prologue

Paris, 1794

The square was filled with people who had woken up at dawn to see blood. They surrounded the wooden stage where the guillotine had been built, elbowing one another and pressing their bodies forward, each person trying to get as close to the action as possible. Those lucky few who had managed to get to the front of the crowd waved handkerchiefs—when the heads began to roll, they would try to dip the handkerchiefs in the blood. Souvenirs. An heirloom they could pass on to their children, and their children’s children. See? I was there, they would say, unfolding the bit of cloth. I saw the Revolution. I saw the traitors lose their heads.

The morning sunlight reflected off the white stone of the courthouse. Even though his hands were bound, Antoine Lavoisier managed to fix the cuffs of his shirt. He had worn his plainest work shirt to court that morning, a simple flax-colored thing; it was what he wore in his laboratory, knowing that it might get stained with sweat or one of the hundreds of chemical solutions he kept in glass vials. His wife, Marie-Anne, had threatened to throw it out a dozen times. Antoine had worn it today, hoping to prove to the judge and the braying crowd outside that he was a man of the people. For all the good it did, he might have worn silk brocade.

Please, he had told the judge. (That cursed word had almost caught in his throat; if the circumstance hadn’t been quite so dire, his nature would have made it impossible to beg.) Please, he repeated, "France needs my work. Imagine what I can do for the nation—for the Republic—if I have more time to continue my scientific studies. I’ve already achieved so much in the study of oxygen. Of hydrogen, the science of combustion! At least let me return to my apartment to organize my paperwork. There are years of calculations. The possibilities for—"

The judge interrupted with a hacking, phlegmy cough. Enough, he said. The Republic needs neither scholars nor chemists who have stolen from the people. And the course of justice cannot be delayed any further. He struck his desk with a gavel. Guilty.

Lavoisier sighed. Pity, he murmured to himself, too softly to be heard above the shouts and jeers from the gleeful crowd. Officially, Antoine Lavoisier had been charged with tax fraud and with selling unsuitable tobacco, swindling the common people by adding water to weigh it down. But he knew as well as anyone that he was really on trial for something else: being an aristocrat and an academic. For having spent the previous decade of his life with his wife, holding salons in their apartment with intellectuals and artists, events where Marie-Anne served tea and repartee and biscuits made by their servants.

France was changing, had changed, faster than Lavoisier had believed possible. There was a bloodlust in the air, a frenzy for something that was called justice but looked like cruelty. Half a dozen of his friends had already lost their heads over meaningless criminal charges that appeared in the middle of the night. The rest of his friends fled to London or Italy. The Lavoisiers had had their chance, too, to run away to England, but they weren’t able to leave their experiments. Their laboratory. They were so close.

Now it was too late.

Just a few months ago, Lavoisier watched as the queen herself was taken through the streets of Paris on the back of a cart, transported like so much lumber in an open cage so that loyal citizens of the Republic could see her face, could throw their rotting fruit and cabbages at her. Lavoisier had to force himself to look; the last time he had seen the queen, he had been a guest at Versailles, demonstrating a new form of chemical combustion for King Louis and his court. The queen had been wearing yellow satin, and her hair was powdered and teased a meter high, dotted with ostrich feathers and pearls. She had been laughing, he remembered that. She laughed when he’d made the small explosions—the smoke first blue, and then green, and then purple, meant to dazzle and amuse. Her face was young and her cheeks had high color.

The day they took the queen to the guillotine, Lavoisier saw that her face was drawn and lined. She looked like a woman decades older than she really was. Her hair had gone stark white and so thin that he could see her scalp in places. Her eyes, Lavoisier observed as the cart passed, were empty and blank. It was as if she had died already, a long time ago.

A guard with a bayonet pulled Lavoisier toward the stage. Some of the onlookers tried to trip him, or get in a blow as he walked past, but Lavoisier barely noticed, so focused was he was on scanning the thousands of faces for his wife, Marie-Anne.

There! he shouted.

The sun lit her from behind, her hair giving her a golden halo. She stood near the wooden steps of the platform, her eyes determinedly scanning the crowd, and her mouth straight and tight. The guard looked back at Lavoisier in confusion, not sure what he had shouted about.

Just then, Marie-Anne saw her husband, and she started swimming her way against the current of bodies to get to him.

The guard jostled Lavoisier, trying to force him along.

He resisted. Surely the Republic’s justice can wait long enough for me to kiss my wife farewell?

The guard sighed but paused and let the pair embrace. Marie-Anne whispered in her husband’s ear. No one noticed her pressing a small vial into his palm.

The guillotine’s blade was brown with blood. There had already been two beheadings that morning, and the straw onstage was matted and red. Someone held a basket, ready to catch Lavoisier’s head when it tumbled from his neck. Others held their white handkerchiefs aloft, hoping for blood splatter.

Marie-Anne Lavoisier didn’t watch her husband ascend the small wooden steps onto the stage. She didn’t want to know if he would shake, or if his legs might give out beneath him. There were even some stories of the condemned soiling themselves.

And so instead, she moved briskly through the crowd, away from the center of the square, toward their apartment, where she would gather as much of her husband’s research material as she could before the vultures came to scavenge whatever valuables they could claim. The new regime was seizing everything it could. Marie-Anne comforted herself with the notion that no matter who stole her husband’s papers, they almost certainly wouldn’t understand them.

She ducked down a small alley. Her footsteps were swift and sure. The crowd behind her inhaled in excitement. Words were shouted that she couldn’t make out. And then there came the unmistakable sound of a blade cutting through the air. Marie-Anne Lavoisier said a quick prayer for her husband, and for her country, and continued on.

1

Edinburgh, 1818

This is going to hurt. I am sorry about that. Hazel Sinnett didn’t feel as though there was any use in lying.

The boy bit down harder on the piece of leather she had brought for that very purpose and nodded. A young girl had come to Hazel’s door the night before and begged her to come, describing the way her older brother’s arm had broken weeks before, while he was working at the shipyard, and the way it had healed wrong: twisted and impossible to move. When Hazel arrived at their dingy flat near Mary King’s Close first thing in the morning, she had found the boy’s arm swollen and hot, the skin bruised yellow and green, and tight as a sausage casing.

Hazel prepared her equipment: a scalpel to cut open the arm and let out the worst of the infection, the needle and thread she would use to sew his arm back up, and then the strips of cloth and pieces of wood she would fashion into something to keep his arm in place once she re-broke and reset it. That last part was going to hurt the most.

The patient was named Martin Potter, and he might have been around her age—sixteen or seventeen maybe—but his face was already browned and set like an adult’s. Hazel imagined that he had been working the docks at Leith since he was ten.

"It’s Martin, isn’t it? I’m Hazel. Dr. Sinnett. Miss Sinnett, she said. And I’m going to do everything I can to make this better."

Martin nodded with a gesture so small it might have been a shiver.

The sound of children laughing and stomping upstairs disrupted the tense, nervous silence. Martin removed the leather strip from his mouth. My brothers and sisters, he said almost apologetically. There are eight of us but I’m the oldest. You would have met Rose already. She’s the one that came to fetch ye. She heard there was a lady doctor who didn’t take much in terms of payment.

Eight siblings! Your poor mother, Hazel said. There are only three of us. Me and my two brothers.

Hazel realized what she had said even before the words had fully left her mouth. There had been three of them: George, Hazel, and little Percy. George, the golden child, athletic and strong, smarter than Hazel and genuinely kind; Hazel, who always found a new way for her mother to criticize her; and Percy, the spoiled princeling who had basically all but become their mother’s poodle.

But there weren’t three of them. Not anymore. George had died a few years ago, when the Roman fever swept through the city, one of thousands who perished before they even understood what the sickness was. He had been so young, so strong, so healthy that even when he first got sick, Hazel remembered wondering whether he’d be well enough for ninepins on the lawn that very weekend or whether she’d have to wait another week for him to get his energy back. But then, quick as the sickness came, it took him. One morning, Hazel woke to the sound of their mother shrieking in heaving sobs. And George was cold.

Her throat used to tighten whenever she thought of George. She would need to turn away and take deep breaths to stave off the tears that came prickling at her eyes. But in the years since, his memory had become like scar tissue, healed over again and again until it was shiny and smooth to the touch, and almost never hurt. Permanent, but the pain wasn’t so sharp. Jack’s death was still an open wound. She couldn’t think of Jack now. Not while she was working.

Are you ready? Hazel asked. Martin’s arm, swollen and askew, was more than distraction enough. Hazel mentally flipped through the pages of the books she’d memorized about the proper placement of arm bones and the ligaments connecting the muscle. Hazel lifted the scalpel. Are you ready? she repeated.

The knife entered just below the elbow. Instantly, the wound began to weep thin yellow liquid. The infection that had been making Martin’s arm tight and hot. Martin winced.

The pus kept coming—pints of it, it seemed, without any additional prodding from Hazel. I’m going to need a cloth. Is there a rag I can use?

Almost as soon as Hazel asked, there was the sound of stomping down the stairs. Two young girls with dark brown curls matted to their heads raced toward Hazel, both carrying squares of dishwater-gray cloth. The girls looked to be twins, no older than eight.

I brought, one of the girls said, holding up the fabric for Hazel.

The girl’s sister elbowed her sharply in the ribs. "No, I brought!"

Hazel graciously took both cloths and immediately put them to use soaking up the liquid still leaking from her incision. Thank you, girls. She said, Is this your brother? The twins nodded but they remained with their tiny mouths agape, unable to tear their eyes from their brother’s broken arm. Martin noticed, and pulled the leather piece from his mouth with his good hand.

Sue, May—get out of here. I told you that you was meant to stay upstairs, remember?

The girls acted like they couldn’t hear him. One of the girls—Sue, maybe—extended her index finger, readying herself to poke her brother’s injury.

Hazel swatted her hand out of the way before it made contact. Your brother is right. You’re going to need to go back upstairs if you want Martin to get well.

The girls giggled in place, undaunted by the yellow pus that had slightly abated but also thickened into greenish clumps. Hazel decided to try a new strategy. Girls, she said, fishing in her pocket and pulling out a few coins. Would you be able to get me one orange for your brother? It’s very important for Martin to have an orange if he’s going to get well. Can you do that for me?

Spellbound as the girls had been by the surgery, the coins in Hazel’s hand dazzled them more. They snatched the money so quickly it was as if they’d expected her palm to close, and then, without giving her enough time to change her mind, raced out the door to their task.

The room returned to relative silence. Hazel finished pressing the infection from the cut and washed the wound with water and the small bottle of alcohol she’d stolen from her father’s collection. All right, Hazel said, next we sew up the wound.

There were several drawbacks to being a young woman working as a surgeon, but there was also one advantage: years of her childhood had been spent on embroidery—on mastering the neat, orderly stitches that would, her mother had assured her, make fine gifts for her future mother-in-law one day—and that meant she was a prodigy when it came to stitching wounds.

Her older brother had been tutored in Latin and history and mathematics; when it came to science, Hazel was forced to listen at doors, learning through borrowed workbooks and lessons that George passed along. Hazel’s own lessons were in violin and piano. She was taught French and Italian. And she was forced to sit, for hours and hours, as the solarium filled with the still and stifling heat of late afternoon, sewing.

When she had dressed in her brother’s clothing and sneaked into the lectures at the Anatomists’ Society under an assumed name, pretending to be a boy, she was at the top of the class in every subject. But it was her stitches that forced even the famously strict and impassive Dr. Straine to acknowledge her skill.

Well, yes! one of the boys in class had scoffed after Straine admitted that Hazel’s work on the dead rabbit she had been assigned was impeccable. "He’s got these tiny hands, like a girl! I’d rather be worse at stitching and have bigger hands, if you know what I mean." The rest of the class had laughed until Straine shot them all a deadly look. Hazel stifled her own giggle.

Martin’s arm was stitched up in seconds, the line tidy and even. Hazel smiled at her work. It probably wouldn’t even leave a scar. Martin spat out his leather. Are we done, then? he asked. You did it, yeah? I’m better now?

Not quite.

Martin looked down at his arm. But I’m all sewed up!

Your arm was broken quite severely, Hazel said, pressing gingerly up from his elbow. In several places, from the feel of it. If we don’t reset it now, you might never be able to use your arm again. Or it might have to come off altogether.

Martin clenched his eyes shut. Just do it, then.

Hazel braced herself against the table, gripped his arm tight. She would have to position herself at the correct angle if she was going to be able to re-break the bone. Hazel took a deep breath, and exhaled hard while she pulled, summoning all the strength she could muster for one well-placed burst of force.

The crunch echoed through the small room.

Before Martin could scream, Hazel reset the arm firmly in place, where it could heal correctly. Both their foreheads glistened with sweat. Martin’s hair hung wet down at his ears, and a stain was blooming at both his armpits.

That’s it, then, Hazel said. She wiped the scalpel off on her apron and deposited it back into her bag before she turned to the work of wrapping Martin’s arm. But you’re not to move this arm for a week at the earliest. Change the dressing on the bandage over the stitches if it looks yellow, but not before, and tell your mum that you’re absolutely not to go to the shipyard for another month. There’s no work you’ll be able to do anyway.

Martin moved his arm slowly at the shoulder to test the tightness of the ties. Ain’t got no mum, he said, still looking at his arm.

What do you mean? All of your sisters, the girls?

Mum died with the twins. Is’a miracle they came out okay as they were. Tried to get a midwife when she was having them, but Mum said she had been through it all half a dozen times already and knew what she was doing. Besides, he added, not like we could afford a fancy doctor. He looked at Hazel with something halfway between gratitude and suspicion. So, I take care of us. All of ’em. I can go a week without work, but no longer.

At that moment, Martin’s two younger sisters reappeared at the door. One of them held a small, perfectly round orange in her palm, purchased for a penny from one of the carts lining High Street. We got it, said one girl. We got the orange. Very important.

Very important, her sister echoed.

Yes, Hazel said. Will you do your brother and me a big favor and peel it for us?

The girls eagerly accepted their task, using their tiny fingernails to dig into the flesh of the orange and peel its skin away. When the fruit inside was exposed—slightly lopsided and dripping juice from its messy excavation—one of the girls held it aloft in her hand and offered it to Hazel like a jewel.

Now, here’s the hardest part, Hazel said. You’re going to need to divide it into thirds, and help your brother eat his third without letting him use his hands. Do you know what thirds are? Enough for the three of you.

In answer, the girls began their work. Martin gratefully opened his mouth to allow one of his younger sisters to feed him a segment.

Can’t remember the last time we had an orange, Martin said, letting some of the juice run from the corner of his mouth and down his chin.

Well, good food will help you heal, Hazel said. That’s what this is for. She pointed to the small pile of coins she’d left on the table. So you can rest for a week at least.

Martin’s face contorted and he moved as if to push the coins away, but he only lifted his right arm an inch before he winced in pain and lowered it to his side once more. I don’t accept charity, he said, his voice suddenly colder and more frightful than it had been moments before, when Hazel was holding a blade to his skin.

It’s not charity, Hazel said. It’s treatment. What’s the point of me coming here and fixing your arm if you’re just going to ruin it tomorrow with a day of work at the docks?

Martin clenched his teeth. His sisters were in a corner of the room, sticky with orange juice, sharing segments of the fruit and sucking on the peel. I’m not going to thank you for that, he said finally, tilting his head toward the money. But thank you for fixing the arm.

You’re welcome, Hazel replied simply. She finished packing her black leather medical bag and gave a small bow to Martin, and then to his sisters. Ladies, she said. And Hazel Sinnett exited their flat and reemerged onto the streets of Crichton’s Close, walking briskly toward her next appointment with the still-rising sun at her back. There was another bonesetting to do, and two tooth extractions, and a case of syphilis to treat. And Mrs. Bede’s baby would be due any day now. There was work to be done.

Notes from Hazel Sinnett, A Treatise on Modern Medicine (Unpublished)

Though the speed at which the Roman fever seizes its patients varies, the presentation of symptoms is—perhaps comfortingly—routine. First, patients report a few days of weariness, but an inability to sleep, and feverishness. Soon, the pustules (buboes) appear on the body, typically the back, upper arms, and legs.

The buboes fill with blood and become red-purple, and eventually burst. Contrary to popular opinion, Roman fever is not so named because it originated in Italy (earliest cases were identified in London and Bavaria) but because when the buboes burst, the shirts of patients become stained with a blood pattern that resembles multiple stab wounds, akin to Julius Caesar being stabbed on the steps of the Roman Senate.

Though neither cure nor prevention has been identified, wortroot has been proved in my practice to ameliorate the symptoms and stave off death. I have applied wortflower root in a salve and administered it as tea, and will report on the more efficacious course of action. Will also remain abreast as to literature on whether the Roman fever can be prevented via inoculation. (Do not yet feel confident enough to test it on patients nor self.)

Wortflower tea: dry and powder several stems of the wortflower plant, steep in hot water with honey and lemon. For salve: powder the dried herb and add oil and warm candle wax.

Additional treatment for the Roman fever: cardamom seeds and warm milk in the evening, for strength.

2

Hazel Sinnett Dreamed of Fingers. Bony, spindly fingers, with knuckles knobbed like walnuts and gray-green flesh peeling off in thin strips. Sometimes the fingers weren’t attached to any hands at all: sometimes they were like living things, set on a flat table, twitching like insect legs. Sometimes in her dreams, she saw Dr. Beecham’s fingers, the way they had looked when the famed surgeon pulled off his leather gloves for her at the Anatomists’ Society to reveal the truth of what he hid beneath: swollen digits, some purple and black, sewn onto his hand.

Fingers that had fallen off and been reattached. A pinkie finger that looked like it never belonged to him in the first place.

No. She never woke up from her dreams panting or crying out, with sweat dampening the hair to her forehead. She never felt her heart racing. She never talked or shouted in her sleep. Her lady’s maid, Iona, never had need to rush in with a cool cloth and soothing cup of tea. Hazel’s nightmares didn’t scare her any longer.

One night, she had dreamed of a single index finger, with bone visible at the knuckles, still dripping blood, pulling itself toward her like an inchworm. When she woke up, Hazel was thinking of the stitches she would have selected to reattach it to a hand.

She no longer had time for fear or horror at blood or decay: working as a surgeon meant every second mattered more than the last. A mere instant, the time it would take to recoil or stifle a gasp, might mean the difference between life and death. She had work to do. And in the past few months, she had been very, very busy.

Easy there!

Hazel pulled her plate of toast from the table, rescuing it from where Iona’s belly had almost knocked it to the floor. The young woman was five months along now—Hazel forced her to submit to regular examinations and consultations—but Iona still didn’t seem aware of the damage she could cause when walking through close quarters.

Hmm? Iona said, spinning around, knocking an empty plate to the floor. Mercifully, it spun and settled, unbroken.

No, no, I’ll get it! Hazel said, seeing Iona begin to reach down to pick it up.

It’s this blasted belly, Iona said, rubbing it absentmindedly. Already the size of a shoulder of mutton. And to think I’m going to get even bigger. How many months you say I have to go now?

Four, Hazel said. And I’m not going to want you working at Hawthornden much longer, do you hear me? Bed rest soon, especially if the little darling continues to grow at the rate he’s been doing so far. I’m delivering this child, so you’ll do as I say now.

Charles says all the babes in his family are hearty types. Come out with full sets of hair and full sets of teeth, Iona said, depositing herself at the table in the chair next to Hazel and letting out an oof.

Lord have mercy, Hazel murmured.

And, Iona said, I’ll work at the house as long as I well like, miss. She hadn’t even had the child yet, and she was already addressing Hazel like she was a mother, never mind the fact that they were all but the same age. Who else is going to keep you fed when you’re working late in the night?

Hazel grimaced. These hours are only until I finish my treatise. Then I’ll start keeping normal hours.

"Aye, your treatise." Iona rolled her eyes and bit into a piece of toast. Hazel had talked of little else for the past few months: her lofty goal of developing a new, updated guidebook on anatomy and basic household treatments, complete with her own illustrations.

The idea was a book of anatomy written in the style of a household manual, the type of book anyone with the ability to read would be able to understand, with diagrams of the human body and its components and advice on home treatments. Dr. Beecham’s Treatise on Anatomy; or, The Prevention and Cure of Modern Diseases was a masterwork in the field, of course; it was the achievement of a lifetime (or several lifetimes, Hazel reminded herself), but it was also a tome thick enough to kill a man if it fell upon him from a high shelf, and nearly impenetrable for anyone without a specific interest in physiology. Hazel’s book would be different—influenced by the manuals for proper etiquette and entertaining that seemed to just appear as if by magic in a young woman’s sitting room as soon as she turned fifteen.

Common people have bodies, Hazel reasoned; there’s no reason they can’t understand how those bodies work. And so many of them cannot afford doctors, or the ones they can afford are charlatans or else poorly trained. Hazel understood with genuine clarity that a straightforward guide to effective home remedies could save lives.

The problem, of course, was that as noble as her intentions were, Hazel had inadvertently begun a staggering undertaking. A book meant to identify common ailments and their treatment could take years if she was thorough, and on top of that, Hazel wanted detailed diagrams and descriptions of the major systems and organs of the body. The drawings of the organs in Beecham’s book were neat as sewing patterns: Hazel had been shocked when the first corpse was opened in front of her and she saw what truly existed beneath our skin, the wet and dark and bleeding mass of flesh. It was frightening to know that that was all we were, that the human soul existed somewhere in that putrid, writhing soup. But it needn’t be frightening. It could be explained, and she could be the one to explain it, with drawings and diagrams and language that read the way people talked.

Since Jack’s trial and hanging, it had become nearly impossible for medical students to get fresh bodies. Hazel was forced to work from old notes, diagrams she had drawn back when she was studying for the Royal Examination. Of course, in the end, she hadn’t taken the test at all. She had followed Dr. Beecham to his surgical hall, watched him attempt to transplace an eye from a living patient into another man, and then try to take the beating heart from Jack Currer’s body. She had stopped the doctor, but it wasn’t enough. She hadn’t done enough to save Jack’s life. Jack was