Page:Small-boat sailing; an explanation of the management of small yachts, half-decked and open sailing-boats of various rigs; sailing on sea and on river; cruising, etc (IA smallboatsailing01knig).pdf/214

 were drawn as equidistant straight lines. This was correct so far as the parallels of latitude are concerned; but whereas the meridians of longitude are in fact furthest apart at the Equator and meet at the Poles, great error was produced by this projection. At last Kauffman, known as Mercator, introduced the chart called after him Mercator's Chart, which was at once recognised as being admirably adapted for the purposes of navigation. In the Mercator's chart, as in the Plane chart, the meridians of longitude are drawn as parallel equidistant straight lines; they are thus greatly distorted, and the Polar regions are magnified to an enormous extent; but the parallels of latitude are not drawn as equidistant, as in the Plane chart, but are distorted in proportion to the distortion of the meridians—that is, they are drawn further apart as the Poles are approached. For example, a degree of longitude on the latitude of Edinburgh, though appearing on Mercator's chart of the same length as a degree of longitude at the Equator, is in reality nearly double the length of the latter: a degree of latitude on the parallel of Edinburgh—as will be seen on inspecting a chart—is therefore magnified in like proportion, being drawn nearly twice as long as a degree of latitude on the Equator. By this projection, consequently, the relative shape of different regions of the Earth is approximately preserved.

The great advantage of Mercator's chart lies in the fact that, though upon it there is a distortion of