$44 ok THE LATITUDE AND LONGITUDE.

Having fixed the position of the poles andequator, it will be easy to form a notionof any other circles that can be drawn uponthe globe. A meridian, for instance, is a cer-tain great circle, which is supposed to passthrough the two poles, and to divide the easternhalf of the earth from the western half. Andbecause any place, which lies to the east or westof another, may have a circle of this kinddrawn through it, you 'Will readily perceive thatthere may be as many meridians as there areplaces of different situations. The meridian ofany particular place is also to be known, by itsbeing that circle in which the fun is always tobe found at noon, or when he is at an equaldistance both from the point where he rises, andthe point where he sets.

These are the principal circles concerned inthe present subject; and if they be properly un-derstood, what follows will be found perfectlyeasy. The equator, for instance, is representedas a boundary, which separates the northernfrom the southern hemisphere; and the lati-tude of a place is its distance north or southfrom this circle. If the place lies in thenorthern hemisphere, it is said to have northlatitude; and if it lies in the southern hemi-sphere, it is said to have south latitude: so thatthe latitude of any place will be greater or less,according as it is farther from, or nearer to the

equator.

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