The facts were there, but they were inexplicable, or at least they stared at him with the aspect of many faces.
As he weighed these doubts he found his thoughts reverting with increasing frequency to the hood clock in Robert Turold's study and the question of its connection with the crime.

He pondered over the point with the nervous anxiety of a puzzled brain, and it seemed to him now that he had not devoted as much investigation to this peculiar clue as it deserved.

He recalled Mr.Brimsdown's conversation on the matter.

He remembered that he had been struck at the time by the penetration of his remarks about the clock, and while not accepting his fantastic theory, had determined to give more careful thought to the point.

But Mrs.Brierly's disclosure put the idea out of his head.
It recurred to him with renewed force when he found himself in Exeter nearly a fortnight later on another case.