AS yet the early savage had been living in a world not realised. It was not until the ice retreated, and Europe was left with a temperate climate, that he could begin methodically to adapt nature to his own ends. His tools were now no more made by chipping, but by pressure or by grinding, and were wonderfully effective. He had made them still more so by fitting handles to them. He could build wooden houses, and enjoy such luxuries as wooden furniture and wooden articles for table use. The discovery of pottery made it possible for him to try new foods, and to make them more appetising by cooking. The old hunting life gave way to the more settled life of the herdsman or shepherd, tending his sheep and cattle for the food and milk they could give him. By domesticating wheat and barley, he in turn became an agriculturist, who must wait for his crops to ripen in due season. He had to work harder, but his labours were more profitable, and in order to lighten the work, he invented the plough and taught the ox to draw it, instead of himself having " to groan over the heavy hoe." This advance had other results. Already in the past men had probably banded themselves together for the purposes of hunting. Now stronger motives for union appeared. Increasing herds and food supplies had to be protected against the greed of neighbours. The best way to do this was by forming a permanent settlement and surrounding it with a ring-fence of earth and stone, or by building lake-villages on piles. In Switzerland there has been discovered a village where fifty thousand piles had been driven into water eight feet deep. Such an achievement proves a high degree of social organisation. So, too, the gigantic columns of Stonehenge could not have been brought together and erected without skilled direction and co-operation. Greater comfort led to specialisation. There arose the trades of the potter and the weaver, the farmer and the miner, who exchanged their products by barter. At Brandon in Suffolk the trade of flint mining and knapping is still carried on where Neolithic miners loosened their flint stones with a red-deer's antler for a pick.