There was a blacksmith once who had two pieces of iron which he wished to weld into one, and he took them just as they were, all cold and hard, and put them on the anvil, and began to hammer with all his might, but they were two pieces still, and would not unite. At last he remembered what he ought never to have forgotten; he thrust both of them into the fire, took them out red-hot, laid the one upon the other, and by one or two blows of the hammer they very soon became one.