Image from page 78 of "Map projections" (1912)
Title: Map projections
Authors: Hinks, Arthur Robert, 1873-1945
Publisher: [London] Cambridge University Press
Contributing Library: Mississauga - University of Toronto
Digitizing Sponsor: Ontario Council of University Libraries and Member Libraries
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nd it has theadvantage over Mollweides that the angles of intersection of themeridians and parallels are not so greatly altered towards theeastern and western edges of the sheet. It can be constructed very readily when we have a tableof the rectangular coordinates of the intersections for the zenithalprojection, by plotting the xs unchanged and halving thejs. It is clear that there is a whole class of projections of thiskind that might be constructed. But it is only the equal areaproperty that is preserved unaltered in the orthogonal projectionon the plane, and only the 2 : I reduction that offers any specialconvenience. Breusings projection. This is an attempt to obtain a mean between the advantagesof the zenithal equal area and the zenithal orthomorphic pro-jections. The radii are the geometrical means between the radiiof those two projections, or R = 2 Vtan^sin $£ This formula gives distances from the centre slightly greaterthan the true distances, but not so exaggerated as in the
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(=H 64 CONVENTIONAL PROJECTIONS orthomorphic. It is not much used, and is of no special interest.The radii for each io° are given in Table VIII, p. 120. The globular projection. This projection, often used in atlases for the World in TwoHemispheres, is very simple, but has no other merits. It isconstructed as follows: The central meridian and the equatorare two equal straight lines at right angles. The equator isdivided into equal parts ; and the meridians are arcs of circlespassing through these points of division, and the poles. The central meridian, and the circumference of the map, aresimilarly divided into equal parts ; and the parallels are arcs ofcircles passing through the points of division of the centralmeridian, and corresponding pairs of points on the circumference. Nells modified globular projection. This is a kind of mean between the ordinary globular andthe stereographic projection of the hemisphere. It is constructedas follows : The meridians and parallels are curves
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