SECTION XI. 251 the maps of the worldare generally drawn in two large hemis- pheres. Note here, That it is impossible to represent a spherical body exactly in its due proportion upon a plane ; and therefore the artificial-meridians or lines of longitude, parallels of latitude, &c. are placed at such different distances by certain rules of art, and the degrees markedon them areoften unequal ; but so drawn as may most commodiously represent the situation of the several parts of the earth with regard to one another. The meridian or circumference of these circles is divided into four quarters, and eachmarked with 90 degrees beginning from the equator and proceeding toward the poles. These figures or numbers shew the latitude of every place in the earth, or its distance from the equator, and at every 10 degrees there is a Parallel of latitude drawn on purpose to guide and direct the eye in seeking the latitude of any place. Theequator of each hemisphere is divided into 1S0parts, which makes 360 in the whole : And the several meridians -or lines of longitude, cutting the equator at every 10 degrees, guide and direct the eye to find the longitude of any place required. As the equator, the several lines of longitude, of latitude, &c. cannot be represented on a plane exactly as they are on a globe; so neither can the several parts of the world, kingdoms, provinces, islands, and seas be represented in a map exactly in the same proportion as they stand on a globe. But as the divisions of degrees in a map are bigger or less, so the parts of the land and sea are represented there bigger or less in a most exact pro- portion to thoselines of longitude and latitude among which they are placed. Therefore though the length or breadth, or distance of places on a map of the world cannot be measured by a pair ofcompasses as they maybe on a globe, yet you may count the number ofde- grees to which such lengths, breadths or distances correspond, and thereby you maycompute their real dimensions ; though not alwaysso well as on a globe ; of which hereafter. Titus much shall suffice concerning maps that represent the whole world, or theglobe of earth and water. Let us nextconsider those maps which represent particular parts of the . world, kingdoms or provinces, these are generally drawn in a large square, and are to be considered as parts of a projection on the plane of the meridian. From the top to or toward the bottom of the square are drawn meridians or lines of longitude ; and the number of degrees of longitude are divided and marked-on the upper and under- most line of the square. Front side to side are drawn parallels of latitude, and the degrees of latitude are marked on the two
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