“The next item of evidence I obtained by dusting the margins of the off-side window with a light powder, which made visible a greasy impression three and a quarter inches long on the sharp corner of the right-hand jamb (right-hand from the inside, I mean).

“And now as to the evidence furnished by the body.  The wound in the skull is behind and above the left ear, is roughly circular, and measures one inch and seven-sixteenths at most, and a ragged scalp-wound runs from it towards the left eye.  On the right cheek is a linear contused wound three and a quarter inches long.  There are no other injuries.

“Our next facts are furnished by this.”  He took up the horn and tapped it with his finger, while the solicitor and Mr. Felton stared at him in speechless wonder.  “You notice it is a left horn, and you remember that it was highly sensitive.  If you put your ear to it while I strain it, you will hear the grating of a fracture in the bony core.  Now look at the pointed end, and you will see several deep scratches running lengthwise, and where those scratches end the diameter of the horn is, as you see by this calliper-gauge, one inch and seven-sixteenths.  Covering the scratches is a dry blood-stain, and at the extreme tip is a small mass of a dried substance which Dr. Jervis and I have examined with the microscope and are satisfied is brain tissue.”

“Good God!” exclaimed Stopford eagerly.  “Do you mean to say—­”

“Let us finish with the facts, Mr. Stopford,” Thorndyke interrupted.  “Now, if you look closely at that blood-stain, you will see a short piece of hair stuck to the horn, and through this lens you can make out the root-bulb.  It is a golden hair, you notice, but near the root it is black, and our calliper-gauge shows us that the black portion is fourteen sixty-fourths of an inch long.  Now, in this envelope are some hairs that I removed from the dead woman’s head.  They also are golden hairs, black at the roots, and when I measure the black portion I find it to be fourteen sixty-fourths of an inch long.  Then, finally, there is this.”

He turned the horn over, and pointed to a small patch of dried blood.  Embedded in it was a blue sequin.

Mr. Stopford and the butcher both gazed at the horn in silent amazement; then the former drew a deep breath and looked up at Thorndyke.

“No doubt,” said he, “you can explain this mystery, but for my part I am utterly bewildered, though you are filling me with hope.”

“And yet the matter is quite simple,” returned Thorndyke, “even with these few facts before us, which are only a selection from the body of evidence in our possession.  But I will state my theory, and you shall judge.”  He rapidly sketched a rough plan on a sheet of paper, and continued:  “These were the conditions when the train was approaching Woldhurst:  Here was the passenger-coach, here was the burning rick, and here was a cattle-truck.  This steer was in that truck.  Now my hypothesis