What is the revolution of the primary planets round the sun called? What is the rotation of a planet on its own axis called? To what science does a knowledge of the size, motions and distances of the heavenly bodies belong? What is the order of the planets, as it respects distance from the sun? What is the diameter of the sun, and in what time does it perform a rotation on its axis? What is the distance of Mercury from the Sun? In what time does Mercury perform a revolution round the Sun? In what time on its own axis? What is the diameter of Mercury? Has mercury any moons? Let the same questions be asked with respect to each of the other planets. OF THE EARTH ÎN GENERAL. The earth is a large globe or sphere, which is nearly eight thousand miles in diameter, consequently its circumference is nearly twenty-five thousand miles. The whole surface of the globe contains about two hundred millions of square miles. Nearly one-fourth part of the surface of the globe is land, the rest water. There are two great divisions of land, the Eastern and Western Continents. There are five great divisions of water, the Pacific, Atlantic, Indian, Northern, and Southern Oceans. The number of inhabitants now existing on the globe, is estimated at eight hundred millions. What is Geography? QUESTIONS. What is the earth, and what is its size? What number of square miles does the surface of the earth contain? What portion of the earth's surface is land? Name the two great divisions of land. What number of people are on the globe? Name the five great divisions of water. B QUESTIONS ON THE MAP OF THE WORLD. What ocean is situated between Asia and America? Where is the Indian Ocean situated? What ocean is that which has America on one side, and Europe and Africa on the other? What sea separates Europe from Africa? EXPLANATIONS NECESSARY TO THE USE OF MAPS. The surface of the earth is most correctly represented by an The axis of the earth is an imaginary line, conceived to pass through its centre, one extremity of which is called the North, or Arctic, and the other the South, or Antarctic pole. The Equator or Equinoctial is an imaginary line passing round the middle of the earth, situated at an equal distance from the two poles, and dividing it into two equal parts, called Hemispheres. The Ecliptic is a line which passes round the earth, and intersects the Equator in two opposite points, called the Equinoxes, and extends in two opposite points to the Tropics. Meridians are lines which pass round the earth, intersecting the Equator, and passing through both poles. Parallels of latitude are lines which pass round the globe parallel to the Equator. The Tropics are circles passing round the earth parallel to the Equator, 23 degrees from it. The circle north of the Equator, is called the Tropic of Cancer. The circle south of the Equator, is called the Tropic of Capricorn. The Polar circles pass round the earth 23 de-. grees from each of the poles. That north of the Equator is called the Arctic, that on the south the Antarctic circle. All circles on the globe are divided into 360 equal parts, called degrees, (marked °,) every degree into 60 minutes, (marked ',) or geographical miles. The line which bounds the sight on all sides where the earth and sky appear to meet is called the Horizon. The four principal points of the Horizon, north, south, east, and west, are called Cardinal Points. Between the cardinal points are four others, north-east, south-east, south-west, north-west. A map is a picture, or representation, of the whole or a part of the surface of the earth, and may be delineated on any plane or sphere. The top of a map is the north part, the bottom south, the right hand east, and the left hand west. Latitude is the distance of a place north or south of the Equator, and cannot exceed 90 degrees. Latitude is marked by numbers on the sides of maps. If the figures which denote the latitude increase from the bottom towards the top of the map, the country which the map represents lies north of the Equator. |