“You need not tell me anything you do not want to.”

She sat back in her chair and said in her natural voice,

“Well then, if you must know, I had posted it. That’s what gave me such a turn.”

“You had posted a letter of which a fragment was found on your bedroom floor?”

“Well, yes, I had. And that is what upset me.”

“Dear me!” said Miss Silver. “You wrote a letter and you posted it, and afterwards a piece of that letter was found lying under your window.”

“That’s right.”

“Did you post the letter yourself, or did you give it to your maid?”

“Oh, no-I posted it myself, with my own hand.”

“Did you make more than one copy of the letter?”

Mrs. Underwood shook her head.

“It was as much as I could do to write it once.”

Miss Silver knitted. After a moment she said,

“Your letter was in reply to one from a person who is, or has been, blackmailing you. Do you know who this person is?”

The head with its tinted chestnut curls was shaken again. The mauvish colour rose.

“I haven’t an idea. There isn’t anyone I can think of. There was an address, so I went to have a look-right the other side of London, but I went. And when I got there, it was nothing but a tobacconist’s shop, and they said a lot of their customers called for their letters there, and made out it was all on account of people being bombed out-and I didn’t believe a word of it, but they wouldn’t tell me anything. So I posted my letter at the end of the street and came away.”

“You posted that letter on the other side of London?”

Mrs. Underwood nodded.

“Yes, I did. And that’s what gave me the turn, because how did it get back into Vandeleur House, and how did that Ivy Lord come by a piece of it to drop in my room? Because that’s what she must have done.