“Suspicions aren’t evidence,” said the Assistant Commissioner shortly. “Bring home the original murders to him by all means and then perhaps you’ll be able to link him up with the death of this man Martin. At present, so far as I can see, you’ll find it difficult to convince a jury that Martin was murdered. That poison-bomb theory is a bit far-fetched, you must admit.” “It is, rather, sir,” agreed Whyland. “Still we’ve got the letter and the numbered counter——” “It’s just that letter that worries me,” interrupted the Chief. “It was through the letter that you discovered that Martin was a receiver of stolen goods—a very smart piece of work, Whyland, upon which I congratulate you. But, until we have rounded them all up, we don’t want the gentlemen with whom Martin dealt to become aware of our knowledge. If the existence of that letter becomes known, they’ll tumble to it at once. I should very much prefer the letter to be kept secret, for the present, at all events.” The Assistant Commissioner paused, and Whyland glanced at him quickly. “I see no reason why it should be mentioned at the inquest, sir,” he said. “Nobody knows of its existence outside of the police.” “Then I should be inclined to say nothing about it,” remarked the Assistant Commissioner. “Nor, I imagine, will it be necessary to bring into prominence the hypothesis of the poison-bomb, or the fact that you have any suspicions of foul play. I am not suggesting that you should wilfully mislead the coroner, mind. But it is usually a mistake to volunteer information when no useful purpose can be served by so doing.” So it happened that the doctor’s evidence at the inquest remain unchallenged. The theory was that Martin, having decided to take his own life, was attracted to his old premises knowing them to be empty. In order to obtain access, he telephoned himself from Aldersgate station to Mr. Briggs, using Mr. Lacey’s name. Having thus secured the key, he bolted the door behind him to prevent any interruption, then went into the cellar and inhaled the vapour of prussic acid. The automatic he had brought with him in the case the poison should prove ineffective. The numbered counter, which he had also brought with him, as the finger-marks upon it showed, merely emphasized the morbid state of mind which had prompted him to the deed.