"My dear fellow," I said, "is this wise? Surely you don't want the whole house to know of this occurrence? You are actually playing into the criminal's hands."
"You think so, Hastings?"
"I am sure of it."
"Well, well, my friend, I will be guided by you."
"Good. Although, unfortunately, it is a little too late now."
"Sure."
He looked so crestfallen and abashed that I felt quite sorry, though I still thought my rebuke a just and wise one.
"Well," he said at last, "let us go, mon ami."
"You have finished here?"
"For the moment, yes. You will walk back with me to the village?"
"Willingly."
He picked up his little suit-case, and we went out through the open window in the drawing-room. Cynthia Murdoch was just coming in, and Poirot stood aside to let her pass.
"Excuse me, mademoiselle, one minute."
"Yes?" she turned inquiringly.
"Did you ever make up Mrs. Inglethorp's medicines?"
A slight flush rose in her face, as she answered rather constrainedly: "No."
"Only her powders?"
The flush deepened as Cynthia replied: "Oh, yes, I did make up some sleeping powders for her once."
"These?"
Poirot produced the empty box which had contained powders.
She nodded.
"Can you tell me what they were? Sulphonal? Veronal?"
"No, they were bromide powders."
"Ah! Thank you, mademoiselle; good morning."
As we walked briskly away from the house, I glanced at him more than once. I had often before noticed that, if anything excited him, his eyes turned green like a cat's. They were shining like emeralds now.
"My friend," he broke out at last, "I have a little idea, a very strange, and probably utterly impossible idea. And yet-- it fits in."
I shrugged my shoulders. I privately thought that Poirot was rather too much given to these fantastic ideas. In this case, surely, the truth was only too plain and apparent.
"So that is the explanation of the blank label on the box," I remarked. "Very simple, as you said. I really wonder that I did not think of it myself."
Poirot did not appear to be listening to me.
"They have made one more discovery, la-bas," he observed, jerking his thumb over his shoulder in the direction of Styles. "Mr. Wells told me as we were going upstairs."