Page:Van Loon--The Story of Mankind.djvu/40

4 In the beginning, the planet upon which we live was (as far as we now know) a large ball of flaming matter, a tiny cloud of smoke in the endless ocean of space. Gradually, in the course of millions of years, the surface burned itself out, and was covered with a thin layer of rocks. Upon these lifeless rocks the rain descended in endless torrents, wearing out the hard granite and carrying the dust to the valleys that lay hidden between the high cliffs of the steaming earth.

Finally the hour came when the sun broke through the clouds and saw how this little planet was covered with a few small puddles which were to develop into the mighty oceans of the eastern and western hemispheres.

Then one day the great wonder happened. What had been dead, gave birth to life.

The first living cell floated upon the waters of the sea.

For millions of years it drifted aimlessly with the currents. But during all that time it was developing certain habits that it might survive more easily upon the inhospitable earth. Some of these cells were happiest in the dark depths of the lakes and the pools. They took root in the slimy sediments which had been carried down from the tops of the hills and they became plants. Others preferred to move about and they grew strange jointed legs, like scorpions and began to crawl along the bottom of the sea amidst the plants and the pale green things that looked like jelly-fishes. Still others (covered with scales) depended upon a swimming motion to go from place to place in their search for food, and gradually they populated the ocean with myriads of fishes.

Meanwhile the plants had increased in number and they had to search for new dwelling places. There was no more room