Scottish geographical magazine . the world from 25° North to aliout 20° from thePole—that part, in other words, which must remain coterminous Eastand West—can best be joined by making the gores of a globe touch eachother, not at their centres (Figure 2, Mercators) nor at their ends, asin Figure 6, but midway between—in the middle of the land belt of theworld, viz. at 45° N. Lat. 460 SCOTTISH GEOGRAPHICAL MAGAZINE. Let US now turn from the mechanical consideration of the thirtydegree gores of a globe (and they have proved very helpful in makingclear our progress) and consider the problem geomet
Scottish geographical magazine . the world from 25° North to aliout 20° from thePole—that part, in other words, which must remain coterminous Eastand West—can best be joined by making the gores of a globe touch eachother, not at their centres (Figure 2, Mercators) nor at their ends, asin Figure 6, but midway between—in the middle of the land belt of theworld, viz. at 45° N. Lat. 460 SCOTTISH GEOGRAPHICAL MAGAZINE. Let US now turn from the mechanical consideration of the thirtydegree gores of a globe (and they have proved very helpful in makingclear our progress) and consider the problem geometrically. Figure 8, which represents a solid both in section and elevation, butnot in perspective, shows a right-angled cone, ABD, tangent to a sphereEGtF at E and F; E and F being equivalent to 45° North this cone be slit up from any point in its base in a straight line to itsapex, it can be developed or laid out flat into exactly two-thirds of adisc BBCDD (Figure 9, which is a plan ). In the cone BA and DA. coincide—they are, in fact, one and the same line. In the developedor flattened disc BA and DA gape or widen out to the angle BAD,Avhich is one-third of a circle, viz. 120° of an arc. If we complete the circle we shall have (1) four parts each subtending60°, which when curled into a right-angled cone are tangent to the sphereEGF, and (2) also something over, that is, exactly two more such partsof 60° each. NoAv assuming the sphere to ])e a terrestrial globe Avith polar axisAC, Ave can project the parallels of latitude on to this cone. Wepropose to project a belt 45° Avide, or 22|° N. and S. of 45° NorthLatitude. This Avill give us 22i° North Latitude, and 67|° NorthLatitude as the boundaries of our zone of conical projection. AN ACCOUNT OF A NEW LAND MAP OF THE WORLD. 461 On Figure 8 the arc QF is bisected at X, and the arc FY is equalto the arc FX. XFY is an arc of 45°, and may be projected withapproximate accuracy on to the cone AD, at the
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectgeography, bookyear18
