It's the best idea they have, anyway, so Childermass isn't about to dismiss it. He steps across the ice carefully, putting himself next to Strange and moving to put a hand on the other magician's shoulder, to help keep him steady on the ice.

"Then show me how. Mr. Norrell would write down spells for me to do often enough when he did not want to go out and do magic himself, so it can't be much more difficult than that."