A point of light, falling through the shattered panel of the closed door, pierced the vague gloom of the passage and hovered on the door of the bedroom opposite—­the room into which the dead man had been carried.

Barrant entered the study and looked around him.  It was intolerably dirty and neglected; everything was covered with a thick grey dust.  Barrant walked over to the clock and regarded it attentively.

What a rascally fat face that moon had!  It must have seen some queer sights in old houses during its two hundred years of life.  Strange that those old clockmakers could make clocks to last so long, but couldn’t keep their own life-springs running half the time!  The moral verse was curious enough.  Why should a man who spent half his lifetime putting together a clock presume to tell his fellow creatures to make the most of the passing hour?

His reflections took a more practical turn.  The clock was the sole witness to the time of the murder.  There were two other clocks in Flint House, but nobody had thought of looking at them when the crime was discovered.  Barrant regarded that as a regrettable oversight.  It was always important to know the exact time when a murder was committed.  Thalassa said that the hood clock was going and kept excellent time, but the value of that secondary testimony was impaired by the fact that Thalassa might not be telling the truth.  On the other hand, there was certain presumptive evidence which suggested that he was.  It was a proved fact that Mr. and Mrs. Pendleton and Dr. Ravenshaw left the doctor’s house in a motor-car for Flint House not later than half-past nine on the night of the murder.  Assuming that they covered the journey across the moors in five or six minutes and occupied another five minutes in getting upstairs and breaking in the door, the testimony of the hood clock seemed correct, because Dr. Ravenshaw said death had just taken place, and he and the doctor who made the post-mortem examination were both agreed that Robert Turold could not have lived many minutes after he was shot.  Therefore the presumptive evidence seemed to determine the time of death accurately enough.

But that was only a minor phase of the mystery.  The real problem was the hidden connection between the clock and the murder.  What had brought the clock down, and why had Robert Turold fallen almost on top of it, his outstretched hands resting on the dial?  The complete elucidation of the mystery lay behind the obscurity in which these two points were shrouded.  To find the answer to them was the surest and quickest way of reconciling all the contradictory facts of the case.  But Barrant racked his brains for the reason in vain.