ugh 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."

"What was it?"

"Locked up in the desk in the boudoir, they found a will of Mrs.
Inglethorp's, dated before her marriage, leaving her fortune to Alfred
Inglethorp. It must have been made just at the time they were engaged.
It came quite as a surprise to Wells--and to John Cavendish also. It was
written on one of those printed will forms, and witnessed by two of the
servants--not Dorcas."

"Did Mr. Inglethorp know of it?"

"He says not."

"One might take that with a grain of salt," I remarked sceptically. "All
these wills are very confusing. Tell me, how did those scribbled words
on the envelope help you to discover that a will was made yesterday
afternoon?"

Poirot smiled.

"Mon ami, have you ever, when writing a letter, been arrested by the
fact that you did not know how to spell a certain word?"

"Yes, often. I suppose every one has."

"Exactly. And have you n