Magic ring

The magic rings of Andrew Ketterley were a small collection of yellow and green finger rings, used to transport people to and from the Wood between the Worlds respectively.



Creation
The rings were created on Earth by Andrew Ketterley (in Earth-year 1900) from a magical powder he discovered in a box left to him by his part-fairy godmother Mrs. Lefay. The box is said to originate from Atlantis and the dust was discovered by Uncle Andrew and said to have been brought from another world. It is possible that the dust may have come from the Wood between the Worlds itself.

To work, the user must have skin contact with the rings, or skin contact with a person who is linked through skin contact to the rings. Upon touching a yellow ring, the user will be taken to the Wood between the Worlds, emerging from the pool corresponding to the world the user was present in at the time. From here, the user is able to enter any other world by touching a green ring and jumping into the pool corresponding to the world of choice.

Experimentation


After he had created them, Andrew spent a while experimenting by tying the yellow rings to guinea pigs. This resulted, to the delight of Andrew, in several guinea pigs disappearing entirely to 'another world', though of course they had no means of getting back, or telling him about it. Therefore, in order to test for sure whether it would be safe for human travel, he tricked Polly Plummer into touching one of the yellow rings. Shortly afterwards Digory did the same in order to rescue Polly, bringing with him two green rings. Digory found himself transported to the Wood between the Worlds where he found Polly and the various guinea pigs. Before returning, the two used the green rings to enter and explore the dying world of Charn, where Digory awakened Jadis, last empress and queen of Charn, from a centuries-old spell. Upon leaving with the yellow rings, and returning to their own world with the green rings, they inadvertantly brought Jadis back with them when she grabbed onto Polly's hair. This proved that one did not have to possess the ring for it to function, but rather, one could simply touch another person who possessed a ring.

Upon arriving on Earth, Jadis immediatly began to wreak havoc throughout London, with Uncle Andrew at her tail, and in the effort to return her to her own world, Digory, Polly, Jadis, Uncle Andrew, Frank the Cabby and his horse Strawberry ended up in Narnia to witness it's creation. At the end of their adventure, Digory was commanded by Aslan to bury the rings so that no one could have used them again. Digory buried the rings in his back garden.

In 1949, the Seven Friends of Narnia gathered together and conspired to retrieve the rings. Before Eustace and Jill were summoned back to Narnia, Peter and Edmund sneaked into the garden of Professor Kirke's old house and dug up the box containing the rings. However before they could use the rings, the remainder of the seven friends present were summoned to Aslan's Country when the train they were travelling on crashed. What became of the rings in the wreckage after their deaths however remains a complete mystery.

Theories
It is possible that the rings are attracted to strong magic, explaining why Digory and Polly are brought to the ruined palace of Charn where Jadis awaits and soon afterward are brought directly to the house in london where Uncle Andrew conducts his experimnents.