They came and stood together at the edge looking down into the smooth water. It was 
full of the reflection of the green, leafy branches; they made it look very deep.
    
    "We haven't any bathing things," said Polly.
    
    "We shan't need them, silly," said Digory. "We're going in with our clothes on. Don't 
you remember it didn't wet us on the way up?"
    
    "Can you swim?"
    
    "A bit. Can you?"
    
    "Well-not much."
    
    "I don't think we shall need to swim," said Digory "We want to go down, don't we?"
    
    Neither of them much liked the idea of jumping into that pool, but neither said so to 
the other. They took hands and said "One-Two-Three-Go" and jumped. There was a great 
splash and of course they closed their eyes. But when they opened them again they found 
they were still standing, hand in hand, in the green wood, and hardly up to their ankles 
in water. The pool was apparently only a couple of inches deep. They splashed back on to 
the dry ground.
    
    "What on earth's gone wrong?" said Polly in a frightened voice; but not quite so 
frightened as you might expect, because it is hard to feel really frightened in that 
wood. The place is too peaceful.
    
    "Oh! I know," said Digory, "Of course it won't work. We're still wearing our yellow 
rings. They're for the outward journey, you know. The green ones take you home. We must 
change rings. Have you got pockets? Good. Put your yellow ring in your left. I've got two 
greens. Here's one for you."
    
    They put on their green rings and came back to the pool. But before they tried 
another jump Digory gave a long "O-ooh!"
    
    "What's the matter?" said Polly.
    
    "I've just had a really wonderful idea," said Digory. "What are all the other pools?"
    
    "How do you mean?"
    
    "Why, if awe can get back to our own world by jumping into this pool, mightn't we get 
somewhere else by jumping into one of the others? Supposing there was a world at the 
bottom of every pool."
    
    "But I thought we were already in your Uncle Andrew's Other World or Other Place or 
whatever he called it. Didn't you say-"
    
    "Oh bother Uncle Andrew," interrupted Digory. "I don't believe he knows anything 
about it. He never had the pluck to come here himself. He only talked of one Other World. 
But suppose there were dozens?"
    
    "You mean, this wood might be only one of them?"
    
    "No, I don't believe this wood is a world at all. I think it's just a sort of 
in-between place."
    
    Polly looked puzzled. "Don't you see?" said Digory. "No, do listen. Think of our 
tunnel under the slates at home. It isn't a room in any of the houses. In a way, it isn't 
really part of any of the houses. But once you're in the tunnel you can go along it and 
come into any of the houses in the row. Mightn't this wood be the same?-a place that 
isn't in any of the worlds, but once you've found that place you can get into them all."
    
    "Well, even if you can-" began Polly, but Digory went on as if he hadn't heard her.
    
    "And of course that explains everything," he said. "That's why it is so quiet and 
sleepy here. Nothing ever happens here. Like at home. It's in the houses that people 
talk, and do things, and have meals. Nothing goes on in the inbetween places, behind the 
walls and above the ceilings and under the floor, or in our own tunnel. But when you come 
out of our tunnel you may find yourself in any house. I think we can get out of this 
place into jolly well Anywhere! We don't need to jump back into the same pool we came up 
by. Or not just yet."
    
    "The Wood between the Worlds," said Polly dreamily. "It sounds rather nice."
    
    "Come on," said Digory. "Which pool shall we try?"
    
    "Look here," said Polly, "I'm not going to try any new pool till we've made sure that 
we can get back by the old one. We're not even sure if it'll work yet."
    
    "Yes," said Digory. "And get caught by Uncle Andrew and have our rings taken away 
before we've had any fun. No thanks."
    
    "Couldn't we just go part of the way down into our own pool," said Polly. "Just to 
see if it works. Then if it does, we'll change rings and come up again before we're 
really back in Mr Ketterley's study."
    
    "Can we go part of the way down?"
    
    "Well, it took time coming up. I suppose it'll take a little time going back."
    
    Digory made rather a fuss about agreeing to this, but he had to in the end because 
Polly absolutely refused to do any exploring in new worlds until she had made sure about 
getting back to the old one. She was quite as brave as he about some dangers (wasps, for 
instance) but she was not so interested in finding out things nobody had ever heard of 
before; for Digory was the sort of person who wants to know everything, and when he grew 
up he became the famous Professor Kirke who comes into other books.
    
    After a good deal of arguing they agreed to put on their green rings ("Green for 
safety," said Digory, "so you can't help remembering which is which") and hold hands and