the article thus fabricated has been Nous parlons de ce dont vous parlez. We speak of that of which you speak. from the beginning, and at successive periods, disturbed,

EXERCISE 59. altered, and dislocated by agencies from within itself.

Arriv-er, 1. to arrive. Habillement, m, dress, Plaisir, m. pleasure, In the course of the lessons on which you are next to enter, Avec, with.

clothes

Presque, almost. you will find how the crust of the earth has been affected and Coffre, m.trunk. Hollandais, e, Dutch. Rien, nothing. modified by volcanoes, by the waters of seas and rivers, by Command-er, i, toorder. Linge, m. linen. Soulier, m, shoe. organic life, by vegetation, by ice and snow, and by other Ecossais, e, Scotch. Monsieur, m. gentleman. Vrai, e, true. means and agencies.

Enfant, m. child. Nom, m, name.

1. Qui connaissez vous ? 2. Nous connaissons les Hollandais

dont vous nous parlez. 3. Quelles leçons apprenez vous ? LESSONS IN FRENCH.-No. XIV. 4. Nous apprenons les leçons que vous nous recommandez. 5.

Ce que je vous dis est il vrai. 6. Ce que vous nous dites est By Professor Louis FASQUELLE, LL.D.

vrai. 7. De qui nous parlez vous? 8. Nous vous parlons des SECTION XXX,

Ecossais qui viennent d'arriver. 9. Savez vous qui vient

d'arriver: RELATIVE PRONOUNS (§ 38).

10. Je sais que le monsieur que votre frère connait

vient d'arriver. 11. Vos sæurs que font elles ? 12. Elles ne 1. Qui, used as nominative, may relate to persons or to font presque rien, elles n'ont presque rien à faire. 13. Que things :

mettez vous dans votre coffre? 14. Nous y mettons ce que Les fleurs qui sont dans votre jardin. The flowers which are in your garden. nous avons, nos habillements et notre linge. 15. N'y mettez

2. Qui, used as the object of a verb, can only be said of vous pas vos souliers ? 16. Nous y mettons les souliers dont persons. It is used interrogatively with or without a prepo- nous avons besoin. 17. De quoi avez vous besoin? 18. Nous sition :

avons besoin de ce que nous avons. 19. Cet enfant sait il ce Qui votre frère voit il ?

Whom does your brother see! qu'il fait? 20. Il sait ce qu'il fait et ce qu'il dit. 21. Ne Be qui parlez vous ce matin P Of whom do yont speak this morning? voulez vous pas le leur dire ? 22. Avec beaucoup de plaisir.

3. Que may be said of persons or things. It can never be 23. Faites vous ce que le marchand vous commande 24. Nous understood, and must be repeated before every verb (Sect. faisons ce qu'il nous dit., 25. Il parle de ce dont vous parlez.

EXERCISE 60. 18. 1]. Les personnes que nous voyons. The persons whom we see.

hat (ce dont) you want! 2. We have what Lee langues que nous apprenons. The languages which we learn, we want. 3. Is the gentleman whom you know here: 4. 4. Ce que is employed for that which, or its equivalent what : The lady of whom you speak is here. 5. Is she just arrived

[Sect. 25. 2.) 6. She is just arrived. 7. Do you know that Ce que vous apprenez est utile. That which you learn is useful.

gentleman? 8. I know the gentleman who is speaking with Trouvez vous ce que vous cherchez. Do

you find what

your father. 9. Do you know his name? 10. I do not know 5. Que answers to the English pronoun what, used absolutely his name, but I know where he lives (demeure). 11. What do before a verb:

you do every morning? 12. We do almost nothing ; we have Que pensez vous de oela ? What do you think of that?

very little to do. 13. Does the tailor make your clothes? 6. Quoi, when not used as an exclamation, is generally pre- 14. He makes my clothes, my brother's, and my cousin's. 16.

Do ceded by a preposition, and relates only to things :

you

know what you say? 16, I know what I say, and De quoi voulez vous parler ? of what do you wish to speak ?

what I do. 17. Do you know the Scotchman of whom your

brother speaks? 18. I know him well. 19. What does he A quoi pensez vous ? Of what do you think !

put into his trunk: 20. He puts his clothes. 21. Is that 7. Lequel, m. laquelle, f. lesquels, m.p. lesquelles, f.p. which you say true? 22. What I say is true. which, or which one (Seet. 17. 6], or which ones, relate to per- understand that which I say to you? 24. I understand all sons or things. They may be preceded by a preposition :

that you say. 25. Of whom does your brother speak. 26. Lequel avez vous apporté ? Which one have you brought ?

He speaks of the gentleman whose sister is here. 27. Is Duquel parlez vous ? Of which one do you speak I

your brother wrong to do what he does ? 28. He cannot be 8. Dont, of which, or of whom, whose, may relate to persons wrong to do it. 29. What are you doing? 30. I am doing or things, in the masculine or feminine, singular or plural. It that which you do. 31. Where do you put my books? 32. can never be used absolutely, and must always be preceded by Into (dans) your brother's trunk. 33. Is your brother here: an antecedent. It is preferable to de qui or duquel, &c. 34. He is not here. 35. He is at my brother's, or at my Les fleurs dont vous me parlez. The flowers of which you speak to me.

father's. Les dernoiselles dort votre sæur vous The young ladies of whom your sister

SECTION XXXI. parle. speaks to you.

1. The verb mettre is used in the same sense as the English 9. PRESENT OF THE INDICATIVE OF THE IRREGELAR Verbs. to put on, in speaking of garments, Mettre le couvert, means DI-RE, 4. to say. FAI-RE, 4. to make, to do. METT-RE, 4. to put.

to lay the cloth, or set the table :Je dis, I say, do say, or Je sais, I make or do, I Je mets, I prit, do put, Votre frère met son habit noir.

What hat do you put on!

Quel chapeau mettez vous ? am saying.

Your brother puts on his black coat. am making or doing. or am putting. Tu dia, Tu fais, Tu mets,

Le domestique va mettre le couvert. The servant is going to lay the cloth, Il dit, Il fait, Il met,

2. Oter means to take off, to take away, to take out :--
Nous disons,
Nous faisons,

Nous mettons, Mon domestique ôte son chapeau. My servant takes off his hat.
Vous dites,
Vous faites,
Vous mettez,
Otez ce livre de la table.

Take away that book from the table.
na disent,
Ile font.
Ils mettent

N'a-t-on pas êté le diner? Have they not taken aroay the dinner!

1. Have you

you seek?

23. Do you

UL.

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mauteau ?

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este w in the sense coat made. 13. I am going to have a coat and a vest made.

14. Does your brother have his boots mended? 15. He has too weter dare a house built.! them mended. 16. What does your son mean: 17. I do not ***** hus one built.

know what he means. 18. Is he angry with me or with my wawise before its own infini- brother? 19. He is neither angry with you nor with your

brother. 20. Is he afraid to spoil his coat? 21. He is not I have a cloth coat made.

afraid to spoil it. 22. Does the druggist want money? 23. You have leather shoes made.

He does not want money. 24, Has your sister taken my book cus.ui tollowed by dire is used in the sense do you take off your shoes ? 27. I take them off because

from the table? 25. She has not taken it away. 26. Why

they hurt me (gênent). 28. Do you intend to have a house due What do you mean?

built: 29. I intend to have one built. 30. Does the tailor www bout elle dire ? What does your sister mean?

spoil your coat? 31. He does not spoil it. 32. Who spoils RÉSUMÉ OF EXAMPLES.

your clothes! 33. No person spoils them. 34. What hat do

you wear? 35. I wear a black hat. No wettez vous pas vos habits ?

you not put on your clothes 1 J'ai pour de los gator,

I am afraid of spoiling them.
No porta vous jamais votre habit Do you never wear your black coat 1

LESSONS IN GEOMETRY.—No. VII.
Je lo mels tous les samedis.

I put it on every Saturday. Pourquoi n'ótez vous pas votre Why do you not take off your cloak? Having, in the preceding lesson, given some account of the nature

of the apparatus and instruments used in surveying, we now pro. J'ai trop froid, j'ai peur de l'ôter. I am too cold, I am afraid to take it ceed to explain more particularly the nature of their application

off

to actual practice. Let us begin with the most simple,-namely, the Faites vous raccommoder vos sou. Do you have your shoes mended ? chain and surveying cross. A B C D E F G H I is the representation of a liera ?

field, and of the manner of measuring Je fais raccommoder mes habits. I have my clothes mended.

a base line within it, and the perpenJe fais faire une paire de bottes, I have a pair of boots made. Je fais creuser un puits. I have a well dug.

diculars drawn to it from every corner. Votre frère que veut il dire ? What does your brother mean?

This figure is divided into several tri. Que veut dire cela ? What does that mean?

angles and trapezoids, and their sides Cela ne veut rien dire. That means nothing.

are taken parallel to each other, and Otez vous vos souliers et vos bas ? Do you take off your shoes and slock.

perpendicular to the base-line, on each ings 1

side. The method of measuring in Je n'ote ni les uns ni les autres. I take off neither these nor those.

the field is as follows :- Set up a Le diner est prêt ; le domestique va Dinner is ready; the servant is going picket or station-staff at each end of the base-line to be measured mettre le couvert.

to lay the cloth. Voulez vous ôter le couvert ? Will you take away the things from the direction from A to i, nsing the sights of the cross for the

that is, at A and E, and beginning at a, measure with the chain in

the table ? Je vais mettre le couvert. I am going to lay the cloth.

purpose of preserving the measurement constantly in that direcJe vais ôter le couvert.

tion. I am going to take away the things.

While this process advances, find, by the use of the cross,

the different places along the base-line where perpendiculars would EXERCISE 61.

be drawn to it from the several corners or bends in the boundary Apothicaire, m. drug. Gât.er, 1. to spoil. Prêt, e, ready.

of the field on both sides,- viz., from 1, 1, Q, and F, on the one gist.

Gilet, m. waistcoat. Raccommod-er, i, to side ; and from B, C, and o, on the other side. These perpenAprès, after. Grand, e, large, very.

mend.

diculars are to be measured at once by the chain as soon as their Cave, f. clar.

Manteau, m. cloak. Tout-à-l'heure, imme- places are found, by using the sights of the cross, before the rest of the Creus-er, 1. to dig. Noir, e, black.

diately.

base-line is measured, in order to save time and ensure accuracy. The Dimanche, m. Sunday. Pantoufle, f. slipper. Uniforme, m. uniform.

proper places from which they are to be measured, will be found by Diner, m. dinner. Pourquoi, why. Velours, m. velvet. Fâché, e, sorry, angry.

the cross after a few trials, by viewing both ends of the line through

one pair of sights, and the corners or bends in the boundary of the 1. Le général N. met il son uniforme ? 2. Il ne le met field, through the other pair of sights ; for it will be impossible to point. 3. Pourquoi ne portez vous point votre manteau noir? see the extremities of the base-line A and e, and any corner such 4. J'ai paur de le gâter. 5. Mettez vous vos souliers de satin as G, to which the measurement is to be made, or the picket placed tous les matins ? 6. Je ne les mets que les dimanches. 7. there, unless the exact spot as d, of the perpendicular a d is found. Il est midi; le domestique met il le couvert? 8. Il ne le met In measuring these perpendiculars a 1, CR, & G, and fr, on the one pas encore ; il va le mettre tout-à-l'heure. 9. Le dîner n'est side ; and 6 B, gc, and e D, on the other; one of the assistants keeps il pas prêt? 10. Le domestique ôte-t-il le couvert? 11. Il a book to record the observations as they proceed. Sometimes a ne l'ôte pas encore, il n'a pas le temps de l'ôter. 12. Otez rough sketch is made of the field as it appears to the eye, or as it vous votre habit quand vous avez chaud: 13. Je l'ôte quand is suggested by the measurements, and the measurements are j'ai trop chaud. 14. Faites vous faire un habit de drap? 15. marked on the corresponding lines drawn on the sketch. Both Je fais faire un habit de drap et un gilet de satin noir. 16. Ne are useful, and both should be practised. The following is the form faites vous paint raccommoder vos pantoufles de velours ? 17. of the field-book in the present instance, where the measurements Ne faites vous pas creuser une cave? 18. Je fais creuser une are marked in links of a chain. grande cave. 19. L'apothicaire que veut il dire? 20. Il veut dire qu'il a besoin d'argent. 21. Savez vous ce que cela veut dire : 22. Cela veut dire que votre frère est fâché contre vous.

Base-line A E. Offsets. Right. 23. Avez vous envie de mettre votre manteau ? 24. J'ai l'intention de la mettre, car j'ai grand froid. 25. Je vais l'ôter,

station A car j'ai chaud.

200

530 EXERCISE 62.

630 Ab 210 1. Do you take off your coat? 2. I do not take of my

900

700

560 coat, I put it on. 3. Do you take off your cloak when you

1010 are cold? 4. When I am cold I put it on.

1400
do

1020
370

1770 little boy take off his shoes and stockings ? ($ 21 (4).] 6. He

1960

600 takes them off, but he is going to put them on again (remettre).

fr

2230 7. Does that little girl lay the cloth? 8. She lays the cloth every day at noon (midi). 9. Does she take away the things from this field-book, the necessary numbers for calculating the after dinner? 10. She takes away the things every day. 11. contents or area of the field are easily found, and the computations Do you intend to have a coat made ? 12. I intend to have a made in the following manner.

FIELD-BOOK.

Offsets. Left.

A a

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b B

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Ас

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А д.

5. Does your

Ad
Ae

e D

A E

Base A a

4

First, for the areas on the right of the base line :

Here the perpendicular distance g e is found by subtracting the
Ist. For the area of the triangle a a

length of A g from that of 4 e: thus, 1770—1010=760.
Offset or perpendicular a i
530

4th. For the area of the triangle de E.
200

Offset, or perpendicular e D 370 106000 product.

Base e E

460
Double area of the triangle A Q I
2nd. For the area of the trapezoid a i e c.

222
Offset or parallel side a i 530

148 Offset or parallel side c H 700

Double area of the triangle D e E 170200 product. Sum of the parallel sides 1230

The base e E is found by taking a efrom A E; thus 2230-1770=460. Perpendicular distance a c 650

Double areas on the left of the base line. 615

Of the triangle a b B 111300
738

Of the trapezoid b Bcg 872000
Of the trapezoid gc De

706800 Double area of the trapezoid a rhc 799500 product.

Of the triangle d e E 170200 The perpendicular distance here a c is found by subtracting the

Sum of these double areas 1860300
length of A a from that of AC; thus 850–200=650.
3rd. For the area of the trapezoid c H G d.

Sum of double areas on the right 2920700
Offset or parallel side c H 700

Sum of double areas on the left 1860300
Offset or parallel side d G 1020

Sum of double areas in all 4781000
Sum of the parallel sides 1720

550
Perpendicular distance c d

2) 4781000

Area of the field 2390500 square links.
860
860

Now as a square chain is 10000 square links; for 100 x 100=

10000. And as 10 squares make an acre; it is plain that 100000 Double area of the trapezoid c HG 946000 product.

square links make an acre. Hence, the following simple operation The perpendicular distance here cd is found by subtracting the for converting the square links into acres, roods, poles, &c. length of A c from that of Ad; thus, 1400-850=550.

Acres 23,90500
4th. For the area of the trapezoid d G F f.
Offset or parallel side d G 1020

600
Offset or parallel side f F

Roods 3, 62000

40 Sum of the parallel sides 1620

560 Perpendicular distance d f

Poles 24,80000

301
972
810

2400000

20000 Double area of the trapezoid d G F f 907200 product. The perpendicular distance here d f is found by subtracting the

Square yards 24,20000 length of A d from that of a f; thus, 1960-1400=560.

Area of the field A B C D E F GI, 23 ac., 3 ro., 24 po., 24 sq. yds.
5th. For the area of the triangle f F E.
Offset or perpendicular f r 600
Base f E 270

LESSONS IN LATIN.-No. XIV.
Double area of the triangle f F E 162000 product.
The base f E, is thus found; take a f from A E, 2230--1960=270.

By John R. BEARD, D.D.
Double Areas on the right of the Base line.

THE LATIN VERB.
Of the triangle A Q I

106000

In form, the Latin verb has two chief divisions-1, active ; 2, Of the trapezium a inc 799500

passive. Thus laudo is I praise, in the active voice, and laudor, Of the trapezium cu gd 946000

I am praised, in the passive voice. There are some verbs which, Of the trapezium dorf 907200

though passive in form, are active in signification; as, hortor, 1 of the triangle f F E 162000

encourage. The ending in r shows that hortor is of the passive Sum of these double areas 2920700

form. This form, the verb, so to say, lays down, or lays aside, Next, for the areas on the left of the base line :

and hence it is called deponent (from de, down, and pono, I Ist. For the area of the triangle a b B.

put). Deponent verbs, then, are words which, disregarding Offset or perpendicular 6 B 530

the claims of their form, have an active import, just as if they Base a b 210

were active in form. As these verbs have an active meaning,

their past participle has an active meaning; e.g.-hortatus, the 53 106

past participle of hortor, is not being encouraged, but having

encouraged. This past participle joins with parts of the verb Double area of the triangle A b B 111300 product. sum I am, to form the perfect tense ; thus, hortatus sum, 2nd. For the area of the trapezoid b Bcg.

means I have encouraged. There are deponent verbs in all four Offset or parallel side 6 B 530

conjugations. Offset or parallel side g c 560

The tenses of the verb in Latin are pretty much the same as

in other languages. Sum of the parallel sides

Thus we have PRESENT, amo, I love, or I 1090 Perpendicular distance bg 800

am loving ; IMPERFECT, amabam, I was loving, or I did love ; PER

FECT, amavi, I loved, or I have loved ; PLUPEKFECT, amaveram, Double area of the trapezoid b Bcg

872000 product. I had loved ; FIRST FUTURE, amabo, I shall or will love ; SECOND Here the length of the perpendicular distance bg is found by sub- FUTURE, amavero, I shall have loved. tracting the length of A from that of Ag: thus, 1010—210=800. The present tense denotes either an action continued in the 3rd. For the area of the trapezoid g c De.

present time, or an habitual action. The imperfect tense denotes Offset or parallel side gc

560

an action continued in past time. The perfect tense has two Offset or parallel side e D 370

meanings ; first, it signifies an action done and completed in Sum of the parallel sides 930

past time indefinitely, and from the period in past time being Perpendicular distance ge 760

indefinite or undefined, it is called an aorist, or is said to have

an aorist import; (aorist is a Greek word, denotes a tense of . 558

the Greek verb, and signifies undefined, or indeterminate ;) in the 651

second place, the perfect tense indicates an action which, in Double area of the trapezoid y c d e 706800 product. itself, or in its consequences, continues from the past to the

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