"Well, Watson," said Holmes, leaning back in the railway carriage. "What is our next move?"

"I beg your pardon?"

"We have now solved--so far as we know--the mystery of what happened to Julia Stoner alias Whitworth, Helen Armitage nee Stoner, and Dr. Grimesby-Roylott. What we do not yet understand is how your wife came to die of the same symptoms several years later. I, at this moment, cannot think of any more productive course of action than to attempt to determine the name, origin and provenance of the poison Roylott was using. Can you?"

"No, Holmes," I said humbly. "That seems to me much the best way to proceed."

"And have you any thoughts about how to identify this toxin?" Holmes went on.

"You could analyze it in your laboratory, surely?" I said.

"I could," Holmes agreed. "And a month or two later I might have isolated the active chemical agent, but that would not tell us what plant these leaves used to be attached to or where it grows, which is what we need to know if we are to determine how the same poison came to be in the possession both of the late Dr. Roylott and whoever murdered Mary."

I thought for some time, while Holmes lapsed into silence.

"The question is," I finally said, "whether it is really a poison at all."

"It certainly seems to behave like one," Holmes observed dryly.

"What I mean," I replied, "is that almost any drug will become a poison if it is administered improperly. The same medicines we prescribe for heart complaints, for instance, can easily bring on heart failure if the apothecary or the physician makes an honest mistake. What Roylott gave Julia and Helen may be a respected member of the orthodox pharmacopaeia--which he abused for his own evil ends."

"May be," Holmes said, reading my expression, "but probably is not."

"If this drug really is an abortifacient, then as of 1861 it has been illegal," I answered. "If it was ever used by the regular medical profession, it will have been removed from both the dispensaries and the current medical literature before I ever studied medicine; and therefore neither I nor my colleagues would ever have heard of it."

"How do we find out what it is, then?" said Holmes.

"Well," I answered, "I think this is a job that requires a woman's touch."

"What do you mean?"

I leaned forward and lowered my voice.

"Holmes, after the second miscarriage I consulted the most highly respected men I knew who had specialized in obstetrics and gynecology. It is still, as you know, a new discipline; and I hope you will take it in the spirit of a professional confidence when I tell you privately that every form of treatment any one of them proposed appeared to me to be at best utterly worthless and at worst dangerous and barbaric. Mary was willing to try almost anything, but after she had been subjected to a few of the least invasive and harmful treatments I told her that I would not allow any more of my colleagues to experiment upon her. Because that is what medical treatment amounts to, Holmes, in a new field like gynecology. No doctor will tell you this, of course."

"Of course," Holmes sighed, in a way that told me that he could no longer be surprised by anything.

"But we...we wanted children," I said, my voice beginning to waver. "So since medicine had not helped us, we tried everything else."

I was afraid that Holmes would be shocked, but he simply waited to hear what "everything else" meant.

"There is one woman I can think of who might know about this drug, and for whose opinion and truthfulness I have the highest regard," I went on. "But Holmes, you must be aware that half of what she does for a living is quite illegal, and the other half would result in the suspension of her midwifery license if my colleagues ever learned of it. If I bring you there, I am implicitly giving her my word of honor that whatever we learn from her will never reach any of the official authorities."

"Absolutely, Watson," Holmes said, quickly. "Poor Mary is so long dead that it would be no use going through official channels in any case. Whoever the culprit is--if we can identify him--will have to be dealt with outside the law."

Still unsure of what precisely he meant by that, I said, "Then when we get to London, I will ask you to come with me to consult a woman who will only give her name as Lillith. I warn you in advance that she does not hold with the scientific method, and is not overfond of men."

Holmes crossed his arms over his chest, with something like a smile.

"Not overfond, eh?"

"She does not see us at our best, Holmes."

Something in my tone chastened his rising amusement. Still, I could see that old enthusiasm glimmering in his eye.

"Well, Watson," he said. "I had no idea that in this day and age one could still find a wise woman in the heart of London."

"Well, she does live in the western suburbs," I said, with a straight face.

Holmes laughed. "Very well, Watson, I give you my word that I will do my utmost to avoid giving offence. Lead on into the medical underworld, and I will meekly sit back and enjoy the adventure as it unfolds."

The adventure unfolded in the rather damp sitting room of a decaying but respectably kept-up townhouse in a neighborhood that was barely clinging to lower middle class respectability. I believe that Holmes was disappointed to discover that Lillith was no older than forty, and that she was dressed in a quite ordinary woolen frock and had her straw-colored hair done up in a tidy little bun. As Holmes took the seat she offered him, carefully not allowing the slightest vestige of his excitement or amusement to show on his face.

"I'm pleased to see you again, Dr. Watson," Lillith said, taking my hand and shaking it just as if she had been another man. "But I must say I am surprised. You haven't married again, surely?"

"Not quite," I answered, unable to prevent a reflex glance at Holmes, who hid his vexation.

"If it's that kind of trouble," Lillith said, her manner suddenly glacial, "I will only deal with the woman directly, and she must come alone."

"No, no, it is nothing like that," I stammered, much taken aback as I realized what she had assumed. "I am--I mean--I have come here about a professional matter. I need your advice, as--as a colleague."

Her face suddenly brightened. "Ah, well then. That is much more the sort of thing I would expect from you. Mr. Holmes, I presume, can be trusted?"

Urged by some imp within, I said, "Yes, you may speak as freely before him as before myself."

Holmes waited until she had turned to take her chair, and shot me a venomous and yet affectionate glare.

"What can I do for you, Doctor?" Lillith finally said.

I handed her the bag full of dried leaves. "I was wondering if you would recognize this herb at all. I do not, myself, although I believe it may have been used as an abortifacient."

Lillith drew one of the leaves out of the bag, examined it closely, crushed it between her fingers, and sniffed at the dust.

Her expression altered instantly. Holmes leaned forward. We both knew she had recognized it.

"Where did this come from?" Lillith demanded, sharply.

"We were hoping you could tell us," I replied. "Do you know it?"

"I do," she said. "I've been offered the chance to buy it several times, by out of work sailors or soldiers who are selling off their Indian booty. I don't buy it because I don't use it--and neither will any reputable woman in this business."

"What is it?" Holmes demanded.

"Why not?" I asked, at the same time.

Lillith looked from him to me, and decided to answer both of us.

"The plant itself grows naturally in the north of Bengal; but the leaves keep well when dried, and the drug is in general use all over India. The fine young men of our armed forces discover it through the local women, whom they seduce, rape, and otherwise impregnate at what must surely be an alarming rate. It is true that if you dissolve the crushed leaves in hot water and give the liquid to a pregnant woman, her pregnancy will be over in about twenty-four hours. However, in addition to suffering a miscarriage with all its attendant risks, she will also break out in a very unpleasant rash, accompanied by mild fever and nausea."

I nodded. "And that is why you do not use it?"

"That's one reason," Lillith answered, curtly.

"What are the others?" I pressed.

She took a long moment to decide whether she would reveal a professional secret to someone who, warmly as she may have felt toward me, was by virtue of my profession something of a natural enemy.

"The main one," she answered, "is that if you should happen by accident to give this brew to a woman who is not pregnant, it would most likely kill her."

"Ah," said Holmes.

Lillith looked at him. He looked meekly down at the carpet and forbore to comment further.

"And what would happen if it were given to a man?" I asked.

Lillith shrugged. "So far as I know, nothing. It acts upon the womb. I doubt a man who was exposed to it would suffer more than a mild case of theague."

"Have you ever heard of anyone administering it as an inhaled vapour?" Iasked.

"No," she said, surprised. "I suppose it might be possible, but I think steaming it would greatly dilute its impact. And it would be difficult to vapourise the stuff. It makes a kind of milky, viscous solution that is thicker than water."

"Difficult, but not impossible," Holmes murmured.

"No," said Lillith, with a sharp glance in his direction. "Not impossible. Few things are."

"So if you were going to obtain this drug," Holmes said, having now decisively failed at his attempt to sit back and enjoy the adventure, "I suppose it would not be worth applying to you or one of your colleagues, since it has such a sinister reputation?"

"Absolutely not," Lillith said. "There is no reason for us to pay smuggler's prices for a remedy that has potentially fatal consequences when there are indigenous plants that will produce the same result with less danger and suffering."

"But a returning soldier from India--especially one that might have been something of a gay blade, as it were--might have accumulated his own collection?"

"Evidently," Lillith said. "In the past several years they seem to have realized that there is no market for the stuff; I haven't seen it on the black market in over a decade. But before then, you would see it from time to time. Most of the men who approached me about it were or had been officers. I suppose perhaps they have more lesiure time, in which to do more damage."

I stared at the leaves in the bag. Holmes said, "What is the name of the plant?"

"There is a name for it in the native language of the region," she replied. "But we call it 'serpent's tooth.'"

I got to my feet, a little abruptly.

"Thank you, Lillith," I said. "I appreciate your help, and everything that you did for poor Mary."

"I wish I could have helped her," Lillith said, frankly. "She truly wanted children, and I wish I could have made it possible. I have not had the opportunity yet to tell you," she went on, "how sorry I was to read about her death. She was a remarkable woman, and you must miss her terribly."

I missed her so much, at that very moment, that all I could do was press her hand, walk as quickly as possible to the door, while Holmes made our goodbyes.

"I am glad to have met you," Holmes said, as I pushed open the door to the street. "I hope that if I were ever investigating a case where it occurred to me that you might be able to help someone I could not help, you would at least agree to consult with me?"

"Certainly, Mr. Holmes," Lillith answered. "I never pass up the opportunity to help another woman, no matter how it may present itself to me."

"I will keep that in mind," said Holmes. "Thank you for your time."

He joined me out in the street, and began walking with an energy and decision that told me that the balance had shifted again, and he was once more the one who had seen more than I had.

"Where are you going, Holmes?" I cried.

"To find the new heir to Stoke Moran," he said. "I have a few questions I should like to put to him."

"Which are?" I panted, finally catching up with him.

"Time enough when we get there, Watson."