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Επος

er-e'mos

GREEK STEMS.

Stems, a word

ep

erem
a work
metal

metall
a custom

eth

er'-gon

Eθος

eth'-os

Ev

eu or you

a messenger

gen Oxy

orygen.

water

Γενος

Γλωσσα
Γλωττα
Πολυς
Γωνια

gon

「 'EF

hex

a letter

Επι

to write

properly represent them according to the circumstances under of terms, as a means for the expression of your thoughts and which they are placed, may certainly claim the title of a feelings. draughtsman in its fullest meaning.

These remarks find verification in the study even of the In arranging the positions of the head and features, we must remnants of Greek which form part of our English speech. bear in mind that the general form of the head is oval. This If ours is a rich language, if ours is an expressive language, figure may be applied with great advantage in two ways, both we owe a large debt of gratitude to the Greek. By the aid of which we will consider. As the oval which represents the which it affords, we express thoughts which we could not other form of the head is a solid, and the several lines which we are wise have expressed ; and we acquire ideas, and modifications about to draw, to determine the proportions and positions of of ideas, the sources of which are found only in its literature. the features, are supposed to be drawn on the surface, there. In exemplification, it suffices to refer to the single domain of fore the perpendicular line drawn throughout the length in theology. The creed of Christendom wears the shape and the Fig. 129, Lesson XXI., will decide the position of the face to hue which it received from the Greek language, in which the be parallel, that is, a full face. In a retiring view this same Gospel was promulgated to the world, and by which it was line will be a curve, as A B in Fig. 136, upon which the features planted in the mind of all the most civilised nations. must be arranged as in Fig. 137. When the head is looking up or down, then all the lines which are straight in Fig. 129 Greek Words. Pronunciation. Meanings.

English Words. become curved in proportion to the extent of the inclination

ep'-os

orthoepy, qic. of the head. Figs. 138, 139 will illustrate these positions, and Ερημος

a desert

eremite (hermit). show that the use made of the curved lines is the same as that Εργον

erg (urg)

energetic. employed in the full face. Regarding the treatment of the Metalov met-al-lon

metallurgy. details, more especially the peculiarities belonging to each

ethics. feature, the pupil must be left in a great measure to his own

seu eulogy.

well observation and practice from nature and from casts. In the

evangelist. details no two faces are alike; consequently, there can be no Αγγελος an'-gel-os*

angel

angel. special rules in reference to them. We must treat the subject

Γαστηρ
gas'-teer

the belly gastr gastric. as a whole, and use those rules only which are applicable to

Γενναειν gen-na'-ine to produce

genesis. all, with regard to proportion and position. We may say, for

οξυς Ox'-uso sharp instance, that the length of the month is equal to the width

'Yowp hu'-dor

hydro hydrogen. gen'-os

kind between the eyes; that the centre of the mouth is one-third

gen heterogeneous. 'Etepos

het'-er-os another's from the bottom of the nose to the lower part of the chin.

hetero heterodox. glow'-sal

Sgloss glossary, These and other regulations may be useful where a classical

glowi-tas
a tongue

glott polyglot. head only is attempted, and it is right to know them; but

pol'-use many

poly polygon. Nature does not always carry out these exact dimensions, other

go'-ni-a an angle

goniometry. wise we should lose that individual character so admirable,

six

hexa hesagon. and in most cases indispensable to real beauty. The know

Γραμμα gram'-ma

gram grammar. ledge of these proportions will help us to avoid extreme de

ep'-i
upon

epi epigram. formity, and many absurdities; it will likewise quicken our per- θαλαμος thal-a-mos a bridechamber thalam epithalamium. ception when studying the characteristic differences existing Γραφειν graph'-ine

graph autograpk. amongst heads; consequently, this knowledge, coupled with close observation regarding the angles of the face, and of the

The aid which the Greek language affords to the student in features one with another, and more minutely those angles making exact verbal distinctions is illustrated in orthoepy

, which constitute the form of each feature singly, will together which is, by its derivation, seen to designate right speaking, as enable the pupil very quickly to acquire a power of giving cha- orthography is right writing; the first, therefore, refers to proracter and individuality to his subject, either in portraiture nunciation, the second to spelling. or when engaged on an ideal head representing some passion "The epic poem is a discourse invented by art to form the manners or emotion of the mind. What rule could be furnished for by such instructions as are disguised under the allegories of some one drawing a Roman or a snub nose, beyond that of marking important action, which is related in verse after a probable, diverting, the angle which gives character to the shape of the nose ?

and surprising manner.”—Pope. Nothing would prevent originality of drawing and a true feel

The three great epics are Homer's “Iliad,” Virgil's “ Æneid,” ing for Nature more effectually, than confining the practice in and Milton's “Paradise Lost.” Such is the perfection of these all cases to set rules for details. Because Nature is varied in poems that they form a class by themselves. her details, therefore it is in generalities only that rules are

“ Three poets, in three distant ages born, useful, and where it would be unwise to reject them.

Greece, Italy, and England did adorn."
The formation of our hermit, from the Greek Epnutis

(o-re'-mi-tees), illustrates the change which words undergo in LESSONS IN ENGLISH.-XXVI.

passing from one language to another. GREEK STEMS (continued).

Metallurgy, an incomprehensible term to the ordinary English

student, discloses its meaning by its own act to those who know The learning of a new language is like the acquisition of a new the import of its component parts. Metallurgy is, in general

, sense. This is true, if only because a new language affords a the art of working metals-that is, the extraction of metal from new set of means for the expression of our ideas. The capacity the ore. of the human mind is greater than is the power of expression Ethics is the science of morals—that is, of right feeling and possessed by any vocabulary. That greater capacity finds a right doing. The word ethics resembles the word moral in new channel, and a new outlet, in a new language. Besides, origin. They both signify customs, and they intimate that with language is a medium for conveying ideas to a recipient, as well the ancient Greeks and Romans, what is customary was what as an instrument for the expression of ideas already enter- is right. At the bottom of such a notion there must have been tained. With words, then, yon gain ideas. The increase of a a low standard of morality. Thus does a knowledge of language man's vocabulary is the augmentation of his mental treasures. open to our eyes the character of nations. The termination of New knowledge must run into the old moulds. If it be true ethics,

like physics, mathematics, etc., denotes a science. Ethics that no idea no word, equally is it true that no word no idea is the science of morals. You may, indeed, make a word contain more than it does con. Evangelist is, according to the derivation, the bearer of over tain. You may transmute brass into silver, and silver into news. The Greek word for gospel-namely, evayyedcov (eu-22gold; but out of nothing comes nothing. There are, then, gel'-i-on)-means good news. (Luke ii. 10.) two ways by which I may impart knowledge; I may give dea by giving a new word, and I may increase the of animals, is of all menstrua the most active, the most universal"

"The gastric juice, or the liquor which digests the food in the stomach he word you have. Equally may I aid the develop. Paley, "Natural Theology." ir mind, and augment at once its knowledge and 'y supplying you with a fresh term, or a fresh series * In Greek, when two g's come together, the first sounds like A.

"Oxygen is a principle existing in the air, of which it forms the hecatombs of most happy desires, praying all things may prove prosrespirable part, and which is also necessary to combustion. Oxygon, perous unto you.”—Drummond. by combining with bodies, makes them acid, whence its name, signi.

Isothermal lines are lines of equal heat in different parts of fying generator of acids.”—Todd's Johnson.

the globe. Iso is also found in isosceles (okelos, skel'-os, a leg), Hydrogen is water-producer. Hudor (sowp), in its form hydro, applied to a triangle which has its two sides of the same length. is found also in hydrocephalous (Greek, Kepaan, keph'-a-le, the

Aphelion is that point of the orbit of a planet in which it is head), having water in the head (the brain); and in hydro- most distant from the sun ; perihelion is that point in which it phobia (Greek poßos, phob-os, fear), water-madness. Hydropsy, is nearest to the sun. water-sickness, is shortened into our dropsy.

Anything whose duration or existence is very short is termed "Soft, swollen, and pale, here lay the hydropsy,

ephemeral, or lasting for a day. Thus, insects that spring into Unwieldly man, with belly monstrous round.”

life at sunrise and perish at sunset are styled ephemera. Thomson, Castle of Indolence."

“There are certain flies that are called ephemera, that live but a Hydrography is properly the opposite of geography; for as

day."-Bacon. the latter, considered in its component parts, is a description of the land, so the former is a description of the water.. By usage account of daily transactions. Ephemerides (the plural of ephe

An ephemeris is properly a journal (French, jour, doy), an these significations are modified, so that geography, signifying a description of the surface of the earth, comprises hydrography, meris) denote a set of astronomical tables, showing the state of

the heavens for every day. which describes, by maps, charts, etc., the surface of the water, and especially the sea-coast, with its rocks, islands, shoals, and of Geometry,” in reference to lines and angles that correspond

The expression homologous is used by Euclid in his “ Elements shallowe.

in relative position, proportion, or structure : hence any two "Christopher Columbus, the first great discoverer of America, was

forms or expressions that exactly correspond in position, proa man that earned his living by making and selling hydrographical portion, formation, or value, may be said to be homologous. maps." --Chambers,

“Comparing the homologous or correspondent members on both sides, By derivation, grammar is the science of letters. This is not

we find that the first member of the expression," etc.-Bishop Berkeley, an incorrect definition, for the science of letters, considered in

“ Analyst.” all its relations, is the science of language, of which letters

Apocalypse, by its very derivation, signifies uncovering ; in are the elementary portions. “Letters” is often used, how, Latin it is unveiling—that is, revelation. ever, for systematic knowledge, or the results of a high and

In apocrypha we have another theological term, which is varied education. So we speak of “ a man of letters." In this interpreted to mean a hidden writing, from ano (ap-o), from, and sense the term is used in the question, “How knoweth this man letters, having never learned P” (John vii. 15.) The hostile KPUTTEIV, krup-tine (cryph), to hide. But why should not the

apo here have the same meaning as in apocalyse, and so reverse questioner took Jesus to be ignorant (Acts iv. 13)—that is, as

the import of kryptein (English crypt), to hide, and thus signify in the original, id.wins (id-i-o'-tees), idiot, untaught—such as

the disclosed, discovered, or detected writing ? Any way, Peter and John were accounted.

apocryphal is equivalent to spurious, and opposed to canonical "I made it both in forme and matter to emulate the kind of poeme

or authentic. which was called epithalamium, and by the ancients used to be sung

“Now, beside the Scriptures, the bookes which they called ecclewhen the bride was led into her chamber."— Ben Jonson, “ Masques.”

siasticall were thought not unworthy sometimes to bee brought into Greek Words. Pronunciation, Meanings. Steins. English Words.

publicke audience; and with that name they intituled the bookes which ' 'Agios hag'-i-os holy

hagio hagiography.

we term apocryphal.”—Hooker, " Ecclesiastical Polity."
hek'-a-ton hundred hecato hecatomb.
bous

hecatomb.

Laity denotes the people as contradistinguished from the he-li-os

the sun
helion aphelion.

clergy. In ancient times the laity were ignorant, the clergy per'-i

peri
perihelion,

learned. Hence arose a broad contrast, exhibiting the people as ap'-o

from
ap apology.

wicked as well as untaught, and the clergy (clerks) no less holy “ 'Huepa he'-mer-a a day

hemer ephemeral. than instructed. These usages are found in the substance of hep'-ta

hept

heptagon. our language, and still linger amongst us in both thought and “ "lepos hi'-e-ros holy

hiero hieroglyphics. feeling. Γλυφειν glu'-phine

to engrave

glyph glyphography. "He entended (intended) to set forth Luther's heresy, teaching a horse

hippo hippopotamus. that presthed (priesthood) is no sacrament, but the office of a lay-man Ποταμος pot'-a-mos

a river

potam Mesopotamia. or a lay-woman appointed by the people to preache."-Sir T. More. bod'-os a way exodus.

“No wonder though the people grew profane, Ex, ef ek, ex out of exorcism.

When churchmen's lives gave laymen leave to fall.”—Drayton. hom'-os

homo homologous.
hu'-gros

wet
hygro hygrometer.

Synthesis is properly the putting together, as analysis (ava, Ιχθυς ik'-thuse

a fish
ichthy ichthyology.

an'-a, up; and Avelv, lu'-ein, to undo, to loosen) is the undoing. loos is'-os

equal
iso isothermal.

A watchmaker performs an act of analysis when he takes a Κακος kak'-os bad

cacophony.

watch to pieces, and an act of synthesis when he puts the parts phone

a sound
phono phonography.

together again.
kali-os

beautiful

cali
caligraphy,

“ Synthesis consists in assuming the causes discovered and estaKaavat ka-lūp-to

calyp apocalypse. blished as principles, and by them explaining the phenomena proceedkos'-mos

the world kosm microcosm. ing from them, and proving the explanations."-Newton, Optics." Κυκλος ku'-klos

a circle
сусl cyclo.

“ Analysis consists in making experiments and observations, and in la'-os

the people
lai laity.

drawing general conclusions from them by induction."-Ibid.
mon'-os
alone

monosyllable.

Analysis is the way of discovery, synthesis is the way of synthesis. with •

teaching or communication. By synthesis men put together and syllogism. syl

exhibit what they have ascertained by analysis. Λαμβανειν lam'-ba-nine to take

lab syllable.

Afetamorphosis denotes a change of form.
the-sis a placing
(thet synthetic.

"Thus men (my lord) be metamorphosod
mor-phe shape morph metamorphosis.

From seemly shape to byrds and ougly beasts.”—Gascoigne. S change meta metathesis,

Metempsychosis (ueta, meta, change ; ev, en, in; and yuxn, met'-a met method.

psu'-ke, the soul) has for its Latin equivalent transmigration Μυθος mu'-thos şa speech myth mythology.

(trans, over ; migro, I change my place). a fable

“The sages of old live again in us, and in opinions there is a metemnek'-rog doad

an 0.3

b

Εκατον Bous “Ηλιος Περι λτο

near

“Επτα

seven

“Ιππος

hip’-pos

οδος

od

ex

the same

'Ouos Υγρος

oaco

Duvn Καλος

I cover

Κοσμος

Aaos

Movos

mono

syn

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necromancy.

psychosis. We are our re-animated ancestors, and antedate their Μαντεια

man-tei'-a divination mancy geomancy. resurrection."-Glanvill. A hecatomb is the slaughter of a hundred oxen in sacrifice. Metathesis is a change of position or a transposition. It is sometimes used metaphorically, as, for example :

what we write bird was formerly bryd, the i and the "And here, sir, she offers by me to the altar of your glory, whole places.

Nexpos

necro

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Mythology is the science of fable, and is applied to the religion and opposite forces—the weight of the water above it, and the of the Greeks, the Romans, the Hindoos, etc., in opposition to upward pressure of that below it. Now the former is clearly the pure religion of the Gospel. German philosophy has intro- equal to the weight of a column of water having, like a , an duced amongst us the new term myth, as denoting a legend, or area of 1 square inch, and whose height is equal to G K. If a version of facts, shaped and coloured by' opinion,

fancy, preju. G u be now sunk to a lower level, it will have to sustain the dice, by the workings of the intellect, the workings of the weight of a longer column, and therefore imagination, or the workings of the heart. 'In origin, myth, the pressure of the water on it will be fable, and legend are one, for the words severally denote a word, greater. We see thus, that the pressure something spoken, something narrated. But as old stories soon increases with the depth. If we take a lose their primitive form, and acquire new shapes and hues, so number of bags of flour or sugar, and pile words pass into legends, and legends are corrupted into fables. them one on the top of the other, the

Necromancy is the fancied art of learning and disclosing facts lower ones have to sustain the weight of by communication with the dead. The witch of Endor dealt those above, and will accordingly be comnecromantically with Samuel at the request of Saul. (1 Sam. pressed to a greater extent than those xxviii. 7; compare Deut. xvii. 9.)

which are higher up in the pile, and thereEXERCISES IN COMPOSITION.

fore have to sustain the weight of fewer. P

Just in this way each layer of liquid has
Words with their Prepositions to be formed into sentences.

to sustain the weight of all above it, and
FOREIGN REPRESENTATIVES. thus the lower layers are more powerfully
Arrive at,
ripa, a river-side.

compressed. An illustration of the great
Ask of a person,

Fig. 5. pressure thus exerted is seen in the fact for or after a person, Yascian, to petition. for a thing,

that if a tightly-corked bottle be sunk to a depth in the sea it
Aspire to,
spiro, I breathe.

will be broken, or else the cork will be driven into it.
Assent to,
sentio, I feel.

We have now to show that this pressure is quite independent
Assimilate to,
similis, like.

of the shape of the vessel. Instead of that shown in Fig. 4, Associate with, socius, a companion.

let us have one made in the shape of a small tube fitted into Assure of, assurer, to assure.

the top of a larger one, as shown in section in Fig. 5. The Atone for, at one, to at-one.

pressure on the part directly under H E will, as before, depend Attached to, attacher, to bind.

on the height of the column of water above it. But every Attain to, atteindre, to reach.

part of the base, u x, must sustain the same pressure, for Attend to,

tendre, to stretch.
Averse to, from,
verto, 1 turn.

otherwise there would not be equilibrium, but the liquid would

move towards that part where the pressure was least. Every EXERCISES FOR PARSING.

part of a horizontal layer sustains then exactly the same presA pedagogue is a term of Greek origin, equivalent to our school. sure. We thus arrive at the apparently strange result

, that master. Pedagogue is a word which is now used contemptuously. if the vessels represented in Fige. 4 and 5 be filled to the same In an oligarchy the interests of a few predominate. In a demo- height, and the areas of their bases be equal, the pressure on cracy the interests of the many prevail. The real and the apparent each base will be the same, although one contains a much larger interests of men are sometimes very different. A polemical spirit is quantity of water than the other. We must not, however, undesirable. Polemical writings are occasionally required. character of the apostle Paul is very noble. Apostolical virtues are suppose that, since the pressures are equal, the vessels

, if placed mre. The apostles received their mission immediately from Christ. in opposite pans of a pair of scales, would balance each other

. Without enthusiasm the best of causes cannot be carried forward.

This paradox is easily explained. Suppose we have a bor, Enthusiasm is in danger of degenerating into fanaticism.

the lid of which fastens down by a catch, and we place a spiral spring inside, so that when the lid is closed the spring is

powerfully compressed, the pressure on the bottom is manifestly HYDROSTATICS.-II.

much greater when the box is closed than when it is open, and

yet it weighs no more. The fact is, the spring presses the top PRESSURE OF LIQUIDS

FROM THEIR WEIGHT

of the box upwards with exactly the same force as it presses CENTRE OF PRESSURE—LEVELS—SPRINGS AND ARTESIAN the bottom downwards, and these two forces neutralise each WELLS.

other. So in the vessel shown in Fig. 5, the pressure of the HAVING now mastered the principle of the equal transmission of liquid, being transmitted in all directions, presses up against pressure in all directions, we must pass on to notice the pressure the surface P GFR, and balances a part of the pressure on which is produced by the weight of the liquid itself. Water, in the base, and the pressure on the scale pan will be the difference common with all other substances, possesses weight, and this between these two, the upward pressure on P R being exactly weight must cause pressure on the sides of the vessel containing it. If we have an upright cylindrical vessel with straight sides, and place in it a cylinder just fitting, it will press on the bottom of the vessel with a force equal to its own weight. If now we replace the solid by a liquid having the same weight, the pressure on the bottom of the vessel will remain the same as before, but, in addition to this, every part of the sides of the vessel will sustain an outward pressure. This is clear from the fact that, if we remove the side, or any portion of it, the liquid

Fig. 6. will no longer retain its shape, but will spread A! itself out as widely as possible.

equal to the weight of the ring of water required to make up The first fact we have to notice about this the quantity there is in the other vessel. pressure is that it increases with the depth of The following experiment affords a proof of this principle of the liquid, and in the same proportion, but is the pressure being dependent alone on the area of the sur

: Fig. 4.

perfectly independent of the shape of the face and the depth of liquid. Procure three vessels of the

vessel containing it. In the proof of this shapes represented in Fig. 6, and let their bases be made of and other propositions, we shall make the following assump- exactly the same size, and arranged so as to open like trap-doors tion—that any portion of a bulk of fluid may be supposed by means of hinges. to become solid without making any difference in the state To a similar part of the base of each attach a string, and let of equilibrium of the liquid, or in the forces which act upon these pass over pulleys and have equal weights affixed to their it. A moment's thought makes this fact self-evident. Let ends, so as to keep the bottoms closed. BCD (Fig. 4) represent a vessel filled with water to the If now water be poured into each vessel it will be found that

AB. Take in it any horizontal layer, EF, and in this the bottoms will open, not, as might be supposed, when 90 portion, G H, having an area of 1 square inch, be equal weight of water has been poured in, but when the water ied to become solid. It is now kept at rest by two equal stands at the same level in each.

ARISING

[graphic]

с

A

H

seen,

M

We see thus, that when filled to the same height the bases Now, although the mean pressure is that at the centre of sustain exactly the same pressure, and this pressure is equal to gravity, we must not imagine that this point is the centre of the weight of the fluid in the middle vessel.

pressure-that is, that a support placed behind this would Having thus seen that pressure is proportional to the depth, balance the pressure. If we suppose the surface divided into We can examine the variations in it at the different parts of the layers, there will, if it be rectangular, be sides of any vessel or of an embankment. If we have a as many layers above the centre of gravity column of water having a base 1 square inch in area, the as below it; but, since the pressure is pressure on a layer of it at a depth of 1 inch will be equal to the greater on the lower layers than on those weight of a cubic inch of water, or 252.5 grains; and at a depth higher up, the larger part of the pressure of 2 inches the pressure will be equal to the weight of 2 cubic will be below the centre of gravity. The

Fig. 7. inches, and so on, varying in direct proportion to the depth. centre of pressure is therefore below this point. Its position

We see thus, that an embankment or sea-wall should also varies with the shape of the surface, but in a rectangular surincrease in thickness in the same proportion. The pressure face is situate at about two-thirds of the depth. This fact against such an embankment is, it may be observed, quite should be borne in mind in the construction of lock-gates, for independent of the extent of the body of water it sustains. if a hinge be placed near the top, and a pivot and socket at the The same strength is required to resist the pressure on the side bottom, an undue pressure is thrown on the lower support, and of a narrow mill-stream as in a sea-wall, provided the depth thus there is a tendency to wring or twist the gates. The supbe the same in each case.

ports should be arranged as nearly as possible equi-distant from If we divide the side of a rectangular vessel into any number the centre of pressure, one being near the bottom, and the other of equal divisions, the pressures at these divisions will be in about a third of the way from the top, as then the pressure is the proportion of the consecutive numbers 1, 2, 3, etc.

equally distributed. Let these divisions be one foot apart. Then at the first, the There is another property of liquids which results from the facts pressure on any portion will be equal to the weight of a column already noticed, and that is, that the surface always maintains of water one foot high. The pressure on a square foot at this its level and forms an horizontal plane. This fact is familiar to depth will therefore be equal to the weight of a cubic foot of us by every-day experience, water. We must not, however, suppose that this will be the and the reason of it is easily pressure on a square foot of the side extending from the sur

Let A B C D (Fig. face to the first division, for at the surface the pressure is 7) be & vessel containing nothing, and it gradually increases with the depth. The mean liquid, and let the surface bo pressure on the square foot is therefore equal to that at a depth supposed to have the figure of 6 inches, and the total pressure is equal to the weight of a да кв. Take any layer, column of water of this height. So if we want to know the pres- E F, in the fluid, and ima sure on the rectangular side of a vessel, we must ascertain its gining it to become solid, area, and multiply this by half the depth; we shall thus find the let us see what is the presnumber of cubic feet of water to which the pressure is equal. sure at each end of it. At

An example will make this clear. Suppose we have a vessel 5 E it is equal to that of a feet long and 4 broad, and it be filled with water to a depth of column of water having the 4 feet, what is the pressure on the four sides, and what on the height G E; at F it is equal

N bottom? We will take the sides first; each of these is 5 feet by only to the column F H. 4, and has therefore an area of 20 square feet; each of the ends The former of these is obhas also an area of 4 feet by 4, or 16 square feet. The total area viously greater, and thereof the two sides and the two ends is therefore 40 + 32, or 72 fore equilibrium cannot

Now the depth of the water being 4 feet, the exist till this difference is mean pressure is found at a depth of 2 feet, and thus the removed. The particles of total pressure on the sides is equal to a column of water 72 feet fluid will therefore move in area and 2 feet in height; that is, to the weight of 144 cubio from E towards F until the

Fig. 8. feet of water.

surface becomes eren. In these calculations we must remember the following Exactly the same result will occur if, instead of one vessel, weights:

we have any number communicating with each other, no matter A cubic foot of water weighs about 1,000 ounces, or 62} pounds. what their shape may be. The apparatus usually used for the A cubic yard weights of a ton.

proof of this is shown in Fig. 8. A number of glass vessels, A cubic fathom weighs 6 tons.

varying greatly in size and shape, but all having the same The total pressure on the sides is therefore 144 X 62} =9,000 height, are arranged so as to communicate freely with each pounds, or rather over 4 tons. The pressure on the bottom other. If now water be poured into any one of them, all will is 5 x 4 x 4, or 80 cubic feet of water. This is equal to be filled, and the water will rise in each of them to the same 80 x 62} or 5,000 pounds, which is nearly 2 tons.

height; or, if a stopcock be fitted at the bottom of each, and Sometimes the surface on which we want to ascertain the they be filled to different levels, immediately on the taps being pressure is not a rectangle, but we may always take the mean turned, the level will become the same in all. The mass of depth as that of the centre of gravity of the urface, and, water in m is many times greater than in n, yet it will stand at multiplying this by the area, we obtain, as before, the pressure. exactly the same height in

We thus see that when water has to be confined by a wall or each. embankment, the safest plan is to spread it out as widely as Familiar illustrations are possible so as to diminish the depth, and also to let the edges seen in tea-pots, or other vesgradually slope down to the middle. If the depth against the sels used to pour liquids from. embankment be great and a small leak occur—as it may, from The spout is always so arthe hole of a rat or some similar cause—the water, when once ranged that the open end of it it has found a way, soon wears a larger hole, and the upward is at least as high as the surpressure of the water is often so great as to blow up the bank. face of the liquid within. It is on account of the great pressure thus produced by a The practical applications of

Fig. 9. body of water that lock-gates have to be made so strong; and this principle are numerous to enable them to stand better, they are usually made so that and important. The most common is the lovel, which is such when closed they are in the form of an arch, the convex side an important instrument in surveying operations. In making being turned in the direction in which the water is highest. roads or railways, or still more in canals, it is necessary that all When the gates are large, a sliding panel, worked by a screw, parts should have as nearly as possible the same elevation, so is introduced near the bottom, and through this opening the as to avoid inclines. It is desirable, too, to do this with as little water flows till it stands at the same level on each side. With- labour as possible, and therefore that route is chosen

will out this the pressure would be too great to allow of the gates require least cutting or embankment. To ascertabeing opened.

ling is required. The form of level which

square feet.

principle, though not the one commonly used, is shown in Fig. 9.

ESSAYS ON LIFE AND DUTY.-XI. A glass tube is taken, and each end is bent right angles. This is supported on a stand, and water poured in so as to rise

ECONOMY. a little way in each limb. A float rests on the liquid at each PERHAPS there is no word in the English language that has end, supporting a framework with cross wires. A graduated been so foolishly narrowed in its meaning as the word Economy, pole is then set up at a distance, and the observer notes what Most people think of it as a saving of money, as though to be part of it is in a straight line with the points where the wires economical was, in a certain sense, to be stingy or mean. Now cross, and thus finds the difference in height between the place economy in its true interpretation is the art of management–is where the pole is and that where he stands.

the wise adaptation by which we arrange time, health, and The surface of the earth, however, is not a true level, but a strength so as to produce the best results. It is human curve which differs from a straight line by about eight inches in labour and opportunity wisely and well applied: not a mere a mile; an allowance to this extent has accordingly to be made, saving or hoarding, but rather a wise investment and expenfor the surface of water keeps to the curve, or natural level, as diture of what we have. The young man who saves the same it is called. In a small surface this is not noticed at all, but amount of money which his friend, who has equivalent means, we observe that when a ship is going out to sea the hull is spends in attending a French or German class, or in learning hidden by this curve, while the masts still remain visible. the rudiments of science, is in no sense economical. The day

The more common form of level consists of an even tube of will come when that knowledge of French or German will be of glass nearly filled with spirit, so that only a small bubble of far more value to him than all the money he saved up by not air remains in it. Both ends are then closed up, and it is paying for the learning of these languages. He will lose a higher mounted in a case, so that the sides of the tube are exactly appointment, into which his more cultured friend will step, and parallel to the bottom. If it be placed on an horizontal surface, will be obliged to drone on in the position he at first occupied, the bubble will remain exactly in the middle; but if either end because he is not fitted for a better. Time and opportunity be elevated at all, the bubble will rise to that end. In levelling, are now gone for ever, and were wasted whilst he saved his one of these levels is fixed to the stand of the telescopé so as little hoard of silver or of gold. to be parallel to it. It is then adjusted by means of thumb- Economy requires thought. We have to discern not only screws so as to be perfectly horizontal, and on looking through what to do, but the very best way of doing it; and this, too, in the telescope the elevation on the pole may be read off with every branch of life. Think of the positive waste that is conmuch more accuracy and at a greater distance than when the tinually going on-not through God's arrangements, for they are other form of level is used.

so perfect that there is not the smallest waste in all creationIt is on this principle of water always finding its level that but through man's short-sighted ignorance or wicked sloth! a town is supplied with water. If there be a convenient eleva- The late Lord Palmerston once cleverly remarked that DIET tion outside the town a reservoir is made there, and the water was only "matter in the wrong place :" & saying as true as it pumped up into it. Pipes are then laid on from this to all is terse, for there is sure to be a need for everything, and a parts of the town, and in these the water will rise to an eleva- place for everything, in the wide universe of God. tion nearly equal to that of the reservoir. The small difference Young women ought to be early educated in the economy of in height arises from the friction of the water in the pipes. a wise management, for such men as Soyer have clearly shown Instead of a reservoir the water is sometimes forced into a us that the most nutritious and delicate parts of fish, flesh, lofty pipe open at the upper end, and from this it flows to all and fowl are positively cast aside and despised; whilst in parts, the principle being exactly the same. In the same some households, to be liberal means to be wickedly wasteful way a fountain acts, and any one with a little mechanical and carelessly prodigal. Plentifulness is best ensured by : ingenuity can easily fit one up for himself. A reservoir has to clever economy, and not only that, but quality is procured by be provided at a height exceeding that to which the water is re- it as well as quantity. quired to rise, and a pipe is brought down from this to the jet. Young men should be taught to be economical. Who does

Springs and artesian wells depend on this same principle. not know two such in positions where their means are about In mountainous and elevated districts there is always a larger equal, where, on the one hand, there are music, books, and fall of rain, because the hills condense the clouds. This rain nameless elegances, with a little in hand beside; whilst in the soaks in through crevices of the rocks, till it finds its way to other case there is an insufficiency even of clothes and comforts, some large cavity. Many different crevices often lead thus to and a constant“ miserabile" in the manner, as though it were & one large chamber, and the water being unable to find any other hard lot indeed ? escape, rises from this to the surface, forming a spring.

Timer-spare time-economically used produces wonders. In some places all the upper strata of the soil are easily Thuse who could only attend evening classes have by their permeated by the rain, but at a greater depth there exists one appreciation of advantages within reach distanced in the race through which it cannot pass. It accordingly accumulates others who have had the whole day for mental toil. Who bas there, and if a hole be bored in the ground down to this level, not known some who, with only a few pounds for their summer the water will frequently rise to the surface and form an holiday, have managed to see the cathedral of Milan, and enjoyed artesian well. One of these near Paris is bored to a depth of much of the pleasure of a Continental tour? Careful management 1,800 feet, and the water in it rises with such force that in a must, of course, form part of most persons' lives. We are not vertical tube it would rise over 100 feet. It is said to be capable born into positions where we can gain the good we would obtain of supplying over 14,000,000 gallons per day.

---apart from sweat of brain--nor would it be well for us that EXAMPLES.

we should. Wise persons have to weigh and ponder matters,

and turn them round and round in their minds, as ladies turn 1. In an hydraulic press the diameter of the small piston is three-material in their hands to see how it will best cut out two garquarters of an inch, and that of the large one 9 inches. The lever is ments instead of one. Sometimes, indeed, the expression is 2 feet long, and the piston is attached 4 inches from the end. power must I apply to compress any substance with a force of heard, “How I dislike managing kind of people!" but this 20 tons !

means, for the most part, “I dislike bother, and trouble, and 2. What is the pressure on the sides and what on the bottom of a thought.” Let alone management altogether, and see what vessel 10 feet by 6, filled with water to a depth of 4 feet 6 inches ? most households and what most lives would come to. Those 3. A canal is 9 feet wide, and the water rises against a lock-gate to who dislike economy are in the end as cruel as they are careless

: the height of 12 feet 6 inches. Required the pressure on the gate. 4. Two pistons are fitted into a vessel. One has an area of 1 squaro and to think for them because they have not liked the worry of

other people have to discharge obligations they have incurred, inches, the other is 7 inches in diameter. What force must be exerted thinking for themselves. on the small one to produce a pressure of 380 pounds on the other ? circle is 34th times the square of the radius.)

Economy applies to health as well as to other things. It is feet deep, but the bank slopes so that the length of ration and care. A may do almost double the work of B in one

not wise to exhaust the brain force, but to rise it with considethe bottom is 6 feet. What pressure does a miten yeat ; but then all the next year A may be knocked olende k 12 yards long sustain P Bon a surface 3 inches long and 2 inches wide, nervous, and unable to work at all. Surely there must be great

sel of water, is 3 pounds. If it be sunk 3 feet deeper, want of economy in that. Here judgment and conscience must eesure be?

step in, that we may be led to do not only what we can, but

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