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momentum it had acquired is thus soon dispelled. If all such We now pass on to the third law of motion, which was stated counteracting causes could be removed, the body would move on by Newton as follows :-Reaction is always equal and contrary for ever. This cannot, of course, be proved directly by experi- to action, or the mutual actions of two bodies upon each other ment, but we can easily assure ourselves of its truth, for, in are always equal and in opposite directions. When a carriage proportion as we remove these obstructions, the motion con- is drawn by horses, they are pulled back with the same force as tinues for a longer period. If, instead of rolling the stone along the carriage is drawn forward; so, if a boat in a stream be the ground, we send it on smooth pavement, the motion will pushed off from another, the quantity of motion produced in continue to a much greater distance; and if we try the experi- each is the same. If both be of the same weight they will move ment on a good surface of ice, it will move farther still, the with the same velocity; but if one be heavier, its motion will be simple reason being that the force of friction which before so much less than that of the other. We see, thus, that motion overcame its motion has been greatly removed. In a similar is never lost, it always produces motion in other things; but as way we can carefully construct a pendulum so as to swing with this is shared among all bodies in proportion to their mass, it as little friction as possible, and having started it from a given soon becomes so small as to be unnoticed. point in the arc, note how long it takes to settle to rest. Now Now if we consider the pressure on a body to be the action, remove it to the receiver of an air-pump, exhaust the air, and the quantity of motion produced is the reaction, and this law set it vibrating as before, it will be found that the motion will asserts that these are equal. But the quantity of motion is continue for a much greater length of time, the resistance of measured by the product of the mass and the velocity, that is, the air being in a great degree removed.
by the momentum generated. From experiments like these we can ascertain the truth of the The momentum produced is therefore proportional to the preslaw, and it is important to bear it in mind, since the neglect of sure. Hence the law is frequently stated thus :—When presit has often led to great mistakes.
sure produces motion in a body, the momentum generated is Force, then, is not required to maintain motion, but only to proportional to the pressure. Momentum, then, is the measure produce or alter it, either by increasing or diminishing its speed, of moving force, as velocity is of accelerating force. From this or by changing its direction.
we find a way of comparing these two. The latter is measured We now turn to the second law of motion, which may be by the velocity, irrespective of the mass, and as the pressure, stated as follows :—When any number of forces act on a which is the moving force, imparts the velocity to the body, it particle, each produces its full effect in producing or altering is equal to the mass multiplied by this velocity. That is motion, exactly as it would if it acted singly on the body when moving force mass X accelerating force. Hence, if we at rest.
divide the moving force by the mass, we obtain the accelerating Of this we have many simple proofs. Let a stone be dropped force. from the mast-head of a ship, it will fall exactly at the foot of From this we can calculate the dynamical unit of force, that the mast, just as if the vessel were perfectly at rest.
is, the force required to cause the unit of mass to move one foot If gravity alone acted upon it, it would reach the deck some per second, which force we stated in our second lesson to be distance in the rear of the mast, for in the interval which it has 7.85 grains. ocoupied in falling, the vessel has been moving onwards, and the The unit of mass is one cubic inch of distilled water, and this point from which the stone fell is, when the stone reaches the weighs nearly 253 grains. deck, vertically over a place some distance behind the mast; but Now the accelerating force of gravity which produces this another force was also acting on the stone, and that was the weight is 32.2, that being, as we shall shortly see, the velocity onward motion which, like the vessel, it had acquired. This a falling body acquires in one second. But the velocity we want motion was exactly equal to that of the vessel, as both were is only 1 or als of this. Hence the unit of moving force is moving at the same rate; and each of these forces produces its full effect. The stone falls in exactly the same time as it would 253 gr. x 22 or 7-85 gr. take if the vessel were at rest; it moves througb the same The proof of the third law we must defer to the next lesson. horizontal space that it would if it were not falling; and at the end of the time occupied in falling is in the same place as if each force had acted singly during that length of time, the only
ANSWERS TO EXAMPLES IN LESSON XV. difference being that then it would have passed over two sides of 1. 60 x 10 x 70 = 42,000 units. a parallelogram, whereas now it has travelled down the diagonal.
2240 x 20 x 400
2. The work done per minute is Another good illustration of this is afforded by a boat cross
or 298,666 units.
298,666 ing a river when the stream is running down rapidly. Suppose Hence the H. P. required is which is a little over 9. the stream to be flowing in the direc
33,000 tion of the arrow. A boatman at A
3. It would raise it from a depth of 663 feet.
4. About 47 lbs. per hour. wants to cross to a point B some dis
5. About 51 days by means of a windlass, or 31 days by ascending a tance lower down; he does not, how- ladder and allowing his own weight to raise it. ever, steer directly for it, since, if he
did, the force of the stream would carry
him to some point much lower down,
LESSONS IN GREEK.-VIII. site him. If the current be so rapid that it would carry him
THE THIRD DECLENSION (continued). down from c to B in the time it takes him to row from A to c, he The adjectives which follow the nouns of the Third Declension must steer directly across to c. There will be then two forces given in the last lesson, are-1, d, j anatP, To aratop, fatheracting on the boat—his own force impelling it from a to c, and less, auntwp, auntop, motherless, the genitive ends in opos: 2, the force of the stream from c to B, and under the joint action o, in appnv, to appev, manly; gen. appevos: 3, adjectives in wv (m. of these two forces it will move from A to B in the same time and f.) and ov (n.), as ó ñ eudaluwv, to evdalpov, happy; and the that it would take him to row to c. If, now, he wants to cross comparatives in wv, ov, www,.cov. These comparatives, after again to d he must steer for some point higher up than for
dropping the suffer contraction in the accusative singular, and as B A is longer than a c, the tide will have more time to act in the nominative, accusative, and vocative plural. The vocaupon the boat and carry it down. More commonly, however, he tive is the same as the nominative neuter. rows from B towards c along the shore, where the current has less force, and then crosses as at first. But it is clear that in
Singular. either case each force produces its full effect.
Greater. In our lessons on statics we learnt the parallelogram of forces, ໖,
8,1 and found that if two forces acting on a body be represented Nom. ευδαιμων, ευδαιμον. εχθίων, εχθίον. μειζων, μειζον. . by two adjacent sides of a parallelogram, the resultant will be Gen. ευδαιμονος. .
μειζονος. . represented by the diagonal. We may now extend this principle Dat. ευδαιμονι.
μειζονι. . to velocities, thus :-If any two velocities impressed on a particle Acc. ευδαιμονα, ευδαιμον. εχθίονα, εχθίον. μειζονα, μειζον. be represented by two sides of a parallelogram, the diagonal
(μειζω). will represent the resulting motion in direction and velocity. Voc. ευδαιμον. .
and in the dative plural; also in the interposition of a before και, ή
ou of the dative plural, in order to soften the sound. The Νιλ. ενδειο», «ελεζάνα, έχθίονες, εχθίονα. μειζονες, μειζονα, word arnp (stem avep), throws away the e in all the cases of the
(εχθίους), (εχθίω). (μειζους), (μειζω). | three numbers, except the vocative singular, and for the gate εχθίονων.
of sound introduces a 8: as appears from this tabular view, εχθίοσι. μειζοσι.
Singular. Αις «διερευνας, ευδαιμονα, έχθίονας. εχθίονα. μειζονας, μειζονα. Νom.
μητηρ. θυγατηρ. ανηρ. (εχθίους). (εχθίω). (μειζους), (μειζω). | Gen.
πατρ-05. μητρ-0S. θυγατρ-ος. ανδρ-ος. Lid the Nom. Like the Nom. Like the Nom.
μητρ-ι. θυγατρ-ι. ανδρ-ι. Dual.
θυγατερ-α. ανδρ-α. Ν. Α.Ν. ευδαιμονε.
πατερ. μητερ. θυγατερ.
Plural. 6. The Nominative has the short vowel of the stem lengthened, as Nom. πατερ-€5. μητέρ-€5. θυγατερ-ts. ανδρ-€5. e into n, and o into w.
Gen. πατέρ-ων. μητέρ-ων. θυγατερ-ων. ανδρ-ων.
ανδρ-α-σι. Stems in ντ drop the τ in the nominative; as, λεων instead
Acc. . πατέρ-ας. μητέρ-ας. θυγατερ-ας. ανδρ-ας. of λεωντ. Singular.
Voc. . πατέρ-€5.
ανδρ-€5. Shepherd. Divinity. Lion. Ether (air). (orator).
Dual. Nom. ποιμήν. δαιμων. λεων. αιθηρ. ρητωρ.
N.A.V πατέρ-€. μητερ-€.
θυγατερ-€. ανδρ-€. Gen. ποιμεν-05. δαιμον-ος. λεοντ-ος. αιθερ-05. ρητορ-ος.
θυγατερ-οιν. ανδρ-οιν. Dat. . ποιμεν-ι. δαιμον-1. λεοντ-ι. αιθερ-ι. ρητορ-ι.
The word artnp, -epos, a star, which otherwise retains the e Acc. ποιμεν-α. δαιμον-α. λεοντ-α. αιθερ-α. ρητορ-α.
of the stem, belongs to this class in consequence of having its Voc. . ποιμήν. δαιμον. λεον. αιθηρ. ρητορ.
dative plural in αστρασι. Plural.
VOCABULARY. Nom. ποιμεν-ες. δαιμον-ες. λεοντ-ες. αιθερ-ες. ρητορ-€5.
Αθλον, -ου, τo, a prize Εχθαιρω, I hate. Στεργω, I love. Gen. .
αιθερ-ων. ρητορ-ων. ποιμεν-ων. δαιμον-ων, λεοντων.
gained in the pub- Περσεφονη, ης, ή,Per- Χαιρω (dative), IreDat. ποιμέ-σι. δαιμο-σι. λεου-σι. αιθερ-σι. ρητορ-σι.
sephoné (per-sef- joice at, delight in. Acc. ποιμεν-ας. δαιμον-ας. λεοντ-ας. αιθερ-ας. ρητορ-ας.
Δουλευω, I am o-ne), Proserpine. | Χαριζομαι, I show Voc. ποιμεν-fs. δαιμον-ες. λεοντες. αιθερ-€5. ρητορ-€ς.
slave, I serve. Σοφος, -η, -ον, wise. favour, gratify. Dual.
EXERCISE 23.--GREEK-ENGLISH. ποιμεν-€. δαιμον-€. λεοντ.€. αιθερ-€. ρητορ-€. G.D. ποιμεν-οιν. δαιμον-οιν. λεοντ-οιν. αιθερ-οιν. ρητορ-οιν.
1. Στεργετε τον πατερα και την μητερα. 2. Μη δουλευε τη
γαστρι. 3. Χαιρε, ω φιλε νεανια, τφ αγαθω πατρι και τη αγαθή Δαηρ, α husband's brother, makes in the vocative δαερ; Αμφίων μητρι. 4. Μη συν κακή ανδρι βουλευου. 5. Δημητρι πολλοι και (ονος) makes ω Αμφίον; also Αγαμεμνων (ονος) νοcative Αγαμεμνον, καλοι νεο ησαν. 6. Η αγαθη θυγατηρ ηδεως πειθεται τη φιλη The following in wv (ovos) in some cases drop the v and
μητρι. 7. Οι αγαθοι ανδρες θαυμαζονται. 8. Πολλακις εξ αγαθου undergo contraction : η αηδων, the nightingale, genitivo αηδονος, πατρος γιγνεται κακος υιος. 9. Εκθαιρω τον κακον ανδρα. 10. contracted into αηδούς, dative αηδοί; ή χελίδων, swallow, geni- Τοις αγαθοις ανδρασι λαμπρα δοξα έπεται. 11. Η Δημητρος tivo χελίδονος, dative χελιδοί.
θυγατηρ ην Περσεφονη. 12. Ω φιλη θυγατερ, στεργε την μητέρα. VOCABULARY. 13. Η αρετη καλον αθλον εστιν ανδρι σοφφ. 14. Οι αγαθοι υιοι
15. Οι Έλληνες Αγελη, -ης, ή, a flock, Εικα (dat.), yield; Ολβιος, -α, -ον, happy. τους πατερας και τας μητερας στεργουσιν. herd. .
της οδου, get out Σωφρων,-ον, gen.-ονος, | Δημητερα σεβονται. 16. Πειθεσθε, ω φιλοι νεανιαι, τοις πατρασι Αδικος, -ον, unjust of the way of. sound-minded. και ταις μητρασιν. 17. Χαριζου, ω φιλε πατερ, τη αγαθη θυγατρι. (α priv., and δικη, Ηγεμων, -ονος, o, a Υπερφρων, υπερφρον,
EXERCISE 24.-ENGLISH-GREEK. justice). leader, general. genitive-ovos, high
1. O young me
love your father and mother. 2. Good Ανευ (genitive), with- Θεραπευω, I honour. minded, too high. daughters obey their (the) father and mother. 3. The citizens out.
Κολαστης, -ου, ο, και minded, proud worship Ceres. 4. Persephoné follows Ceres. - 5. We admire Γερων, -οντος, o, an punisher,
(υπερ, over). the star. 6. Be not ye, 0 huntsmen, slaves to the belly. 7. old man.
Λιμην, -ενος, a har- Φρην, -ενος(pl.φρενες), A good mother loves a good daughter. 8. Ο mother and father, Δημος, -ου, δ, the bour. .
the heart, soul.
love your children. 9. The man is hated. 10. They hate the people (Lat., popu. Naww, I inhabit,dwell. Quattw, I watch,
man. 11. They obey wise men. 12. I follow Ceres. 13. Often lus). “Οδος, -ου, ή, a way. guard, keep.
bad sons arise from a good father and mother. EXERCISE 21.-GREEK-ENGLISH.
Note that the Greek article has frequently the force of su 1. Τον γεροντα θεραπευε. 2. Σεβου τους δαιμονας. 3. Οι | English possessive pronoun, when, from the nature of the Benποιμενες αγελας φυλαττουσιν. 4. Τον κακον φευγε ως κακον | tence, no mistake as to the meaning can arise. Consequently, λιμενα. 5. Ανευ δαίμονος και ανθρωπος ουκ ολβιος εστιν. 6. 'o in such cases, when you translate into English, give the posθεος εν αιθερι ναιει. 7. Πολλακις χαλεπαι μεριμναι τειρoυσι τας
sessive pronoun for the Greek article, and when you translate των ανθρωπων φρενας. 8. Eπου, ω φιλε, αγαθοις ηγεμοσιν. 9. into Greek, give the article for the possessive pronoun. Εικε, ω νεανια, τοις γερουσι της οδου. 10. Πολλακις δημος ηγεμονα εχει αδικον νούν. 11. Ο θεος κολαστης εστι των αγαν υπερφρονων.
KEY TO EXERCISES IN LESSONS IN GREEK.-VII. 12. Εχε νούν σωφρονα. 13. Ω δαιμον, παρεχε τοις γερουσι καλην
EXERCISE 15.-GREEK-ENGLISH. ευτυχιαν. 14. Οι θηρευται τους λεοντας ενεδρευουσιν.
1. Temples are built to the gods. . 2. It is not easy to walk on EXERCISE 22.--ENGLISH-GREEK.
3. We hunt hares. . 4. Androgeus was the son of Minos, 1. Good boys honour old men. 2. Old men are honoured by 5. Hares are hunted by huntsmen. 6. Pray to the merciful God. 7. good boys. 3. Sound-minded young men get out of the way of Eagles capture bares. 8. Reverence the merciful divinities. 9. Two old men. 4. Follow, O friends, a good leader. 5. We have brave receive deathless praise. 10. Pray that you may have (fied)
11. The gods are propitions to the good. 12. Pleasure good leaders. The people often follow bad leaders. 7. God lead away most people as captive. 13. The Samians support beautiful affords prosperity to the sound-minded. 8. Lions are hunted peacocks in honour of Juno. 14. The peacock has beautiful wings. by huntsmen. 9. We worship the divinity.
EXERCISE 16.-ENGLISH-GREEK. To the previous examples belong the following substantives
1. Τοις θεοις νεως κτιζεις. 2. Κτιζονται νεφ τοις θεοις. 3. Νεων των θα in ηρ-namely, ο πατηρ, the father και η μητηρ, the mother ; ή κτιζω. 4. Επι καλών βαινουσι. 5. Τους λαγως θηρευομεν. 6. οι λαγων θηρευονται, θυγατηρ, the daughter; ή γαστηρ, the belly και η Δημητηρ, Demeter 7. Οι Σαμιοι καλους ταως σεβονται. 8. Τον ελεων θεον σεβονται. 9. Ο θεος (Ceres in Latin) ; and ο ανηρ, the man; difering, however, from | Ελεως εστι τοις αγαθοις. 10. Οι θηρευτοι θηρευουσι τους λαγωτ. 11. Ο them in the omission of in the genitive and dative singular | Merelows damßarei aynpw en aivov.
καλος ταώς. .
On the western side of the Pacific Ocean are the seas of Japan 1. Peacocks were sacred to Hera (Juno). 2. We admire Menelaus and Okhetsk, and the Yellow Sea and China Sea; and on the for his valour. 3. The poets call the morning rosy.fingered. 4. Truth eastern side are the inlets called the Gulf of California and (na Anderu) often does not satisfy the people. 5. Helen was the wife Queen Charlotte's Sound. of Menelaus. 6. Babylon produces many peacocks. 7. In the temples The ocean which rolls between Europe and America, and also of the gods are many pillars. 8. Hares are timid animals. 9. The between Africa and America, is usually divided into two parts voyage round (Mount) Athos was dangerous. 10. The palace has fine by the equator, the one being called the North Atlantic Ocean, chambers,
and the other the South Atlantic Ocean. The whole ocean ΕΣ ISE 18.-ENGLISH-GREEK.
receives the name Allantic, from its washing the shores of that 1. Μενελεως θαυμαζεται επι τη αρετη. 2. θαυμαζομεν την ροδοδακτυλον | part of Africa where the mountains of Atlas were situated, which Εω. 3. Πολλοι ταφ εν Βαβυλωνια τικτονται. 4. Εν τω της Ήρας νεα εστι the poets feigned were employed to support the heavens. The
5. Οι θηρευται ταως ενεδρευουσι. . 6. oi taw evedpevovTA. ITO Atlantic Ocean is bounded on the east by Europe and Africa, and των θηρευτων. . 7. Οι αγαθοι πολιται τον ανοητον λεων φευγονσι. .
on the west by America ; that part of it between Europe and EXERCISE 19.-GREEK-ENGLISH.
America is called, from ancient times, the Western Ocean. The 1. Avoid wild beasts. 2. A hand washes a hand. 3. Keep from Atlantic Ocean, taken between the limits of the Arctic Circle and the wasp. 4. The meadows bloom. 5. The soldiers sing their war the latitudes of 35° S. on the one side, and 55° S. on the other, song, 6. We know (try) gold and silver in (by) fire. 7. Many become is only about half the size of the Pacific Ocean. The South friends at the goblet (over their cups), but most (a greater number Atlantic Ocean contains few islands of any size, and no inlets of become) enemies. 8. Men are delighted with the harp and banqueting
consequence. The North Atlantic Ocean abounds in large and dances and songs of victory. 9. The Greeks worship Apollo and Poseidon (Neptune). 10. Industrious scholars read the works of islands, of which Great Britain and Ireland are the most noted; Xenophon with pleasure.
and in deep and numerous inland seas, whicii penetrate far into
the interior of both the Old and New Worlds, and which have EXERCISE 20.-ENGLISH-GREEK.
rendered the nations which possess its seaboard the most com1. Φευγε τους θηρας. 2. θηρα φευγουσι. 3. Τας χειρας νιζε. 4. Απεχεσθε mercial and enterprising people on the face of the globe. The των ψηνων. 5. Στρατιώτης το παιανι τερπεται. 6. 'o Talav Tous Otpatiwtas Mediterranean Sea and the Baltic Sea are but arms of the North τερπε.. 7. Ω σπουδαιοι μαθηται, τα του Ξενοφωντος βιβλια αναγιγνωσκετε. 8. Atlantic Ocean, on the east; and the Caribbean Sea, the Gulf of Ta tov Zevopwvtos Biblia avagyoyowokOVTA, ÚTO TWY orovda'w muOntwr. 9. Mexico. Hudson Bay, and Davis Strait, arms of the same on Τερπομεθα τους καλοις λειμoσι. 10. Οι λειμώνες θαλλoυσι. 11. Οι ποιηται the west. On the eastern shores, few large rivers, except the τον Απολλω σεβονται. 12. Τον Ποσειδω σεβεται ο ποιητης.
Niger, discharge themselves into its waters; but on the western
shores it receives the great rivers La Plata, the Orinoco, the LESSONS IN GEOGRAPHY.-XXI.
Maränon or Amazons, and the Mississippi, the largest water-ways
on the surface of the globe. NATURAL DIVISIONS OF THE EARTH'S SURFACE
The Indian Ocean rolls between the Atlantic and Pacific Oceans, (continued).
washing the eastern shores of Africa, the southern shores of Asia, With regard to the natural divisions of the water, the sea and the western shores of Australia ; whence its western, which surrounds the land is divided into three great sections, northern, and eastern boundaries are manifest; on the south it called oceans, exclusive of the comparatively small portions lying is bounded by the Pacific and Antarctic Oceans. This ocean within the polar circles, which are denominated the Arctic and contains many islands, the most important of which are MadaAntarctic Oceans. These three sections are :-1st. The Atlantic gascar and Ceylon; and several bays and golfs, such as the Bay Ocean, extending from the Arctic Circle to the Antarctic Circle, a of Bengal, the Arabian Sea, the Persian Gulf, the Red Sea or distance of 9,188 miles, and from the western coasts of the Old Arabian Gulf, etc. World to the eastern coasts of the New World, varying in The ocean (from the Greek okeavos, o-ke-a-nos, the great outbreadth from 1,818 miles, the distance between Sierra Leone ward sea surrounding the world) means collectively, all the water and Cape Roque, to 4,135 miles, the distance between the Cape which surrounds the earth; or, individually, any very large of Good Hope and Cape Horn. 2nd. The Pacific Ocean, also ex- expanse of water. tending from the Arctic Circle to the Antarctic Circle, and from the The term sea (from Saxon, sæ) is used in the same sense, both eastern coasts of the Old World to the western coasts of the New collectively and individually; but it is also applied to a smaller World, varying in breadth from sixty miles at Behring Straits, portion of water, and is often synonymous with the term gulf, to about 11,000 miles at the equator, and then tapering to 5,277 from the Italian golfo, which is a bay, or opening of the sea into miles, the distance between Cape Horn and Tasmania. 3rd. the land, either by a wide or a narrow opening. When the The Indian Ocean, extending from the Tropic of Cancer to the mouth of the opening into the land is wide, it is more usually Antarctic Circle, a distance of 6,214 miles, and from the eastern called a bay, from the French baie ; and when narrow, a gulf. coasts of Africa to the western coasts of Australia, varying in When the sea penetrates far and wide into the land, the collection breadth from 3,491 miles at the equator, to 6,126 miles, the of water is then called an inland sea ; such are the Mediterranean distance between the Cape of Good Hope and Van Diemen's Sea and the Baltic Sea, the one in the south and the other in the Land.
north of Europe. The ocean which rolls between Asia and America, called the The Arctic Ocean is the sea that surrounds the north pole, or Pacific, from the smoothness of its waves, and sometimes the rather that lies within the Arctic Circle; its boundaries are not Great South Sea, from its vast extent, exceeds the whole surface exactly known, that is, it is not yet ascertained how much land of the dry land. It is usually divided into two parts by the lies within this zone, and, consequently, the extent of sea is eqnator, the portion which lies in the northern hemisphere being equally unascertained. Whether Greenland extends to or falls called the North Pacific Ocean, and that in the southern hemi- short of the north pole has not yet been discovered; and the sphere the South Pacific Ocean. It is bounded on the east by limits of North America have not quite been determined. This the western and north-western shores of America, and on the sea, besides the greater part of Greenland, contains Nova Zembla, west by the eastern coasts of Asia and Australia. Towards the the extreme north of Europe, the Liakhov Islands or New Siberia, eastern side, and in the torrid zone, the face of this ocean is and others, and some north of Baffin Bay. The White Sea is studded with innumerable groups of islands, all remarkably on the borders of the Arctic Ocean. The Antarctic Ocean, small. These consist generally of coral reefs, rising up like a though considered as being likely to contain more land, is still wall from unfathomed depths, and emerging but a little way less known than the Arctic Ocean; and if both were equally free above the level of the sea. The most noted of these groups is of land, they would be of the same size within the Arctio and that called the Society Islands, the chief of which is Otaheite or Antarctic Circles. Tahiti (for an engraving of Otaheite see Vol. I., page 237); but Lakes are large or small portions of water wholly surrounded Il of them are the works of insects, both minute and innu- by land; some of these are so large as to be called seas, such as nerable, whose incessant labours are gradually forming new the Caspian Sea, the Sea of Aral, etc. groups at the bottom of the ocean. The situation of these A channel is a narrow passage between two seas, or two parts slands is such that, although lying between the tropics, the tem- of the same sea; as, the English Channel, between the North erature of their atmosphere is so moderated by the surrounding Sea or German Ocean and the Atlantic. cean that they enjoy the most delightful climate in the world. As appropriate illustrations to the present lesson on the