'I think I have said how much hotter than our own was the weather of this Golden Age. I cannot account for it. It may be that the sun was hotter, or the earth nearer the sun. It is usual to assume that the sun will go on cooling steadily in the future. But people, unfamiliar with such speculations as those of the younger Darwin, forget that the planets must ultimately fall back one by one into the parent body. As these catastrophes occur, the sun will blaze with renewed energy; and it may be that some inner planet had suffered this fate. Whatever the reason, the fact remains that the sun was very much hotter than we know it.

'Well, one very hot morning—my fourth, I think—as I was seeking shelter from the heat and glare in a colossal ruin near the great house where I slept and fed, there happened this strange thing: Clambering among these heaps of masonry, I found a narrow gallery, whose end and side windows were blocked by fallen masses of stone. By contrast with the brilliancy outside, it seemed at first impenetrably dark to me. I entered it groping, for the change from light to blackness made spots of colour swim before me. Suddenly I halted spellbound. A pair of eyes, luminous by reflection against the daylight without, was watching me out of the darkness.