Globe Maps
Since the first globe was made by Martin Berhaim in 1492, globe maps have evolved greatly, until now they have become an essential education accessory that can be found on any student's desk or in any classroom.
Berhaim's first-ever globe is a museum piece, for it is inscribed with all the pseudo-scientific, superstitious, inaccurate and mythical knowledge that supplemented the little geographical information that was available to people in that age.
Only Europe, parts of Asia and the northern portion of Africa were explored. The rest of the world was completely shrouded in mystery. In fact, no one even knew how big the whole world was. The seas began to the west of Europe and the east of Asia; but how far they stretched on either side or whether there was any land mass in that uncharted void was anybody's guess.
Naturally, this led people to speculate wildly about the unknown parts of the world, and to give rise to legends about strange lands and incredible flora and fauna. Evidence of this can be found in Berhaim's first globe map. Modern scholars often refer to it as a source of information about geographical myths and legends that were popular in the 15th century.
In one of the Alice books, Lewis Carroll speaks of a new map that the inhabitants of wonderland had prepared. It was extremely accurate, but that was in a way the source of their problem. The had drawn it on a one-to-one scale, and now couldn't find enough space to spread it out. Naturally – a one-to-one map of the kingdom must be exactly as large as the kingdom itself!
Inhabitants of the normal world avoid that pitfall by constructing globe maps that are vastly smaller than the actual planet! The average scale on which commercial or normally available globe maps is constructed is about 1:40000000, or one to forty million. This means that a distance of one inch on a globe map corresponds to roughly 631 actual miles in the real world.
Modern globe maps are first printed on paper or other suitable media using high-definition computerized techniques, and may make use of satellite-derived data. These are then superimposed onto appropriately-sized spheres.
Since flat maps must undergo some degree of distortion when mapped onto a bent surface, globe makers must follow either of the two common principles of accuracy. If they privilege the accuracy of direction and shape, they would follow the doctrine of angle preservation. All the curves and their relative positions to each other are thus maintained, but the sizes of all the geographically significant entities will not correspond exactly to the scale adopted.
The principle of area preservation is also followed by some globe map makers, under which the size of each land mass or water body corresponds exactly (according to the adopted scale of course) to the real-world entities they represent. However, the position and direction of the places in relation to each other are not always totally accurate.
These distortions are minor enough that they can be ignored for all practical purposes. However, reputable globe map makers often provide information regarding which principle was used in the manufacture of a particular globe, and you may base your purchase decision on that.
Modern globes are normally tilted to represent the significant tilt of our planet with reference to its orbital plane. In fact, this tilt and the resultant wobble is the cause of the change of seasons on earth. The globe is usually held within the bracket of a metallic semi-circular spine that represents the meridian. In costlier or classier versions, though, the meridian may be a full circle and made of wood. In some versions, the equator too is represented by a wooden circle, effectively enclosing the globe between two circles perpendicular to each other and dividing the surface of the map into four equal sectors.
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