And Duson died from a dose of that same poison, a packet of which you procured secretly from Emil Sachs.

An empty wineglass was by his side--it was one generally used by Mr.Sabin.
I know that the English police, who are not so foolish as people would have one believe, are searching now for the woman who was seen to enter the sitting-room shortly before Mr.Sabin returned and found Duson there dead." She laughed scornfully.
"It is ingenious," she admitted, "and perhaps a little unfortunate for me.

But the inference is ridiculous.

What interest had I in the man's death ?" "None, of course!" the Prince said.

"But, Lucille, in all cases of poisoning it is the wife of whom one first thinks!" "The wife?
I did not even know that the creature had a wife." "Of course not! But Duson drank from Mr.Sabin's glass, and you are Mr.Sabin's wife.