Scientific explanations also were to hand to explain how the assassin locked and bolted the door behind him.  Powerful magnets outside the door had been used to turn the key and push the bolt within.  Murderers armed with magnets loomed on the popular imagination like a new microbe.  There was only one defect in this ingenious theory—­the thing could not be done.  A physiologist recalled the conjurers who swallow swords—­by an anatomical peculiarity of the throat—­and said that the deceased might have swallowed the weapon after cutting his own throat.  This was too much for the public to swallow.  As for the idea that the suicide had been effected with a penknife or its blade, or a bit of steel, which had then got buried in the wound, not even the quotation of Shelley’s line:—­

  “Makes such a wound, the knife is lost in it,”

could secure it a moment’s acceptance.  The same reception was accorded to the idea that the cut had been made with a candle-stick (or other harmless necessary bedroom article) constructed like a sword stick.  Theories of this sort caused a humorist to explain that the deceased had hidden the razor in his hollow tooth!  Some kind friend of Messrs. Maskelyne and Cook suggested that they were the only persons who could have done the deed, as no one else could get out of a locked cabinet.  But perhaps the most brilliant of these flashes of false fire was the facetious, yet probably half-seriously meant letter that appeared in the Pell Mell Press under the heading of

  “THE BIG BOW MYSTERY SOLVED

“Sir,—­You will remember that when the Whitechapel murders were agitating the universe, I suggested that the district coroner was the assassin.  My suggestion has been disregarded.  The coroner is still at large.  So is the Whitechapel murderer.  Perhaps this suggestive coincidence will incline the authorities to pay more attention to me this time.  The problem seems to be this.  The deceased could not have cut his own throat.  The deceased could not have had his throat cut for him.  As one of the two must have happened, this is obvious nonsense.  As this is obvious nonsense I am justified in disbelieving it.  As this obvious nonsense was primarily put in circulation by Mrs. Drabdump and Mr. Grodman, I am justified in disbelieving them.  In short, sir, what guarantee have we that the whole tale is not a cock-and-bull story, invented by the two persons who first found the body?  What proof is there that the deed was not done by these persons themselves, who then went to work to smash the door and break the locks and the bolts, and fasten up all the windows before they called the police in?—­I enclose my card, and am, sir, yours truly,

  “ONE WHO LOOKS THROUGH HIS OWN SPECTACLES.”

“[Our correspondent’s theory is not so audaciously original as he seems to imagine.  Has he not looked through the spectacles of the people who persistently suggested that the Whitechapel murderer was invariably the policeman who found the body? Somebody must find the body, if it is to be found at all.—­Ed. P.M.P.]”