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Name the natural divisions of the land. Continents, islands, peninsulas, isthmuses, promontories, capes, and shores.

Describe these divisions.

A continent is a vast tract of land containing many countries, as Europe. An island is a portion of land surrounded by water, as Great Britain. A peninsula is a tract of land which is nearly surrounded by water, as the Morea in Greece. An isthmus is a piece of land joining two countries, and separating two seas, as the Isthmus of Panama. A promontory is a part of the land projecting into the sea, the extreme point of which is called a cape as the Cape of Good Hope. A shore is that part of the land which is washed by the sea.

How is the water divided?

Into oceans, seas, gulfs, bays, straits, lakes, and rivers.

How are these divisions defined?

An ocean is a vast extent of salt water not divided by land, as the Atlantic Ocean. A sea is a smaller collection of water than an ocean, as the Black Sea. A gulf is a part of the sea running up into the land, as the gulf of Genoa. A bay is a gulf of less extent, but having a wider opening. A small bay is called a creek, or harbour, or cove. A strait is a narrow part of salt water separating two countries, and joining two seas, or the opposite to an isthmus, as the strait of Dover. A lake is a portion of water entirely surrounded by land, being the reverse of an island, as the lake of Geneva. A river is a body of fresh water rising in the land and flowing into the sea, as the Thames. Where a river rises is called its source, and its mouth is where it empties itself into the sea. The bed of a river is the channel it flows through; and its basin is that part of a country through which

it flows, and by which it is drained. A river's banks is that part of the land, on both sides of it, which is washed by its waters.

What is the shape of the earth?

It is nearly round, and therefore does not form a perfect globe or sphere. It is an oblate spheroid. What is a globe or sphere?

A body everywhere perfectly round. The half of a globe is a hemisphere. The fourth part of a circle is called a quadrant, and consists of 90°.

How many kinds of globes are there? Two, the terrestrial and the celestial. The former is an artificial globe, on which the surface of the earth is delineated, with its continents, oceans, mountains, rivers, towns, &c. A celestial globe is an inverted representation of the starry Heavens.

In

Why do you call it an inverted representation? Because as we look at the Heavens they appear hollow or concave, whereas, on an artificial globe, they are made to have a convex appearance. order to have a correct representation of the Heavens, it would be necessary to procure a globe sufficiently large to allow of our getting inside, and having the stars and planets marked therein.

What are the north and south poles?

The extreme ends of the earth's axis, which is an imaginary line passing through the centre of the earth from north to south, and on which it is said to turn. What is the equator?

An imaginary line passing round the middle of the earth from west to east, and dividing it into two equal parts, called the northern and southern hemispheres. The equator is 90° from each pole.

What are meridian lines?

Meridian lines, or lines of longitude, are semi

circles, or half circles, cutting the equator at right angles, and extending from pole to pole.

What is an angle?

The inclination or opening between two straight lines. Angles are of three kinds; acute, obtuse, and right angles.

How are these angles defined?

One straight line standing upon another straight line, making the adjacent angles equal, each of them is a right angle, thus 90°. An acute angle is An obtuse angle

less than a right angle, thus 2. is greater than a right angle, thus

.

You have been speaking of lines, what is a line? That which has length and breadth, but no thickness. A straight line is one that lies evenly between its two points; or the nearest road between two points. A crooked line is one that lies unevenly between its two points.

What is a great circle?

A line encircling the earth, and dividing it into two equal parts, as the equator. A small circle is one which divides it into two unequal parts, as the tropics, and polar circles.

What is a circle?

A space enclosed by one line, called the circumference, all parts of which are equally distant from a given point called the centre. A point is that which has neither length, breadth, nor thickness.

What are the tropics?

Two small circles encircling the earth, and running parallel with the equator. The northern is called the tropic of Cancer; and the southern the tropic of Capricorn. They are 231° from the equator. Why are they called tropics?

From the Greek word, "Trepo" I turn, because

when the sun reaches either of them, it apparently turns back. It must be borne in mind that the sun is stationary, and that it is the earth which moves. When does the sun reach the tropic of Cancer?

The 21st June, which is our longest day; and when it is over the tropic of Capricorn, it is our shortest day, the 21st December.

How often does the sun cross the equator?

Twice in a year, the first time is on the 21st March, which is called the vernal equinox; and again on the 21st of September, which is the autumnal equinox. On these occasions the days and nights are equal all over the world.

When is the sun nearest to the earth, in winter or summer?

In winter; but it is colder to us because the rays of the sun are then more oblique or slanting.

Is the northern or southern hemisphere the colder? The southern, which is occasioned by there being more water in the south than in the north; for water absorbs heat. Captain Parry sailed within 90 of the north pole; but Captain Weddell could approach no nearer than 15° to the south pole; both being prevented proceeding farther on account of the ice which impeded them.

What are polar circles?

Two small circles which encircle the earth, being 2310 from the poles, or the same distance from the poles, as the tropics are from the equator.

You stated the earth was round, give some proof that such is the case.

If a ship start from a port, and always keep her head in the same direction, she will come back to the point whence she started, plainly demonstrating that she has made a circuit. If you stand on the sea shore, and watch a ship in the distance coming

towards you, you will observe the tops of the masts first, and then gradually the lower parts as she

comes nearer.

Why is the hull of the ship hidden from your view? In consequence of the rotundity of the water between the vessel and yourself.

Have you any other proof that the world is round? Yes, this is convincingly shewn by an eclipse of the moon, which is occasioned by the earth's shadow falling upon the moon, which shadow is observed to be round, and therefore the earth itself must be round, for no other than a round body can cast a round shadow.

How can the earth be round considering the inequalities on its surface?

Because the mountains, valleys, &c., on the earth's surface, do not lessen its spherical form, any more than the inequalities on the rind of an orange detract from its roundness.

What is the distance round the world called?

Its circumference, which is 360°, or nearly twentyfive thousand miles. All circles, however, large or small, are divided into the same number of degrees. What is meant by the earth's diameter ?

Its distance through the centre, which is nearly eight thousand miles: it is either polar or equatorial diameter.

Describe the difference between them.

By polar diameter is meant the distance through the centre of the earth from north to south, or from pole to pole; and by equatorial diameter, the like measurement from west to east. The equatorial exceeds the polar diameter by about twenty-six miles. This difference is caused by the flatness of the poles. Has the earth any motions?

It has two motions; one round its own axis, and

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