“One thing at a time. As to the sleeping powders, I knew by this.” He suddenly produced a small cardboard box, such as chemists use for powders.

“Where did you find it?”

“In the washstand drawer in Mrs. Inglethorp’s bedroom. It was Number Six of my catalogue.”

“But I suppose, as the last powder was taken two days ago, it is not of much importance?”

“Probably not, but do you notice anything that strikes you as peculiar about this box?”

I examined it closely.

“No, I can’t say that I do.”

“Look at the label.”