Indeed I once knew a lady who half-humorously suggested that the cave was a crèche, in which the babies were put to be specially safe, and that coloured animals were drawn on the walls to amuse them; very much as diagrams of elephants and giraffes adorn a modern infant school. And though this was but a jest, it does draw attention to some of the other assumptions that we make only too readily. The pictures do not prove even that the cave-men lived in caves, any more than the discovery of a wine-cellar in Balham (long after that suburb had been destroyed by human or divine wrath) would prove that the Victorian middle classes lived entirely underground. The cave might have had a special purpose like the cellar; it might have been a religious shrine or a refuge in war or the meeting-place of a secret society or all sorts of things. But it is quite true that its artistic decoration has much more of the atmosphere of a nursery than of any of these nightmares of anarchical fury and fear. I have conceived a child as standing in the cave; and it is easy to conceive any child, modern or immeasurably remote, as making a living gesture as if to pat the painted beasts upon the wall. In that gesture there is a foreshadowing, as we shall see later, of another cavern and another child. But suppose the boy had not been taught by a priest but by a professor, by one of the professors who simplify the relation of men and beasts to a mere evolutionary variation. Suppose the boy saw himself, with the same simplicity and sincerity, as a mere Mowgli running with the pack of nature and roughly indistinguishable from the rest save by a relative and recent variation. What would be for him the simplest lesson of that strange stone picture-book? After all, it would come back to this; that he had dug very deep and found the place where a man had drawn a picture of a reindeer. But he would dig a good deal deeper before he found a place where a reindeer had drawn a picture of a man. That sounds like a truism, but in this connection it is really a very tremendous truth. He might descend to depths unthinkable, he might sink into sunken continents as strange as remote stars, he might find himself in the inside of the world as far from men as the other side of the moon; he might see in those cold chasms or colossal terraces of stone, traced in the faint hieroglyphic of the fossil, the ruins of lost dynasties of biological life, rather like the ruins of successive creations and separate universes than the stages in the story of one. He would find the trail of monsters blindly developing in directions outside all our common imagery of fish and bird; groping and grasping and touching life with every extravagant elongation of horn and tongue and tentacle; growing a forest of fantastic caricatures of the claw and the fin and the finger. But nowhere would he find one finger that had traced one significant line upon the sand; nowhere one claw that had even begun to