“Well, if it was not an attempt at murder, what was it?”

“Suicide!  It’s as plain as the nose on your face.  Shirley was passing us as we were standing with Millard and as you told Millard we all were to go to the projection room to identify the criminal.  Therefore Shirley knew he was at the end of his rope.  With the theatrical temperament, he took the poison just as he finished playing his last great scene.  It—­it was a sort of swan song.”

“Quite a theory, Walter!” Now I knew Kennedy was unimpressed.  “But, where did he get the belladonna?”

“For his eyes.  After the smoke smart.”

“The drug is of no use against such inflammation.”

“No, but it served to brighten his eyes.  Enid suggested it to him and he went out and got it.  It helped him play his scenes.  It gave him the glittering expression he needed in his characterization.”

Again Kennedy seemed to grasp my view.  He hesitated for several moments.  Finally he looked up.

“If Shirley is the criminal, and if he is above using as common a drug as atropin for killing another man, then—­then why isn’t he above using it upon himself?”

That struck me as easy to answer.  “Because if he is killing himself it is not necessary for him to cover his tracks, or to do it cleverly, and besides”—­it was my big point—­“he probably didn’t decide to try to do it until he overheard us and realized the menace.  At that time he had the belladonna in his pocket.  He did not have an opportunity to procure anything else.”

Kennedy grinned.  “You’re all wrong, Walter, and I’ll show you where your reasoning is faulty.  In the first place if this criminal was the type to commit suicide at the moment he thought he was about to be caught he would be the type who would reflect upon that idea beforehand.  As his crimes show a great deal of previous preparation, so we may assume that he would prepare for suicide, or rather for the possibility that he might wish to attempt it.  Therefore he would have something better for that purpose than atropin.”

I shook my head, but Kennedy continued.

“As a matter of fact, the use of that drug is not less clever than the use of the venom or the toxin; it is more so.  Stop and think a minute!  The snake venom was employed in the case of Miss Lamar’s death because it offered about the least possible chance of leaving telltale clues behind.  The snake poison could be inflicted with a tiny scratch, and in such a way that an outcry from the girl would never be noticed.  Nothing but my pocket lens caught the scratch; only the great care I used in my examination put us on the trail at all.

“Now remember how Werner met his death.  The toxin gave every symptom of food poisoning.  Except that we discovered the broken stem of the wineglass we would never have been able to prove the tragedy anything but accident.  Very possibly we have Shirley to thank for the fact that our one clue there was not removed or destroyed.