It was more than an hour later when Vance entered the District Attorney’s office, where Markham and Heath and I were waiting. He glanced quickly round the room and then looked at our faces.
“I told you to watch her, Sergeant,” he said, sinking into a chair; but there was neither reproach nor regret in his voice.
None of us spoke. Despite the effect Ada’s suicide had had on us, we were waiting, with a kind of conscience-stricken anxiety, for news of the other girl whom all of us, I think, had vaguely suspected.
Vance understood our silence, and nodded reassuringly.
“Sibella’s all right. I took her to the Trinity Hospital in Yonkers. A slight concussion—Ada had struck her with a box-wrench which was always kept under the front seat. She’ll be out in a few days. I registered her at the hospital as Mrs. Von Blon, and then phoned her husband. I caught him at home, and he hurried out. He’s with her now. Incidentally, the reason we didn’t reach him at Mrs. Riglander’s is because he stopped at the office for his medicine-case. That delay saved Sibella’s life. Otherwise, I doubt if we’d have reached her before Ada had run her over the precipice in the machine.”
He drew deeply on his cigarette for a moment. Then he lifted his eyebrows to Markham.
“Cyanide of potassium?”
Markham gave a slight start.
“Yes—or so the doctor thinks. There was a bitter-almond odor on her lips.” He shot his head forward angrily. “But if you knew—”
“Oh, I wouldn’t have stopped it in any case,” interrupted Vance. “I discharged my wholly mythical duty to the State when I warned the Sergeant. However, I didn’t know at the time. Von Blon just gave me the information. When I told him what had happened I asked him if he had ever lost any other poisons—you see, I couldn’t imagine anyone planning so devilish and hazardous an exploit as the Greene murders without preparing for the eventuality of failure. He told me he’d missed a tablet of cyanide from his darkroom about three months ago. And when I jogged his memory he recalled that Ada had been poking round there and asking questions a few days before. The one cyanide tablet was probably all she dared take at the time; so she kept it for herself in case of an emergency.”29
“What I want to know, Mr. Vance,” said Heath, “is how she worked this scheme. Was there anyone else in on the deal?”
“No, Sergeant. Ada planned and executed every part of it.”
“But how, in God’s name—?”
Vance held up his hand.
“It’s all very simple, Sergeant—once you have the key. What misled us was the fiendish cleverness and audacity of the plot. But there’s no longer any need to speculate about it. I have a printed and bound explanation of everything that happened. And it’s not a fictional or speculative explanation. It’s actual criminal history, garnered and recorded by the greatest expert on the subject the world has yet known—Doctor Hans Gross, of Vienna.”
He rose and took up his coat.
“I phoned Currie from the hospital, and he has a belated dinner waiting for all of us. When we have eaten, I’ll present you with a reconstruction and exposition of the entire case.”
XXVI
The Astounding Truth
(Monday, December 13; 11 p.m.)
“As you know, Markham,” Vance began, when we were seated about the library fire late that night, “I finally succeeded in putting together the items of my summary in such a way that I could see plainly who the murderer was.30 Once I had found the basic pattern, every detail fitted perfectly into a plastic whole. The technic of the crimes, however, remained obscure; so I asked you to send for the books in Tobias’s library—I was sure they would tell me what I wanted to know. First, I went through Gross’s Handbuch für Untersuchungsrichter, which I regarded as the most likely source of information. It is an amazing treatise, Markham. It covers the entire field of the history and science of crime; and, in addition, is a compendium of criminal technic, citing specific cases and containing detailed explanations and diagrams. Small wonder it is the world’s standard cyclopaedia on its subject. As I read it, I found what I was looking for. Ada had copied every act of hers, every method, every device, every detail, from its pages—from actual criminal history! We are hardly to be blamed for our inability to combat her schemes; for it was not she alone who was deceiving us; it was the accumulated experience of hundreds of shrewd criminals before her, plus the analytic science of the world’s greatest criminologist—Doctor Hans Gross.”
He paused to light another cigarette.
“But even when I had found the explanation of her crimes,” he continued, “I felt that there was something lacking, some fundamental penchant—the thing that made this orgy of horror possible and gave viability, so to speak, to her operations. We knew nothing of Ada’s early life or of her progenitors and inherited instincts; and without that knowledge the crimes, despite their clear logic, were incredible. Consequently, my next step was to verify Ada’s psychological and environmental sources. I had had a suspicion from the first that she was Frau Mannheim’s daughter. But even when I verified this fact I couldn’t see its bearing on the case. It was obvious, from our interview with Frau Mannheim, that Tobias and her husband had been in shady deals together in the old days; and she later admitted to me that her husband had died thirteen years ago, in October, at New Orleans after a year’s illness in a hospital. She also said, as you may recall, that she had seen Tobias a year prior to her
