“Why did you leave the lid open?” I asked. “Did you forget?”

“I was startled,” said Mrs. Ackroyd. “I heard footsteps coming along the terrace outside. I hastened out of the room and just got up the stairs before Parker opened the front door to you.”

“That must have been Miss Russell,” I said thoughtfully.

Mrs. Ackroyd had revealed to me one fact that was extremely interesting. Whether her designs upon Ackroyd’s silver had been strictly honourable I neither knew nor cared. What did interest me was the fact that Miss Russell must have entered the drawing room by the window, and that I had not been wrong when I judged her to be out of breath with running. Where had she been? I thought of the summerhouse and the scrap of cambric.

“I wonder if Miss Russell has had her handkerchiefs starched!” I exclaimed on the spur of the moment.