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and zoology, have been inserted, with the view of exciting the attention of the youthful pupil, and suggesting to the teacher profitable subjects of oral instruction.
No alteration has been made upon that part which treats of the terrestrial and celestial globes ; extensive experience having proved the previous completeness of that portion of the subject.
Important additions have been made in the department of descriptive astronomy. Notices of the nebulæ, double stars, and comets will be found, together with much valuable matter that did not appear in former editions.
Numerous wood-cuts have been inserted to elucidate several parts of the work, particularly that portion relating to the siderial heavens. Too little attention is, in most schools, paid to the acquisition of a knowledge of the stars. The assistance which is now furnished will, it is hoped, induce some to make the attempt.
An Epitome of Ancient Geography, as copious as the limits of the work would allow, has been added to this edition. In those cases where it is not thought necessary to require the pupil to commit this part to memory, the careful perusal of it, with constant reference to a good map, will be attended with considerable advantage.
Oct. 10, 1845.
-Hindostan, 164.—India beyond the Ganges, 169.- Isles of
GEOGRAPHY AND ASTRONOMY,
DEFINITIONS. GEOGRAPHY is a description of the earth.—The surface of the earth contains land and water. The great collections of water are called oceans, the smaller seas.
A bay or gulf, is a part of the sea running into the land; as, the Bay of Biscay, the Gulf of Venice.
A strait is a narrow part of the sea running between two countries, and connecting two seas: as the Strait of Dover, the Strait of Gibraltar, &c.
A lake is a considerable body of inland fresh water; as the Lake of Geneva, Lake Ontario, &c.
A considerable stream of inland water, which runs into the sea, is called a river.
The expansion of a river into an arm of the sea is termed an estuary.
A very great extent of land is called a continent.
An island is an extent of land surrounded by the sea; as Great Britain, Jamaica, &c.
A peninsula is a tract of land nearly surrounded by water. Where it is joined to some other land by a narrow neck, this is called an isthmus.
A promontory is a point of land stretching far into the sea, the end of which is called a cape; as the Cape of Good Hope.
OF THE EARTH IN GENERAL. The form of the earth is that of a globe flattened at the poles.
That the earth is a globe is proved by the following facts :-)st, As a vessel at sea approaches, the upper part of its rigging is seen before the hull becomes visible. 2nd, The shadow of the earth, as seen on the moon during an eclipse of that body, is circular. 3rd, Navigators have often sailed round the earth.
The circumference of the earth is about 25,000 miles, its diameter is nearly 8000 miles. Its surface contains nearly 197,000,000 square miles.
The equatorial diameter exceeds the polar by 26 miles. The force acquired by the earth's revolution upon its axis is necessarily greater at the equator than at the poleshence it is, that whilst the earth is flattened at the poles, it swells out at the equator.
The earth is divided into four quarters, Europe, Asia, and Africa, forming the eastern hemisphere or old world; and America constituting the western hemisphere or new world.
The three old continents are united together, but what approach America makes to Asia across the North Pole, is not yet accurately ascertained.
More than two-thirds of the earth is covered with water. The largest of the oceans, the Pacific, is between Asia and America; the Atlantic separates America from Europe and Africa; the Indian ocean is to the south of Asia.
The dry land, whether consisting of islands or continents, can only be considered as so much of the rough surface of the globe as happens to have an elevation sufficient to raise it above the level of the waters. By far the largest portion is in the northern hemisphere. The greatest depth of the ocean is not known, but its valleys do not probably descend below the surface of the sea further than the mountains rise above it, that is, about four miles. The ocean is of incalculable value to man