a man had been arrested in Germany charged with stealing a government bond.  He was not searched till later.  There was no evidence save that after the arrest a large number of spitballs were found around the courtyard under his cell window.  This method of comparing the fibres with those of the regular government paper was used, and by it the man was convicted of stealing the bond.  I think it is almost unnecessary to add that in the present case we know precisely who—­”

At this point the tension was so great that it snapped.  Miss La Neige, who was sitting beside me, had been leaning forward involuntarily.  Almost as if the words were wrung from her she whispered hoarsely:  “They put me up to doing it; I didn’t want to.  But the affair had gone too far.  I couldn’t see him lost before my very eyes.  I didn’t want her to get him.  The quickest way out was to tell the whole story to Mr. Parker and stop it.  It was the only way I could think to stop this thing between another man’s wife and the man I loved better than my own husband.  God knows, Professor Kennedy, that was all—­”

“Calm yourself, madame,” interrupted Kennedy soothingly.  “Calm yourself.  What’s done is done.  The truth must come out.  Be calm.  Now,” he continued, after the first storm of remorse had spent itself and we were all outwardly composed again, “we have said nothing whatever of the most mysterious feature of the case, the firing of the shot.  The murderer could have thrust the weapon into the pocket or the folds of this coat”—­here he drew forth the automobile coat and held it aloft, displaying the bullet hole—­“and he or she (I will not say which) could have discharged the pistol unseen.  By removing and secreting the weapon afterward one very important piece of evidence would be suppressed.  This person could have used such a cartridge as I have here, made with smokeless powder, and the coat would have concealed the flash of the shot very effectively.  There would have been no smoke.  But neither this coat nor even a heavy blanket would have deadened the report of the shot.

“What are we to think of that?  Only one thing.  I have often wondered why the thing wasn’t done before.  In fact I have been waiting for it to occur.  There is an invention that makes it almost possible to strike a man down with impunity in broad daylight in any place where there is sufficient noise to cover up a click, a slight ‘Pouf!’ and the whir of the bullet in the air.

“I refer to this little device of a Hartford inventor.  I place it over the muzzle of the thirty-two-calibre revolver I have so far been using—­so.  Now, Mr. Jameson, if you will sit at that typewriter over there and write—­anything so long as you keep the keys clicking.  The inspector will start that imitation stock-ticker in the corner.  Now we are ready.  I cover the pistol with a cloth.  I defy anyone in this room to tell me the exact moment when I discharged the pistol.  I could have shot any of you, and an outsider not in the secret would never have thought that I was the culprit.  To a certain extent I have reproduced the conditions under which this shooting occurred.