True, there were probably warmer intervals in this intense cold, when the more southern animals came and went, for we find bones of the hippopotamus, hyena, and others buried between the glacial beds
in the south of England. But there is no doubt that at this time numbers of land-animals must have perished, for in England alone, out of fifty-three known species which lived in warmer times, only twelve survived the great cold, while others were driven southward, never to return.
Moreover, when the cold passed away, and the country began again to be covered with oak and pine forests where animals might feed and flourish, we find that a new enemy had made his appearance. Man—active, thinking, tool-making man—had begun to take possession of the caves, making weapons out of large flints bound into handles of wood, and lighting fires by rubbing wood together, so as to protect himself from wild beasts and inclement weather.
Many and fierce must have been his conflicts, for the wild beasts were still strong and numerous, and man had not yet the skill and weapons which he has since acquired. But, rough and savage though he may have been, he had powers which made him superior to all