" said Polly. "The walls don't go out to the roof. It goes on. I don't know how far."

to step from rafter to rafter,cheap coach bags, and between them there was only plaster. If you stepped on this you would find yourself falling through the ceiling of the room below. Polly had used the bit of the tunnel just beside the cistern as a smugglers' cave. She had brought up bits of old packing cases and the seats of broken kitchen chairs, and things of that sort, and spread them across from rafter to rafter so as to make a bit of floor. Here she kept a cash-box containing various treasures, and a story she was writing and usually a few apples. She had often drunk a quiet bottle of ginger-beer in there: the old bottles made it look more like a smugglers' cave.
Digory quite liked the cave (she wouldn't let him see the story) but he was more interested in exploring,Link.
"Look here," he said. "How long does this tunnel go on for? I mean, does it stop where your house ends?"
"No," said Polly. "The walls don't go out to the roof. It goes on. I don't know how far."
"Then we could get the length of the whole row of houses."
"So