Nella motioned to the register, urging me to finish the page. “Nerve-root is quite effective,” she said, “though the truth about her son and his plot would have been the best remedy. Alas, I don’t know if her daughter revealed it. No matter, her secret is safe in here.” She ran her finger along the edge of the book, toying with the pages.

I understood, now, why Nella sold medicines in addition to her poisons. People like Ms. Bechem needed both.

Except I still did not know why Nella sold poisons at all. During my first visit to her shop, she’d said the hidden room didn’t exist when she’d worked at the shop as a child with her mother. Why did Nella build the secret room and begin to brew terrible things behind it? I resolved to find the courage to ask her, and soon.

After I finished the entry, Nella flipped the pages again, landing on 1789. The year stood out in my memory; it was the year my mother had left me in London to work for the Amwell family. Only, the entries on this page appeared in good condition. I could not see any that needed work.

“Why, this was just before I arrived in London,” I offered.

“I think you might like this page,” Nella replied. “There is a name on here you should recognize.”

At once, it became a game. I scanned my eyes over the entries, doing my best to ignore the dates and ingredients, searching instead for a name I knew. My own mother, perhaps?

Then I saw it: Mrs. Amwell.

“Oh!” I gasped. “My mistress!” Quickly, I read the rest of the entry. Had my mistress poisoned someone once before? “Indian hemp?” I asked Nella, pointing to the register.

“One of the most powerful drugs in my shop,” she said, “but like the nerve-root, there is nothing harmful about it. Indian hemp is especially useful in the case of tremors or spasms.” She looked at me, waiting. When I did not respond, she explained, “Eliza, your mistress came to my shop when the shaking in her hands first began. I’d forgotten about her visit, until you mentioned earlier today that you write her letters for her.” She ran her fingers over the entry, a faraway look in her eyes. “The gentlemen’s doctors could do nothing for her. She’d paid visits to a dozen of them. She came to me when she felt she had no options left.” She briefly set her hand over mine. “Your mistress had never been here before. She only knew of it from a friend.”

A sense of overwhelming sadness fell over me. I’d never considered that Mrs. Amwell had sought help from so many doctors. I’d never considered at all how she felt about her impediment.

“Did the Indian hemp help?” I asked, glancing again at the entry to ensure I repeated the words correctly.