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indication that the law of gravitation was imposed upon this vapour, and it began to revolve round its centre of gravity, thus collecting itself into a fire-cloud, whose outmost edge stretched beyond the orbit of our most distant planet. A moment's thought will decide that the shape it would take would be that of a watch, providing that the edges were somewhat thinner. As this fire-cloud revolved in space, which is devoid of heat, it would rapidly cool. Obedient to the great law, as it cooled it would contract and become more dense, until its outward edge had reached so low a temperature that it could no longer remain in its vapour condition, when it would condense into a liquid.

The globe of red-hot matter thus produced has since lost all its heat, and forms the furthest planet of our system. So one after another the different planets condensed from the vapoury mass. As might be expected, they did so at intervals, regulated by a law, named, after its enunciator, "Bode's law." There are several points in our system which support this theory. The planets and their moons all move in the same direction. Their orbits are comprised in a narrow belt, which represents the thickness of the cloud. The exterior planets are light, and have many moonsboth which peculiarities are accounted for by the fact that the cloud would be denser near its centre, and gradually become more rare towards its outward edge, in the region where these planets condensed. There yet remains a further confirmation: the existence of Saturn's ring and the asteroids. It is well known that matter in rotation, if it be sufficiently pliable, will assume one of two shapes-either a sphere or a ring. The sphere will not be perfect, but will flatten at its poles and bulge out at its equator in proportion to the rapidity of its motion and the slight cohesion of its matter. The exterior planets are so elliptical in their shape that, looking at them through a telescope, the eye is at once struck with the fact.

The earth's equatorial diameter is twenty-six miles longer than its polar. It has been suggested that this shape may be due to the denudation of the poles by the continued evaporation of water in the regions of the tropics and its condensation as rain at the polar regions. By this means a thickness of thirteen miles was gradually transported from the pales, and deposited at the equator. But if this were the case, the earth would still possess a spherical nucleus. This, however, is disproved by certain astronomical considerations concerning the motion of the moon. Hence, the earth must be elliptical from its centrethat is, its shape is due to the action of its rotation when its mass was pliable.

The ring is the only other shape which fluid in revolution can assume to be in equilibrium; but it is remarkable that if a ring of oil which collects round a wire shape, immersed in a spirit of the same specific gravity as the oil, be made to revolve by turning the wire, when a certain speed is attained the ring suddenly breaks up into innumerable globules.

The existence of the ring of Saturn proves that that planet must once have been in a fluid condition. The asteroids seem to have been a ring of much larger dimensions, which, as in the instance quoted, broke up into many small planets. The view with which they used to be regarded-namely, that they were fragments of a planet which some internal convulsion had shattered-is now abandoned; for it can be proved that in this case the fragments must periodically return to the point from which they were hurled, which is not the case.

In the lapse of untold ages the various members of our system condensed from this vapour-cloud, and in process of time cooled down, until, losing their heat, they ceased to be luminous, and assumed the appearance with which we are familiar.

The sun is the remnant of this cloud, which was the result of the Great Being's first command, and no doubt the condensation and contraction are still going on.

But to return to our earth. After our globe had assumed the liquid condition, the process of cooling would still proceed, and the consequent contraction. The result of this would be that the vast ball of molten matter would be covered with a solid crust or skin. This crust, owing to the greater contraction of liquids than solids, would wrinkle, and, seeing the earth possessed a uniform motion, the wrinkles would take a uniform direction: this direction was from north to south. Whether water was existing in the atmosphere which enveloped the earth, as highly rarefied steam or as its constituent gases, oxygen and hydrogen, in an uncombined state, is a matter of little moment.

For many ages the surface of the earth was too hot to permit water to rest upon it; but when the cooling had sufficiently proceeded to allow of this, then that vast quantity of fluid which is the blood of the geological life of the world covered the surface of hard bare rock from pole to pole. But for long ere this was effected, the water, in a state of condensed vapour, which forms clouds, must have enwrapped the earth, and the operation ascribed to the second period of creation was the making of a firmament which should divide the waters which were above the earth--the clouds-from the waters which were on the surface: meaning to say that the cooling had sufficiently proceeded to allow the water to remain on the surface, and clouds to form.

With the dawn of the third era began the operation of a force which still exists, and to which we shall frequently have to allude: the heaving up, gradual and slow, of the northern hemisphere, and the consequent draining off of the waters towards the southern pole. The ridges, or the crests of the wrinkles, which had a generally northern direction, being elevated at their northern extremity, would form continents of a triangular shape, the point of the triangle tending southwards. This ap pearance is still perpetuated in North and South America, Africa, India, etc. A glance at the map of the world will afford many confirmations of this theory; making allowance for the repeated elevations and immersions of the continents, which would necessarily cause some alteration in their shapes. This theory bears out the assertion of the sacred record, that the sun was not made until the fourth day-that is, Mercury and Venus were not until then separated from the mass, and that luminary which we call the sun produced as he now appears to us.

From this time the varions forces which are still existing date the commencement of their operations. The tides, the ocean currents, the rivers, the streams, the rain, the atmosphere, all began their action on the Primary rocks, wearing them down, and redistributing their particles in homogeneous order along the ocean bed; here forming stratified rocks which imbedded the organic remains of that life which the Author of all life had so abundantly shed upon the now habitable earth. Whether, in after years, new facts discovered will cause another theory to supersede this, remains to be seen. As yet, this is the only supposition at all tenable. And now, leaving theory, it is our duty to describe in turn these different agents, to notice their present action, and to discover traces of their handiwork in the rocky pages of Nature's book.

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Find the interest upon :1. £1456 10s. Od. 2. 1000 0 0 3. 1698 14 8

4.

1476 8

6

5.

847 12 6

6.

987 18 9 7. 7597 10 8

for 131 days at 5 per cent.
for 201 days at 6 per cent.

for 189 days at 5 per cent.
for 20 days at 2 per cent.

from July 8 to Dec. 26, at 5 per cent.
from April 21 to Sept. 24, at 5 per cent.
from May 6 to Aug. 21, at 5 per cent.
COMPOUND INTEREST.

10. Where compound interest is reckoned, at the end of one year the interest is added to the principal. This amount becomes the principal for the second year, and the interest upon it for the second year must be calculated and then added to its principal, and so on. The difference between the final amount at the end of a number of years, and the original principal, is the compound interest.

EXAMPLE. To find the compound interest for 3 years on 2100 at 5 per cent.

At the end of the 1st year the amount is
The interest of this for the 2nd year

is

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At the end of the 2nd year the amount is The interest on this for the 3rd year is.

£105 0 0

5 5 0

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At the end of the 3rd year the amount is £115 15 3 Hence the compound interest gained in 3 years is £15 15s. 3d. In finding the compound interest upon any sum, this is the process which must be followed. It will therefore readily be seen that, when the number of years is large, and the principal and rate per cent. complicated, the operation will be very laborious. questions of compound interest are very much facilitated by the use of Logarithms, of which, however, we cannot treat here. Tables of the compound interest upon £1, at different rates per cent., and for different numbers of years, are constructed for practical use.

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2. Find the compound interest upon £555 10s. for 2 years at 4 per cent.

3. Find the difference between the simple and the compound interest upon £250 for 4 years at 6 per cent.

4. Find the difference between the simple and the compound interest upcn £365 4s. 81d. for 3 years at 4 per cent.

5. Find the compound interest upon £250 for 3 years at 23 per cent.

6. Find the compound interest upon £1040 for 3 years at 4 per

cent.

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PRESSURE-SAFETY VALVE-SOLIDS IMMERSED IN
LIQUIDS-SPECIFIC GRAVITY.

WE saw in our last lesson that the pressure in any liquid de-
pends upon the area of the surface and the depth. It is
manifest, however, that this pressure must vary with the den-
sity of the liquid, and it is found to be in direct proportion to
it. The apparatus represented in Fig. 10 supplies us with a
proof of this. A glass tube is bent into the shape of a U,
except that one limb is shorter than the other. If now we take
two liquids of different densities which will not mix, and pour
one into each limb, we shall find that the level will not be the
same in each, as it would were both filled with the same
liquid. Suppose, for instance, that mercury is poured into the
bend of the tube till it rises a little way in each limb. Now
pour water into в until it stands 13 inches above the surface of
the mercury, we shall find that then the level of the mercury in A
will be only 1 inch higher than in B. The 13 inches of water arc,
then, balanced by the 1 inch of mercury. If a layer, P O (Fig. 10),
of the mercury be supposed to become solid,
the pressure on each side of it must be equal,
since the fluid is at rest. Now the pressure
on the side towards B is equal to the weight of
the mercury on that side, and of 13 inches of
water, while that on the other side is equal
to the same amount of mercury, and a column
1 inch high in addition.

If the column of mercury, instead of being 1 inch high, were made as long as that of the water, or 13 inches, the pressure would be 13 times as great.

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We see, then, that the pressure on any body immersed in mercury is 13 times as great as on the same body immersed to the same depth in water. But the density of mercury is 13; the pressure, then, varies as the density. Hence, when two different liquids are placed in vessels communicating with each other, the heights at which they stand will be in inverse proportion to their densities.

We have now seen the most important facts concerning the pressure of liquids; but before passing on, we may just notice the construction of the safety-valve, which involves some of these principles. In an hydraulic press, the boiler of an engine, and other similar machines, there is a danger of the pressure be coming greater than the strength of the materials can overcome, in which case the cylinder will burst. To guard as much as possible against this, a safety-valve is introduced, the object of which is to relieve or remove the pressure when it is becoming dangerous.

In a convenient part of the surface which is exposed to the

C

pressure, a conical hole (A, Fig. 11) is drilled, and a valve or plug is made to fit accurately into it. This plug is fixed to a lever, c D, which turns on a hinge at c, and at the other extremity carries a weight, w. This weight can be fixed at any part of the lever, and thus the pressure exerted by it can be altered; it is usually so adjusted that, before the pressure inside the boiler begins to be dangerous, it overcomes the weight, and, opening the valve, relieves the pressure by allowing the steam to escape. Suppose, for instance, that a safety-valve has to be fitted to a boiler so as to limit the pressure to 40 lb. per square inch. Let the plug, A, have an area of half a square inch, and be attached to the lever at a distance of 2 inches from the fulcrum, also let the weight be 2 lb. Since the plug has an area of half a square inch, it must yield when a force of 20 lb. is applied to it, and must therefore be pressed down with this force. The weight is one-eighth of this, and hence it must act at a leverage 8 times as great-that is, it must be fixed 16 inches from c. If, then, the weight be adjusted thus, the boiler is perfectly safe, for when the pressure exceeds 40 lb. to the inch, the valve will open and allow some of the steam to escape. These valves are sometimes made with a spiral spring instead of a lever, but they act in the same way. In practice it is common to have two; one is so placed that it cannot be touched or altered, and this is adjusted to the greatest pressure that can with safety be applied; the other is under the control of the engineer, who adjusts it according to the pressure he requires. The sides of the valve are always made to slope considerably, as otherwise it might become rusted in, and thus cause an explosion.

Fig. 11.

We now pass on to notice the effects produced on solids by their immersion in liquid. Of course, we only deal now with the mechanical or physical effects, and therefore speak only of substances that are insoluble in water. Some bodies are dissolved, and others are chemically altered by immersion in liquid; but it is the province of chemistry to examine these changes. The main effects produced by the immersion of a solid in a liquid are the following:

1. It displaces a volume of fluid equal in bulk to itself. 2. It is buoyed up with a force exactly equal to the weight of an equal bulk of the fluid, and therefore loses a portion of its weight equal to this.

3. The upward pressure of the surrounding liquid acts vertically through the centre of gravity of the displaced liquid. If we dip our hands into a heavy liquid we feel this buoyancy; or if, when bathing, we lift a large stone, we shall find that it is easier to carry it when it is under water than when above. A more conclusive proof is to suspend a heavy body from a spring balance, and having observed the weight, dip the body into water and observe again how much it weighs. We shall find that its weight is apparently less than it was. When a solid is thus immersed, it is clear that it must displace a quantity of water equal in bulk to itself. Two substances cannot occupy the same space at the same time-the solid, therefore, takes the place of an equal volume of the liquid; and if before immersion we completely fill the vessel with water, and carefully catch all that runs over when the solid is dipped into it, we shall have an experimental proof of the fact. In this way the bulk of a solid of irregular shape may easily be ascertained. We have only to plunge it into a vessel brim-full of water and measure the amount that runs over, and this will give us the bulk of the solid.

Now the loss of weight in the solid is exactly equal to that of this bulk of water. Let it have the shape of a (Fig. 12), and let a portion of the water in the vessel having the same bulk and shape be supposed to become solid; it will remain in equilibrium, the forces acting upon it being its own weight acting downwards through its centre of gravity, and the upward pressure of the surrounding water which is exactly equal and opposite to this. Now let the solid take the place of this, and it will be buoyed up to exactly the same extent, since no change is made in the water rround. The strain on the cord will be equal to the weight of A, less the weight of the equal bulk of liquid. A, therefore, loses this portion of its weight. Just the same reasoning will apply if the solid, instead of being wholly immersed, floats on the surface. The weight of the water it displaces will be exactly

equal to its own. If, then, it weighs only half as much as an equal bulk of water, it will only be immersed to half its depth. We thus see that a body will float, remain suspended, or sink, according as its weight is less, equal to, or greater than that of an equal bulk of water. Thus any solid, however heavy, may be made to float, provided it be flattened out and shaped so as to displace a bulk of water weighing more than itself. In this way, though iron is seven times heavier than water, ships are made of it, which, even when loaded with a heavy cargo, are perfectly safe.

The human body, in its ordinary condition, is lighter than water, and hence will float with a small portion above the surface. The art of swimming, therefore, is to keep the body in such a position that the nose and mouth may be above, so that breathing may not be interrupted. Fear, however, causes the chest to be contracted, and thus a less bulk of water is displaced, and the body sinks deeper. The same principle accounts for the fact which every swimmer must have noticed, that it is easier to swim in salt water than in fresh. A volume of sea water weighs more than an equal volume of fresh; hence a smaller bulk is displaced by his body, and accordingly he is lifted higher out of it, and has a smaller quantity to displace as he moves through it. In the same way a ship is always found to draw less water in the sea than in a river; hence, a vessel in a river may be loaded till she is immersed too far below the water-line to be able to stand rough weather, but on reaching the sea she rises sometimes three or four inches.

We may state, then, generally that a body in any liquid loses as much of its weight as is equal to that of the liquid it displaces. There is one simple experiment which furnishes an elegant proof of this. Let a cylinder of brass be procured, and also a case which it fits into and exactly fills. Place the cylinder and case in one pan of a pair of scales and carefully balance it. Now take the cylinder from the case, and by a fine thread or hair suspend it under the pan, and so arrange the apparatus that it may dip into a jar of water. The scale will at once rise, showing that the cylinder has lost weight by immersion; but if we pour water into the case till it is filled, we shall find that the scales balance as at first. We have thus a conclusive proof of the proposition, the water in the case being clearly exactly equal in bulk to the cylinder.

A

This principle is said to have been discovered by Archimedes in the following manner:-Hiero, the King of Syracuse, had some gold which he wished made into a crown; so, having weighed it, he handed it to a jeweller of the day for that purpose. When it was returned he found the weight was correct, but had a suspicion that some of the gold had been kept back and its place supplied by baser metal. He accordingly requested Archimedes to try and discover whether or not it was so. For a long time he puzzled his brain, trying to devise some plan for solving the problem. At last, when taking a bath, he noticed that his body displaced a bulk of the water, and was buoyed up by its pressure. From this the idea struck him, and he rushed out exclaiming, “I have found it! I have found it!"

SPECIFIC GRAVITY.

Fig. 12.

The principle we have been examining is of great use in the determination of the density, or "specific gravity," as it is termed, of different bodies.

It is a well-known fact that different substances contain different quantities of matter in the same bulk. If we take a number of 1 inch cubes of various bodies, as, for example, cork, oak, iron, stone, etc., and carefully weigh them, we shall find that they differ very greatly in their weight. The cork will weigh about 60 grains, the oak about 190, while the iron will weigh nearly 4 ounces. But though there is this difference between different substances, we shall find that a cubic inch of any one substance always weighs nearly the same. If, then, we could procure equal blocks of all substances, and note their weights, we could form a table of densities. The advantages of this would be very great. Sometimes we have a large block of known size, and we wish to know the weight, or we may want to know how much space a given weight of any substance would occupy, and all such questions could be solved from this table. It is, however, impossible to procure such

blocks of many substances on account of their shape or physical properties, and many other bodies are too small or too valuable. We cannot, then, compare their densities in this way, but we may take some substance as a standard, and compare the weights of all others with this.

Now any substance might be chosen for this purpose, the main requisites being that it shall be easily procurable in a state of purity, and easy of manipulation. Water has been chosen as this standard, and is found to answer well. When, therefore, we speak of the specific gravity of any body, we mean this-the proportion which exists between its weight and that of an equal bulk of distilled water at a temperature of 60*.

The reason why we thus fix on a certain temperature is that water expands by heat, and therefore a cubic inch of hot water weighs less than an equal bulk of cold. The temperature of 60° is chosen merely as a matter of convenience, that being about the average, and therefore involving less trouble. When, then, we say the specific gravity of mercury is 13:6, we mean that any amount of mercury weighs 13'6 times as much as an equal bulk of distilled water at 60°. Now, as we have seen, the weight of a cubic inch of distilled water is 252-5 grains; a cubic inch of mercury therefore weighs 2525 grains x 13'6, or 3,434 grains, which is nearly 8 oz. We can in this way, if we know the specific gravity of a body, tell the weight of any bulk of it. Questions like the following frequently occur, and can thus be solved :-What is the weight of a block of coal 3 feet x 5 x 4, the specific gravity of coal being 1.270 ?

Since the specific gravity of the coal is 1.270, the weight of a cubic foot is 1.270 times that of an equal bulk of water. But a cubic foot of water weighs about 1,000 oz.; a cubic foot of coal must then weigh 1,270 ounces. Now the total bulk of the coal is 3 x 5 X 4 = 60 cubic feet. Its weight, therefore, is 60 x 1,270 ounces=76,200 ounces, or 42 cwt. 2 qr. 21 lb. Again, strong oil of vitriol has a specific gravity of 1850; how much will 6 lb. measure? A fluid ounce of water, it must be remembered, weighs one ounce avoirdupois; 6 lb. of water, then, would measure 96 oz.: but since oil of vitriol is heavier than it, in the proportion of 1,850 to 1,000, it will measure proportionately less. Hence the following proportion will give us the bulk:

As 1,850: 1,000 :: 96: the required volume.

On working this out, we shall find that the vitriol will measure 51.89 oz., or nearly 34 ordinary pints.

We see thus the importance of knowing the specific gravity of any substance, and there are several modes of ascertaining it, one or other of which is more applicable according to the circumstances of the case. If, however, we bear in mind exactly what it is we wish to know, we shall find little difficulty in remembering which way to proceed.

and, as before, we first find the weight of water required to fill it to a certain mark, and then the weight of the liquid we are operating upon.

The details of an actual experiment will make this clearer. A sample of nitric acid was taken, of which it was desired to ascertain the specific gravity. The small bottle was first put in the scales and found to weigh 80 grains. On being filled with the acid it weighed 159 grains. The acid was next emptied out, the bottle rinsed, and filled to the same height with water, the weight being then 136 grains.

B

Now, since the bottle weighed 80 grains, we subtract this amount from its weight when filled with the different liquids, and thus see Fig. 13. that the water in the bottle weighed 56 grains, while the weight of the same bulk of acid was 79 grains. We have, then, the following equation by which we can determine the specific gravity of the liquid:

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ANSWERS TO EXAMPLES IN LESSON II. (Vol. II, page 398).

1. Since the areas of the pistons are to one another in the proportion of the squares of their diameters, the larger has 144 times the area of the smaller. There is also a gain of 6 by the lever. Thus the advantage gained is 144 × 6 or 864. If we divide 20 tons by this, we find the required pressure is 51.85 pounds.

2. The area of the sides is together 144 feet, and the mean depth 2 feet. The total pressure on them is thus equal to the weight of This is nearly 324,000 ounces, or 144x2 or 324 cubic feet of water.

9 tons and 90 pounds. The pressure on the bottom is 6 × 10 × 44 × 1,000 ounces, or 7 tons 10 cwt. 2 qrs. 19 lb.

3. Rather more than 193 tous.

4. The area of the large piston is 38 square inches. The required pressure is therefore nearly 40 pounds.

5. Just over 15 tons.

6. The additional pressure will be that of a column of water having an area of 6 square inches, and a height of 3 feet. This will be of a cubic foot, and therefore weigh 7 lb. 13 oz. The total pressure is

LESSONS IN GREEK.-XIV.

We will consider, first, how to proceed in the case of a liquid. Procure a thin glass flask (Fig. 13, A) provided with an accurately fitting stopper. Instead, however, of this being solid, let it be drawn out, as shown at B, into a long tubular neck, so that when it is put in its place any excess of liquid may escape through it. The flask is best made of such a size as to hold 1,000 grains up to the mark o in the neck. Now procure a small piece of metal, and file or grind it till it exactly balances the flask and stopper therefore 10 lb. 13 oz. when empty. If the flask, filled with distilled water to the level o, be put in one pan of a balance and the counterpoise or weight in the other, we must add just 1,000 grains to balance the water. Empty this out, and fill it with the liquid whose specific gravity we want to know-say, for instance, the strongest alcohol-and weigh again; we shall now find that only 792 grains are required to balance it. The weight, then, of any volume of alcohol is to that of an equal bulk of water in the proportion of 792 to 1,000; or, in other words, the specific gravity of the alcohol is 792. The reason why we chose a flask containing 1,000 grains is now clear, for all trouble in calculation is thus avoided. We have only to take the weight of the liquid in grains, and point off three figures as decimals, and we have the specific gravity.

Thus, if we fill the bottle with sea water, we shall find it will weigh 1,028 grains; the specific gravity is therefore 1·028. Sometimes, however, it is difficult or costly to procure a sufficient quantity of the liquid to fill such a large flask. We then use a much smaller one, usually made out of a glass tube,

REVIEW OF THE THREE DECLENSIONS. WITH the nouns of the first and second declension, the student, if he has thoroughly mastered the foregoing lessons, will find no difficulty in any attempt he may make to construe classical Greek. It is somewhat different with nouns of the third declension, the discovery of the nominative of which is necessary in order to consult a Greek lexicon with ease and effect. I therefore subjoin the following, which will enable him from the genitive case to find the nominative; in which form substantives and adjectives appear in dictionaries. I give the genitive, because the genitive is, as it were, the key to the remaining oblique cases. Thus, if you meet with avopa, you know the genitive must have two of these letters, namely, op; if you meet with xeuwves, you know the genitive will have the letters χειμων ; if you meet with μελανες, you know the genitive will have the letters μeλav. Now, from the genitive you may get

to the nominative, and you may do so by the aid of what has already been said. But for this you must bear in mind that tho v in μελαν, though belonging to the stem, does not appear in the nominative. In the following table, however, you will find that a genitive having an v, as in -avos, comes from a noun in -as ; μελας, therefore, is the word which you have to look for in the lexicon, and μελας you find to mean black. Thus, you see, if the genitive be given, the word is easily ascertained :Nominative Ending.

Genitive Ending. -δος, -θος, τος

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I wish you, with the aid of this table, to review the ground over which we have gone. With it you should possess the utmost familiarity before you pass on to the next topic. In order to assist you, and at once to ground you in what you have learnt, and to enlarge your acquirements, I subjoin exercises bearing on the three declensions. These exercises are taken from the best Greek authors, and from the sacred Scriptures. When you have mastered them, you will feel that already you have made some progress.

I premise a few syntactical remarks. In Greek, as in Latin, adjectives, adjective pronouns, and participles agree with their nouns in gender, number, and case. That is, if the noun be in the accusative singular, in the accusative singular must the adjective, etc., be. If the noun be in the genitive plural, the adjective must be in the genitive plural. If the noun be of the neuter gender, put the adjective in the neuter gender; and so in all other cases, the adjective, the adjective pronoun, and the participle, when they agree in sense, must agree also in form, and be in the same gender, number, and case. Thus we say αγαθος ανηρ, a good man; but if we use γυνη instead of ανηρ, we must change αγαθος into αγαθη. Also we write ανδρα αγαθον | θαυμάζω, I admire a good man, but γυναικα αγαθην θαυμάζω, Ι admire a good woman-where αγαθος becomes αγαθον to agree with ανδρα, and αγαθην to agree with γυναικα. Compare the declensions of adjectives and nouns combined in the fourth and sixth lessons.

As a general rule, a transitive verb, or a verb which has an object after it, has that object in the accusative case, as in the sentence just given—ανδρα αγαθον θαυμαζω. Many verbs, how ever, put their objects in some other case; some require the genitive, and some the dative. Examples have already appeared. When two nouns come together in a state of dependence, the dependent noun is put in the genitive case: for example, 'O Αλεξανδρος του Φιλίππου ην υἱος, Alexander was the son of Philip; where Φιλιππου is in the genitive case, because it is in sense dependent on vios.

When two verbs come together in a state of dependence, the dependent verb is put in the infinitive mood: for example, βουλομαι ὕδωρ πίνειν, I wish to drink water; where πινειν is governed in the infinitive mood by βουλομαι, the former being in sense dependent on the latter.

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RECAPITULATORY EXERCISES SELECTED FROM THE GREEK CLASSIC AUTHORS.

δ

8.

1. Μια χελιδων εαρ ου ποιεί. 2. Παντα ὁ χρόνος προς φως αγει. 3. Πελοπι υἱοι ησαν Ατρευς και Θυέστης. 4. Πολλα ανθρωποις παρ' ελπίδα γιγνεται. 5. Γυναιξί κόσμος ὁ τροπος (understand εστιν ου τα χρυσία. 6. Οἱ τεττιγες ευφωνοι λεγονται είναι. 7. Μυρμηκων και μελισσων βιος πολυπονος εστι. Γιγνώσκει φωρ τον φωρα και λυκος λυκον. 9. Ου κτησις αλλ' ή χρησις των βιβλιων οργανον της παιδειας εστιν. 10. Η μεν φυσις ανευ μαθησεως τυφλον, ἡ δε μαθησις διχα φύσεως ελλιπες. 11. Ο χρόνος τῳ γηρᾳ προστίθει την επιστημην. 12. Πολλαι ησαν αἱ της βουκερω Ιοῦς πλαναι. 13. Ανηρ ανδρα και πολις πολιν σωζει. 14. Επαμινώνδας ως αληθώς εν ανδρασιν ανηρ ην. 15. Γερων γεροντι γλωσσαν ήδιστην έχει, παις παιδί, και γυναικι προσφορον γυνη. 16. Παντες οἱ των αριστων Περσών παίδες εν ταις βασιλεως θυραις παιδεύονται. 17. Ξίφος τιτρώσκει σωμα, τον δε νουν λογος. 18. Η φρόνησις μεγιστον εστιν αγαθον. 19. Πολεως ψυχη οἱ νομοι. 20. Ἡ τυραννις αδικίας μητηρ εστιν. 21. Ο δειλος της πατρίδος προδοτης εστιν. 22. Οἱ αγαθοι άνδρες θεων εικονες εισιν. 23. Οἱ Νομάδες των Λιβυων ου ταις ἡμεραις, αλλα ταις νυκτεσι αριθμοῦσιν. 24. Χαλεπον εστι λεγειν προς γαστέρα, ωτα ουκ έχουσαν. 25. Ήφαιστος τω ποδε χωλος ην. 26. Η Μήδεια γράφεται τω παιδε δεινον ὑποβλέπουσα. 27. Ήθους βασανος εστιν ανθρωποις χρόνος. 28. Οι οφεις τον ιον εν τοις οδουσιν εχουσιν. 29. Ο Παρνασσος μεγα και συσκιον όρος εστιν. 30. Εν Βοιωτια δυο εστιν επισημα όρη, το μεν Ελικων καλούμενον, ετερον δε Κιθαιρων. 31. Ο Νείλος έχει παντοια γενη ιχθυών. 32. Τιμα τους γονεῖς. 33. Αναχαρσις την αμπελον είπε τρεις φερειν βοτρυς· τον πρωτον, ηδονης· τον δεύτερον, μεθης· τον τρίτον, αηδίας. 34. Πονος ευκλειας πατηρ (understand εστιν). 35. Ωκεανου και Τηθύος παις ην Ιναχος. 36. Οἱ τεττιγες σιτούνται την δροσον. 37. Κλεανθης εφη τους απαιδευτους μονῃ τῇ μορφή των θηρίων διαφερειν. 38. Ανάχαρσις ονειδιζόμενος ότι Σκύθης ην, είπε, τῳ γενει αλλ' ου τῷ τρόπῳ. 39. Κολάζονται εν άδου παντες οἱ κακοι, βασιλεις, δουλοι, σατράπαι, πενητες, πλουσιοι, πτωχοι. 40. Αἱ Φορκου θυγατέρες γραίαι ησαν εκ γενετής. 41. Ζηνων εφη, δειν τας πολεις κοσμειν ουκ αναθήμασιν, αλλα ταις των οικουντων αρεταις.

shall take each sentence in the order in which it stands, because In giving the vocabulary of these recapitulatory exercises, I the learner will here need more aid than he has hitherto required

or received.

VOCABULARY TO THE EXERCISES FROM THE CLASSICS. 1. Μια, one, from the numeral adjective eis, μια, έν, one, of the fem. gen. to agree with χελιδών, a noun, 3rd dec. nom. sing., fem. χελιδων, χελιδονος, a swallow.

2. This sentence contains nothing that the student ought not to know. I therefore leave him to the knowledge he has, or may have, already attained, and so in future shall I do without giving notice thereof.

3. Πελοπι, from Πελοψ, Πέλοπος, & proper name, governed in the dative case by ησαν; to Pelops there were, that is, Pelops had; Ατρευς (gen. -εως), Atreus; Θυέστης (gen. ov), Thyestes. Observe that the English y represents the Greek v.

4. Παρ' for παρα, against, παρ' ελπίδα, contrary to their expec tations, ελπίδα, acc. sing., from ή ελπις (gen. ελπίδος), hope. Why has tho plural adjective πολλα the verb in the singular 5. Τροπος, -ου, δ, a turn, disposition; χρυσία, neut. pl., from χρυσιον, a diminutive of χρυσος, gold, and so denoting golden ornaments, jewels.

6. Τεττιγες, grasshoppers, from ὁ τεττιξ (gen. τεττίγος); ευφωνοι, pleasing in sound, nom. pl., from εύφωνος (εν and φωνη, a voice), an adjective of two terminations ; λεγονται, are said, the third person plural, passive voice, present tense, from λεγω, I say; it governs είναι, to be, in the infinitive mood.

7. Μυρμήκων, gen. pl., governed by βιος, from ὁ μυρμηξ, μυρμηκος, an ant; μελίσσων, gen. pl. governed by βιος, from μέλισσα, ης, ή, a bee; πολυπονος, -ον (from πολυς and πονος), laborious.

8. Γιγνώσκει (from γιγνωσκω, I know), indicative mood, active voice, third person singular, agreeing with its subject or nominative φωρ; φωρ, φωρος, δ, a thief, λύκος, -ου, δ, a wolf.

9. Χρησις, εως, ή, use ; οργανον, -ου, το, a means, our organ. 10. Ανεν, without; τυφλον, from τυφλος, -η, -ov, blind; the adjective is in the neuter gender, denoting disparagement, a blind thing; διχα, separate from; ελλιπες, from ελλιπης, -ες, defective (from λείπω, I leave).

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