Two facts had sharply demonstrated themselves:  first, that Mr. Shackford had been murdered; and, second, that the spur to the crime had been the possession of a sum of money, which the deceased was supposed to keep in a strong-box in his bedroom.  The padlock had been wrenched open, and the less valuable contents of the chest, chiefly papers, scattered over the carpet.  A memorandum among the papers seemed to specify the respective sums in notes and gold that had been deposited in the box.  A document of some kind had been torn into minute pieces and thrown into the waste-basket.  On close scrutiny a word or two here and there revealed the fact that the document was of a legal character.  The fragments were put into an envelope and given in charge of Mr. Shackford’s lawyer, who placed seals on that and on the drawers of an escritoire which stood in the corner and contained other manuscript.

The instrument with which the fatal blow had been dealt—­for the autopsy showed that there had been but one blow—­was not only not discoverable, but the fashion of it defied conjecture.  The shape of the wound did not indicate the use of any implement known to the jurors, several of whom were skilled machinists.  The wound was an inch and three quarters in length and very deep at the extremities; in the middle in scarcely penetrated to the cranium.  So peculiar a cut could not have been produced with the claw part of a hammer, because the claw is always curved, and the incision was straight.  A flat claw, such as is used in opening packing-cases, was suggested.  A collection of the several sizes manufactured was procured, but none corresponded with the wound; they were either too wide or too narrow.  Moreover, the cut was as thin as the blade of a case-knife.

“That was never done by any tool in these parts,” declared Stevens, the foreman of the finishing shop at Slocum’s.

The assassin or assassins had entered by the scullery door, the simple fastening of which, a hook and staple, had been broken.  There were footprints in the soft clay path leading from the side gate to the stone step; but Mary Hennessey had so confused and obliterated the outlines that now it was impossible accurately to measure them.  A half-burned match was found under the sink,—­evidently thrown there by the burglars.  It was of a kind known as the safety-match, which can be ignited only by friction on a strip of chemically prepared paper glued to the box.  As no box of this description was discovered, and as all the other matches in the house were of a different make, the charred splinter was preserved.  The most minute examination failed to show more than this.  The last time Mr. Shackford had been seen alive was at six o’clock the previous evening.

Who had done the deed?