He knew that the flat had been occupied by a German clerk in the civil service, and his family.

This German was moving out then, and so the fourth floor on this staircase would be untenanted except by the old woman.

"That's a good thing anyway," he thought to himself, as he rang the bell of the old woman's flat.

The bell gave a faint tinkle as though it were made of tin and not of copper.

The little flats in such houses always have bells that ring like that.