“Of course.”

“Well, this is some of the dust.  The woman probably threw the chips out of the window.”

“The woman?”

Coquenil nodded.  “She helped Martinez while he bored the holes.”

Tignol listened in amazement.  “You think Martinez bored those holes?  The man who was murdered?”

“Undoubtedly.  The spirals from the auger blade inside the holes show plainly that the boring was done from Number Six toward Number Seven.  Take the glass and see for yourself.”

Tignol took the glass and studied the hole.  Then he turned, shaking his head.  “You’re a fine detective, M. Paul, but I was a carpenter for six years before I went on the force and I know more about auger holes than you do.  I say you can’t be sure which side of the wall this hole was bored from.  You talk about spirals, but there’s no sense in that.  They’re the same either way.  You might tell by the chipping, but this is hard wood covered with thick enamel, so there’s apt to be no chipping.  Anyhow, there’s none here.  We’ll see on the other side.”

“All right, we’ll see,” consented Coquenil, and they went around into Number Six.

The old man drew back the sofa hangings and exposed two holes exactly like the others—­in fact, the same holes.  “You see,” he went on, “the edges are clean, without a sign of chipping.  There is no more reason to say that these holes were bored this side than from that.”

M. Paul made no reply, but going to the sofa he knelt down by it, and using his glass, proceeded to go over its surface with infinite care.

“Turn up all the lights,” he said.  “That’s better,” and he continued his search.  “Ah!” he cried presently.  “You think there is no reason to say the holes were bored from this side.  I’ll give you a reason.  Take this piece of white paper and make me prints of his boot heels.”  He pointed to the body.  “Take the whole heel carefully, then the other one, get the nail marks, everything.  That’s right.  Now cut out the prints.  Good!  Now look here.  Kneel down.  Take the glass.  There on the yellow satin, by the tail of that silver bird.  Do you see?  Now compare the heel prints.”

Papa Tignol knelt down as directed and examined the sofa seat, which was covered with a piece of Chinese embroidery.

“Sapristi! You’re a magician!” he cried in great excitement.

“No,” replied Coquenil, “it’s perfectly simple.  These holes in the wall are five feet above the floor.  And I’m enough of a carpenter, Papa Tignol,” he smiled, “to know that a man cannot work an auger at that height without standing on something.  And here was the very thing for him to stand on, a sofa just in place.  So, if Martinez bored these holes, he stood on this sofa to do it, and, in that case, the marks of his heels must have remained on the delicate satin.  And here they are.”

“Yes, here they are, nails and all,” admitted Tignol admiringly.  “I’m an old fool, but—­but——­”