“Though not disputed even by yourself.”

“No. That is true.”

“Do you dispute my theory, though?”

“No.”

“And is there any way of finding out whether I am correct except by testing it against result? That is surely the basis of experimental philosophy?”

“That is Monsieur Descartes’s basis,” he said, “if I understand him correctly. To frame a hypothesis, then amass evidence to see if it is correct. The alternative, proposed by my Lord Bacon, is to amass evidence, and then to frame an explanation which takes into account all that is known.”

In retrospect, looking back over the conversation which I noted diligently in the book which was with me on my travels and which I now reread for the first time in many years, I see many things which were obscured from my understanding then. The English detestation of foreigners leads very swiftly to a wish to ignore any advance which stems from what they consider faulty methods, and allows this proudest of people to claim all discoveries as their own. A discovery based on faulty premises is no discovery—all foreigners influenced by Descartes employ faulty premises, and therefore… Hypotheses non fingo. No hypotheses here—is that not the trumpet blast of Mr. Newton as he assails Leibniz as a thief for having the same ideas as himself? But at that time I merely thought my friend was using argument as a means of furthering our knowledge.

“I believe your summary of Monsieur Descartes does him scant justice,” I said. “But no matter. Tell me how you would you proceed.”

“I would begin by transfusing blood between animals—young and old of the same type, then between different types. I would transfuse water into an animal’s veins, to see whether the same response was elicited. Then, I would compare all the results to see what exactly the effects of transfusing blood are. Finally, when I could proceed with certainty, I would make the attempt on Mrs. Blundy.”

“Who by then would have been dead for a year or more.”

Lower grinned. “Your unerring eye has spotted the weakness of the method.”

“Are you suggesting I should not do this?”

“No. It would be fascinating. I merely doubt whether it is well founded. And I am certain that it would cause scandal. Which makes it a dangerous business to discuss publicly.”

“Let me put it another way. Will you help me?”

“Naturally I should be delighted. I was merely discussing the issues that are raised. How would you proceed?”

“I don’t know,” I said. “I thought that maybe a bull might serve. As strong as an ox, you know. But good reasons rule that out. The blood has a tendency to congeal. So it would be imperative to transport it immediately from one creature into the other without delay. And we could hardly bring an ox in. Besides, the blood transports the animal spirit, and I would be loath to infuse the bestiality of an ox into a person. That would be an offense against God, who has set us higher than the animals.”

“Your own, then?”

“No, because I would need to attend to the experiment.”

“There is no problem. We can easily find someone. The best person,” he continued, “would be the daughter. She would be willing, for her mother’s sake. And I’m sure we could impress on her the need for silence.”

I had forgotten about the daughter. Lower saw my face fall, and asked me what was the matter. “She was so insufferably offensive last time I visited the house I vowed never to set foot there again.”

“Pride, sir, pride.”

“Perhaps. But you must understand that I cannot give way. She would have to come to me on her knees before I would reconsider.”

“Leave that for a moment. Assuming you could do this experiment—just assuming—how much blood would you need?”

I shook my head. “Fifteen ounces, maybe? Perhaps twenty. A person can lose that much without too many ill effects. Maybe more at a later stage. What I don’t know is how to effect the transportation. It struck me that the blood would have to leave the one body and enter the other in the same place—vein to vein, artery to artery. I would recommend slitting the jugular, except that it’s fearfully difficult to stop it up again. I don’t want to save the mother and have the daughter bleed to death. So maybe one of the major vessels in the arm. A band to make it swell up. That’s the easy part. It is the transference which concerns me.”

Lower got up and wandered around the room, rummaging around in his pockets.

“Have you heard of injections?” he asked eventually.

I shook my head.

“Ah,” he said. “A splendid idea, which we have been working on.”

“We?”

“Myself, Dr. Willis and my friend Wren. Similar in some ways to your idea. What we do, you see, is take a sharp instrument and push it into a vein, then squeeze liquids straight into the blood, avoiding the stomach entirely.”

I frowned. “Extraordinary. What happens?”

He paused. “We have had mixed results,” he confessed. “The first time it worked marvelously. We injected an eighth-cup of red wine straight into a dog. Not enough to make it even tipsy, usually, but by this method it turned rolling drunk.’’ He grinned at the thought. “We had a terrible time controlling it. It jumped off the table and ran around, then fell over after bumping into a cupboard of plates. We could barely control ourselves. Even Boyle cracked a smile. The important thing is that it seems a little liquor injected has much more of an effect than when taken through the stomach. So we took a mangy old beast next time and injected sal ammoniack.”

“And?”

“It died, and in some considerable pain. When we opened it up, the corrosion to its heart was considerable. We tried injecting milk the next time to see if we could bypass the need to eat. But it curdled in the veins, unfortunately.”

“Died again?”

He nodded. “We must have overdone the amount. We’ll cut it back next time.”

“I would be fascinated if you would allow me to attend.”

“A pleasure. My point is that we could use the same idea for transferring your blood. You don’t want the blood exposed to the air, because it might congeal. So you take a pigeon quill, which can be made very thin and sharp. Put a hole in the end and insert it into Sarah’s vein. Join it to a long silver tube, which has a narrow diameter, with another quill in the mother’s vein. Wait for the blood to flow, then stop the flow in the mother’s vein above the slit. Join the two together, and count. I’m afraid we’d have to guess about how much comes out. If we let the blood flow into a bowl for a few seconds, we’ll have some idea of how fast it is going.”

I nodded enthusiastically. “Wonderful,” I said. “I’d been thinking about cupping. This is much neater.”

He grinned, and held out his hand. “By God, Mr. Cola, I’m glad you’re here. You’re a man after my own heart, truly you are. In the meantime, which of us is going to see Grove for poor Prestcott?”