"Ah, Watson, come in," he invited, looking up at the sound of my step. "We are having a very productive afternoon."

"And evening, too," I observed. "It's past seven."

"That late? So it is."

"So what has the afternoon produced?" I enquired, settling into my old chair and lighting my own pipe by way of olfactory self-defense against the acrid fog.

"Two cables, one to Boston and one to New York. Miss Smith has almost certainly obtained her scientific education, and probably a bachelor's degree in chemistry, from Tufts University in Boston. Her theory is fair, although it is not her strong point. It is her bench work that is outstanding; she has a butterfly's touch with a burette; you should see it, Watson. We have pulled up a number of memories from her college days in the course of a few little titrations; apparently it was a pleasant period in her life."

"Thus the cable to Boston," I deduced. "You hope to find someone who knows her history."

"Just so."

"And the cable to New York?"

"That is a longer shot. It has to do with her connection with Garnett. She has almost certainly made her living as a chemist; I think she was Garnett's employee. If Garnett's livelihood was in some esoteric branch of medical pharmaceutics (and I have a notion as to just how esoteric), a narrow specialty, and yet had enough business to force him to hire an assistant, it suggests he was operating in a largish population center, and New York is America's commercial capital. It is also its capital of crime. I have a friend in the New York Police Department who will give my inquiry the follow-up it deserves.

"But how, in your theory, did she go from being Garnett's employee to being his prisoner?"

"That I shall allow you to reason out for yourself. Your brain can use the exercise. The other item up for consideration has to do with the story told to Lestrade by our friend Sacker. I smoked a couple of pipes thinking it over, and eventually noticed a curious thing about it. A rather large number of his lies were sprung from truths. Of course, if you're trying to tell a story that is likely to be checked, the closer you parallel actual events the better, but still it was an indication of how his mind worked. Now, in his little play we find these creations: persons born in England who have emigrated; a 'loose screw' who went to South America; a person who, falling in love late in life, allows emotion to overcome reason; and a doctor. Sacker and Garnett are both certainly English, and Garnett is certainly a doctor, apparently between 55 and 60 years old by his description. What about the South American connection?

"It would be too much to expect this old index to contain an account of every Englishman who has left under a cloud for South America in the last 25 years; but a doctor, particularly that rarity, a medical criminal, might be expected to stand out in the crowd. Remember Dr. Grimesby Roylott? Thus."

He handed me the old scrapbook, and pointed out a pair of yellowed clippings.

The first was an account, dated 1881, of a case that had come before the London Assizes alleging a fraudulent collusion between a doctor, one Lewis Brookman, and the heir-at-law of one of his patients. The patient had been an aging textiles entrepreneur, and the issue a false certification of insanity, the purpose being to gain control of the old businessman's estate. It was hinted that the doctor's role went beyond a mere faked document, to the actual creation of symptoms of dementia in his patient by means yet unproved.

The second clipping, a follow-up of the first, reported the case dropped from court due to lack of evidence and suspicions of the validity of the testimony of two of the witnesses. The defendant Dr. Brookman was reported to be considering leaving his ruined London practice for a post at the Hospital San Felice in Rio de Janeiro.

"I do not recall the case," I remarked, handing the book back to its owner.

"Not surprising. I had nothing to do with it professionally at the time, although I followed it in the papers. The case was thrown out upon technicalities, and a lot of disagreements by the medical authorities called to testify. But the personality of the suave Dr. Brookman interested me. He had had a brilliant university career, and had at one time considered specialization in neurological problems. His career would seem to have been well launched, but evidently his expenditures outran his income to the tune of something over-well over-four figures. Why, was not explained. I wish I had some note upon his vices."

"You think this Brookman, then, is Garnett?"

"I think it is an hypothesis worth testing. There is a suggestive similarity in their methods, and the ages fit."

There was a ring at the door downstairs, and the sound of voices carried upward through the hall.

"Lestrade," said Holmes, levering himself up off the floor. "Now what has he found, I wonder."

The familiar features of the inspector appeared around the doorjamb, looking for all the world like a stoat peeking out of its hole.

"Good evening, Mr. Holmes," he said, entering upon my friend's invitation. He had a small suitcase in his hand. "And you too, Dr. Watson. Oh." This last as he caught sight of the occupant of the chemical corner. I could swear a slight flush rose over his features. "Uh, good evening to you too, Ma'am."

Miss Smith smiled a cool, ironic smile, and inclined her head in a kind of regal acknowledgment of his greeting. I could see his embarrassment aroused a little devilishness in her eyes.

"You are having quite a convention, I see," he went on, taking the chair that his host indicated. "No need for you to get up, Dr. Watson. What I came to tell Mr. Holmes properly concerns you too, since I understand this lady is now your patient."

"Have the official police captured their quarry, then?" I asked.

"Well, yes and no," Lestrade replied, rubbing a finger over his cheekbone.

"Meaning they have been found and lost again?" inquired Holmes with a lift of eyebrow.

"Meaning that Ormond Sacker was found this morning in the waiting room of the railway station at Liverpool, sitting on a bench with his legs crossed, his hat pulled down over his eyes, and a newspaper in his lap, stiff as a board. Stone dead," he added.

"Without a mark on him," said Holmes.

Lestrade tried valiantly not to rise to this bait, but failed. "All right. How did you know?"

"Because I know who killed him, and therefore I know how. For the same reason I know that no luggage was found with him."

Lestrade sighed. "I don't suppose you would favor me with the reason why as well, as long as you're about it?"

"Ah, that is another puzzle. At this point the only reasons I could suggest would be guesses, and you know how I abhor guessing."

"At any rate," Lestrade went on, "the autopsy is scheduled for tonight in Liverpool. I wondered if you would care to go along with me and see what there is to be seen."

"Sacker was murdered by the one you call Garnett; the method was poison, and the autopsy will not find it," came a low voice from the chemical corner. We all turned our attention to see Miss Smith, her face in her hands,

in that hunched posture which I now knew to be indicative of the highest tension.

"I hate to sound like an echo of the good inspector," said Holmes quietly, "but how do you know that the autopsy will not find the poison?"

"Because," she said into her hands, "the coroner in New York couldn't find it either."

Holmes smiled a beatific smile. "Ah," he said. "The last piece." He went to her and took her hands gently from her face. "Now, Cordelia, try not to be upset," he said in the same earnest tones he had used to such good effect before, "but I want you to tell me what you recall. Remember, you are safe now."