Sisily was afraid she might lose the paper (perhaps, like her mother, she had some prescience of the future) and he had endeavoured to divert her thoughts by making "memory pictures" of the name and address after the method of a thought reader.

He had told her to picture a cat sitting on a window ledge, and that would fix the name in her mind.
"Purr"-- "Sill"-- there it was! As for the place, it was only necessary to imagine him wandering in a wood (he slyly suggested it)--Charleswood, and there they were again! Sisily had smiled wanly at these "memory pictures" and said she would always be able to remember the address of her mother's old friend by their means.
They were effectual enough in his own case.

The grotesque association of ideas brought the address to his mind when he first thought of seeking Sisily in London.

He decided to go to Charleswood as soon as he reached there.

The dying woman seemed quite certain her old friend was still in Charleswood, although it was twenty years since she had heard from her.
She had told Sisily that Mrs.Pursill's house was her own, and it had belonged to her parents before her.