She handed him the letter she had taken from the long blue envelope. The doctor read and uttered an exclamation of utter astonishment.

“Impossible,” he muttered. “Impossible.”

“She was one of the original shareholders in Mortaulds. Forty years ago she must have had an income of eight or ten thousand a year. She has never, I am sure, spent more than four hundred a year. She was always terribly careful about money. I always believed that she was obliged to be careful about every penny.”

“And all the time the income has accumulated at compound interest. My dear, you’re going to be a very rich woman.”

Katherine Grey nodded.

“Yes,” she said, “I am.”

She spoke in a detached, impersonal tone, as though she were looking at the situation from outside.