Some anonymous child had spilled one bowl; Adso had knocked another onto the floor, maddened by the scent of goose broth, and had lapped up the contents, mold and all, with every evidence of enjoyment. There obviously hadn’t been anything toxic in that one; I glanced down at the little cat, curled up in a pool of sunshine on the floor, the picture of somnolent well-being.

In three of the remaining bowls, though, spongy velvet mats of mottled blue covered the surface, and my examination of a sample taken from one of them had just confirmed that I did indeed have what I sought. It wasn’t the mold itself that was antibiotic—it was a clear substance secreted by the mold, as a means of protecting itself from attack by bacteria. That substance was penicillin, and that was what I wanted.

I had explained as much to Jamie, who sat on a stool watching me as I poured the broth from each live culture through another bit of gauze to strain it.

“So what ye’ve got there is broth that the mold has pissed in, is that right?”

“Well, if you insist on putting it that way, yes.” I gave him an austere glance, then took up the strained solution and began distributing it into several small stoneware jars.

He nodded, pleased to have got it right.

“And the mold piss is what cures sickness, aye? That’s sensible.”

“It is?”

“Well, ye use other sorts of piss for medicine, so why not that?”

He lifted the big black casebook in illustration. I had left it open on the counter after recording the latest batch of experiments, and he had been amusing himself by reading some of the earlier pages, those recorded by the book’s previous owner, Dr. Daniel Rawlings.

“Possibly Daniel Rawlings did—I don’t.” Hands busy, I lifted my chin at the entry on the open page. “What was he using it for?”

“Electuary for the Treatment of Scurvy,” he read, finger following the neat small lines of Rawlings’s script. “Two Heads of Garlic, crushed with six Radishes, to which are added Peru Balsam and ten drops of Myrrh, this Compound mixed with the Water of a Man-child so as to be conveniently drunk.”

“Bar the last, it sounds like a rather exotic condiment,” I said, amused. “What would it go with best, do you think? Jugged hare? Ragout of veal?”

“Nay, veal’s too mild-flavored for radish. Hodgepodge of mutton, maybe,” he replied. “Mutton will stand anything.” His tongue flicked absentmindedly across his upper lip in contemplation.

“Why a man-child, d’ye think, Sassenach? I’ve seen the mention of it in such receipts before—Aristotle has it so, and so have some of the other ancient philosophers.”

I gave him a look, as I began tidying up my slides.

“Well, it’s certainly easier to collect urine from a male child than from a little girl; just try it, sometime. Oddly enough, though, urine from baby boys is very clean, if not entirely sterile; it may be that the ancient philosophers noticed they had better results with it in their formulae, because it was cleaner than the usual drinking water, if they were getting that from public aqueducts and wells and the like.”

“Sterile meaning that it hasna got the germs in it, not that it doesna breed?” He gave my microscope a rather wary glance.

“Yes. Or rather—it doesn’t breed germs, because there aren’t any there.”

With the countertop cleared, save for the microscope and the jars of penicillin-containing broth—or at least I hoped that’s what they were—I began the preparations for surgery, taking down my small case of surgical instruments, and fetching a large bottle of grain alcohol out of the cupboard.

I handed this to Jamie, along with the small alcohol burner I had contrived—an empty ink bottle, with a twisted wick of waxed flax drawn up through a cork stuck into the neck.

“Fill that up for me, will you? Where are the boys?”

“In the kitchen, getting drunk.” He frowned in concentration, carefully pouring the alcohol. “Is the urine of wee lassies not clean, then? Or is it only harder to get?”

“No, actually, it isn’t as clean as that of boys.” I unfolded a clean cloth on the countertop and laid out two scalpels, a pair of long-nosed forceps, and a bunch of small cautery irons. I dug about in the cupboard, unearthing a handful of cotton pledgets. Cotton cloth was hideously expensive, but I had had the good fortune to cajole a sack of raw cotton bolls from Farquard Campbell’s wife, in return for a jar of honey.

“The . . . um . . . route to the outside isn’t quite so direct, you might say. So the urine tends to pick up bacteria and bits of debris from the skin folds.” I looked over my shoulder at him and smiled. “Not that you ought to go feeling superior on that account.”

“I shouldna dream of it,” he assured me. “Are ye ready, then, Sassenach?”

“Yes, fetch them in. Oh, and bring the basin!”

He went out, and I turned to face the east window. It had snowed heavily the day before, but today was a fine, bright day, clear and cold, with the sun reflecting off the snow-covered trees with the light of a million diamonds. I couldn’t have asked for better; I should need all the light I could get.

I set the cautery irons in the small brazier to heat. Then I fetched my amulet from the cabinet, put it round my neck so it hung beneath the bodice of my gown, and took down the heavy canvas apron from its hook behind the door. I put that on, too, then went to the window and looked out at the cold icing-sugar landscape, emptying my mind, steadying my spirit for what I was about to do. It was not a difficult operation, and I had done it many times before. I had not, however, done it on someone who was sitting upright and conscious, and that always made a difference.

I hadn’t done it in several years, either, and I closed my eyes in recollection, visualizing the steps to take, feeling the muscles of my hand twitch slightly in echo of my thoughts, anticipating the movements I would make.

“God help me,” I whispered, and crossed myself.

Stumbling footsteps, nervous giggles, and the rumble of Jamie’s voice came from the hallway, and I turned round smiling to greet my patients.

A month of good food, clean clothes, and warm beds had improved the Beardsleys immensely, in terms of both health and appearance. They were both still small, skinny, and slightly bowlegged, but the hollows of their faces had filled out a bit, their dark hair lay soft against their skulls, and the look of hunted wariness had faded a little from their eyes.

In fact, both pairs of dark eyes were presently a little glazed, and Lizzie was obliged to grab Keziah by the arm in order to prevent his stumbling over a stool. Jamie had Josiah gripped firmly by the shoulder; he steered the boy over to me, then set down the pudding basin he carried under his other arm.

“All right, are you?” I smiled at Josiah, looking deep into his eyes, and squeezed his arm in reassurance. He swallowed hard, and gave me a rather ghastly grin; he wasn’t drunk enough not to be scared.

I sat him down, chatting soothingly, wrapped a towel round his neck, and set the basin on his knees. I hoped he wouldn’t drop it; it was china, and the only large pudding basin we had. To my surprise, Lizzie came to stand behind him, putting her small hands on his shoulders.

“Are you sure you want to stay, Lizzie?” I asked dubiously. “We can manage all right, I think.” Jamie was thoroughly accustomed to blood and general carnage; I didn’t think Lizzie could ever have seen anything beyond the common sorts of illness and perhaps a childbirth or two.

“Oh, no, ma’am; I’ll stay.” She swallowed, too, but set her small jaw bravely. “I promised Jo and Kezzie as I’d stay with them, all through.”

I glanced at Jamie, who lifted one shoulder in the hint of a shrug.

“All right, then.” I took one of the stoneware jars of penicillin broth, poured it into two cups, and gave one to each of the twins to drink.

Stomach acid would likely inactivate most of the penicillin, but it would—I hoped—kill the bacteria in their throats. Following surgery, another dose washed over the raw surfaces might prevent infection.

There was no way of knowing exactly how much penicillin there might be in the broth; I might be giving them massive doses—or too little to matter. At least I was reasonably sure that whatever penicillin was in the broth was presently active. I had no means of stabilizing the antibiotic, and no notion how long it might be potent—but fresh as it was, the solution was bound to be medicinally active, and there was a good chance that the rest of the broth would remain usable for at least the next few days.

I would make new cultures, as soon as the surgery was complete; with luck, I could dose the twins regularly for three or four days, and—with greater luck—thus prevent any infections.

“Oh, so ye can drink the stuff, can ye?” Jamie was eyeing me cynically over Josiah’s head. I had injected him with penicillin following a gunshot injury a few years before, and he obviously now considered that I done so with purely sadistic intent.

I eyed him back.

“You can. Injectable penicillin is much more effective, particularly in the case of an active infection. However, I haven’t any means of injecting it just at present, and this is meant to prevent them getting an infection, not to cure one. Now, if we’re quite ready . . .”

I had thought that Jamie would restrain the patient, but both Lizzie and Josiah insisted that this was not necessary; Josiah would sit quite still, no matter what. Lizzie still gripped his shoulders, her face paler than his, and her small knuckles sharp and white.

I had examined both boys at length the day before, but had another quick look before starting, using a tongue depressor made of a slip of ash wood. I showed Jamie how to use this to keep the tongue pressed out of my way, then took up forceps and scalpel and drew a long breath.

I looked deep into Josiah’s dark eyes, and smiled; I could see two tiny reflections of my face there, both looking pleasantly competent.

“All right, then?” I asked.

He couldn’t speak, with the tongue depressor in his mouth, but made a good-natured sort of grunt that I took for assent.

I needed to be quick, and I was. The preparations had taken hours; the operation, no more than a few seconds. I seized one spongy red tonsil with the forceps, stretched it toward me, and made several small, quick cuts, deftly separating the layers of tissue. A trickle of blood was running out of the boy’s mouth and down his chin, but nothing serious.

I pulled the gobbet of flesh free, dropped it into the basin, and shifted my grip to the other tonsil, where I repeated the process, only a trifle more slowly in consequence of working backhanded.

The whole thing couldn’t have taken more than thirty seconds per side. I drew the instruments out of Josiah’s mouth, and he goggled at me, astonished. Then he coughed, gagged, leaned forward, and another small chunk of flesh bounced into the basin with a small splat, together with a quantity of bright red blood.

I seized him by the nose and thrust his head back, stuffed pledgets into his mouth to absorb sufficient blood that I could see what I was doing, then snatched a small cautery iron and took care of the largest vessels; the smaller ones could clot and seal on their own.