Why Europe is drawn above Africa on the world map

 By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

14 March 2010

There are two ways of drawing the map of the world. The one we are used to has Africa at the centre, Asia to the left and the Americas to the right. In the USA, however, they draw it differently: The Americas are at the centre, Africa to the right and Asia to the left.

The US version creates a small problem: Everybody knows that on the compass, the East is to the right and the West to the left. But in the American world map, Eastern countries are on the left hand side.

Placing Africa at the centre has two advantages. First, all the major land masses can be drawn in full without splitting them. Secondly, the continent of Europe also lies in the middle zone. That was important to European explorers; their continent had to occupy “the centre of everything”.

Furthermore, Europe had to be placed “above everything” as well, thus it was drawn above Africa even though the latter is actually higher than the former. If you recall last week’s argument, “up” means away from the centre of the Earth and Africa is, on average, farther from the centre (and therefore higher) than Europe.

Thus my first though regarding why Egypt is drawn above Uganda on the map is that the pride of European explorers couldn’t allow them to think otherwise: to them, nothing could be “higher” than Europe.

However; in the same way that drawing Europe (and Africa) in the middle makes geometrical sense (the continents appear in full), there is a second reason also arising from geometry: and this is where nuts and bolts come into the story.

We are accustomed to tightening nuts and bolts by turning them clockwise – from left to right. There are only a few rare cases where turning this way would loosen the nut. In geometry this is called a right-handed screw.

Now; the X-axis runs from left to right on a piece of paper while the Y-axis points away (from the person drawing). Note that Y doesn’t point “up” since that means going vertically out of the paper!

X and Y represent a two dimensional plane, but the physical world has three dimensions. How then do we draw the third one?

The third axis, Z, is always drawn such that the three (X, Y, and Z) form a right-handed set. That is; if you imagine a screw being turned from X to Y, it should move in the direction of Z.

On a piece of paper, turning from X to Y means turning anti-clockwise. Doing that to a screw would loosen it, that is, it moves upwards. Therefore, the Z axis points vertically upwards from the paper.

Now think about how the Earth rotates. We know it rotates because every day we see the sun rising from the East moving across the sky and setting in the West. This means that the planet is rotating from West to East.

If you turn a right handed screw in such a manner, which way would it move – Northwards or Southwards? Think; Think; Think…

It moves Northwards. Thus the Z axis of the rotating planet points North. And since we normally draw the Z direction pointing “up”, it follows that the Northern regions of the world map should be placed up and the Southern ones down.