Page:A Short History of the World.djvu/62

42 A Short History of The World America it reached Ohio. There would be warmer spells of a few thousand years and relapses towards a bitterer cold. Geologists talk of these wintry phases as the First, Second, Third and Fourth Glacial Ages, and of the interludes as Interglacial Periods. We live to-day in a world that is still impoverished and scarred by that terrible winter. The First Glacial Age was coming on 600,000 years ago ; the Fourth Glacial Age reached its bitterest some fifty thousand years ago. And it was amidst the snows of ^r:.:J^i^MA A MAMMOTH this long universal winter that the first man-hke beings lived upon oiu planet. By the middle Cainozoic period there have appeared various apes with many quasi-human attributes of the jaws and leg bones, but it is only as we approach these Glacial Ages that we find traces of creatures that we can speak of as " almost human." These traces are not bones but implements. In Europe, in deposits of this period, between half a million and a million years old, we find flints and stones that have evidently been chipped intentionally by some handy crea- ture desirous of hammering, scraping or fighting with the sharpened