Next morning Quarles called for me.
"We'll go to the stores first," he said. "I have a fancy to look at the items in the list sent. There might be some drug which would make Mrs. Jardine sleep more soundly."
"The list was not sent. I have it here."
"I mean the one sent in place of that," said the professor. "Of course one was sent. People who are not in the habit of having much money in the house would see that the store cupboard was replenished."
He was right. A list was shown to us, and I had some difficulty in not showing signs of excitement. The writing was the same as that on the envelope in Jardine's flat. It was peculiar writing, and I could swear to it.
"I think we shall find that Martha Wakeling wrote that," said Quarles. "If so, we establish a link between her and Jardine which neither of them has mentioned."
"But since she would profit by the crime, why should she communicate with him?"
"We are going to find out," he answered. "I presume you have not been keeping any particular watch upon Martha Wakeling?"
"No."
"Has she mentioned what she intends to do when this affair is over?"