The Round world and the sun's rays

The following fundamental facts concerning the earth are illustrated: the earth spins on its axis, making a complete turn each day. It also revolves round the sun, taking one year to complete each journey. Energy from the sun falls upon the earth and passes through the envelope of air which surrounds it. This energy is not evenly distributed, because the world is round. At the equator the sun’s rays meet the earth at right angles. At the Poles, the same amount of energy falls on a larger surface of the earth. Thus it is hot near the equator and cold at the Poles.