Synopsis
Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.
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Présentation de l'éditeur
By these circles Longitude is measured. Longitude is distance east or west of a given place. Note. Every circle whether large or small is divided into 360 (degrees). Every degree is divided into 60 (minutes) and every minute into 60 (seconds). By Latitude alone we would only be informed of the distance North orS outh of theE quator. By Longitude alone we could only learn the distance East or West of a certain spot. When both Latitude and Longitude are given the exact spot can be readily found, as the circles cannot cut one another in more than two places, and Longitude East or West determines which of the two with exactitude. The Meridian passing through Greenwich is the one from which we measure Longitude. The French have chosen the circle passing through Paris, and so with other nations, but all measure latitude from theE quator. As will be seen from the shape of the earth and the division of the circle into 360 the greatest possible Latitude is 90 and the greatest possible Longitude 180 .T ime also may be used as a measure, for as every circle is divided into 360 ,and the earth turns round itself in 24 hours, it follows that 15 difference in Longitude means the difference of one hour in time earlier or later as we proceed West orE ast. Take particular care to observe that if we proceed East the time advances and if West the time decreases; that is to say, if it be 12 noon at Greenwich, it will be 1p.m. at any place 15 degrees East, and 11 a.m. at any place 15 degrees West. Zones. Four of the parallels of Latitude have special names given them and the spaces between them have also special names: Placed 23 28 North of theE quator is the Tropic of Cancer. At 23 28 South of theE quator is the Tropic of Capricorn. At 23 28 from theN orth Pole is placed the Arctic Circle. At 23 28 from theS outh Pole is placed the Antarctic Circle. The space between the Tropics
(Typographical errors above are due to OCR software and don't occur in the book.)
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