"Still--I do not see--" I began.
"Neither do I see. I tell you, mon ami, it puzzles me. Me --Hercule Poirot!"
"But if you believe him innocent, how do you explain his buying the strychnine?"
"Very simply. He did not buy it."
"But Mace recognized him!"
"I beg your pardon, he saw a man with a black beard like Mr. Inglethorp's, and wearing glasses like Mr. Inglethorp, and dressed in Mr. Inglethorp's rather noticeable clothes. He could not recognize a man whom he had probably only seen in the distance, since, you remember, he himself had only been in the village a fortnight, and Mrs. Inglethorp dealt principally with Coot's in Tadminster."
"Then you think----"
"Mon ami, do you remember the two points I laid stress upon? Leave the first one for the moment, what was the second?"
"The important fact that Alfred Inglethorp wears peculiar clothes, has a black beard, and uses glasses," I quoted.
"Exactly. Now suppose anyone wished to pass himself off as John or Lawrence Cavendish. Would it be easy?"
"No," I said thoughtfully. "Of course an actor----"
But Poirot cut me short ruthlessly.
"And why would it not be easy? I will tell you, my friend: Because they are both clean-shaven men. To make up successfully as one of these two in broad daylight, it would need an actor of genius, and a certain initial facial resemblance. But in the case of Alfred Inglethorp, all that is changed. His clothes, his beard, the glasses which hide his eyes--those are the salient points about his personal appearance. Now, what is the first instinct of the criminal? To divert suspicion from himself, is it not so? And how can he best do that? By throwing it on some one else. In this instance, there was a man ready to his hand. Everybody was predisposed to believe in Mr. Inglethorp's guilt. It was a foregone conclusion that he would be suspected; but, to make it a sure thing there must be tangible proof--such as the actual buying of the poison, and that, with a man of the peculiar appearance of Mr. Inglethorp, was not difficult. Remember, this young Mace had never actually spoken to Mr. Inglethorp. How should he doubt that the man in his clothes, with his beard and his glasses, was not Alfred Inglethorp?"
"It may be so," I said, fascinated by Poirot's eloquence. "But, if that was the case, why does he not say where he was at six o'clock on Monday evening?"