Elysium, which is also called "the Elysian fields," or "the Islands of the Blest," was a very delightful place, like the most beautiful country in the finest weather, never too hot or too cold, and full of sweet scents and sounds. There the souls of the happy enjoyed forever, without ever getting tired, whatever had given them the most pleasure upon earth--hunting, or war, or learning, or music, or whatever it might be: only all their pleasures became innocent and noble, and even if they fought, it was all in friendship and without harm. Nothing was quite real there: it was more like a beautiful and happy dream, lasting forever. Some of the very best and greatest human souls were taken up into Olympus and made "Demi-gods," that is to say "Half-gods"; but of course this was a very rare honor. The dream of Elysium was thought to be reward enough for the souls which, in their lives, had done more good than evil. Tartarus, the place of torment, was a very different place, as I need not say. It was farther below the earth than the earth is below the sky, and was surrounded by three brazen walls, and by Phlegethon, the river of Fire. The only entrance was through a high tower, with gates which not even the gods could open, and guarded by the three-headed dog Cerberus, which never slept; and the air was three times darker than the darkest midnight, lighted only by the terrible flames of Phlegethon. The jailers were Nemesis and the Furies. Nemesis is the great stern power who never allows the guilty to escape from their just punishment, nor the good to lose their just reward. If people are happier or more fortunate than they deserve to be, she always, either in this life or in Hades, gives them enough misery at last, until they are just as happy or unhappy as they deserve to be, and neither less nor more; and if they seem less happy or less fortunate than they deserve, she makes it up to them in the end. She is often so strangely slow in coming, that she has been called lame. But she always comes at last: if she is slow, she is sure.