"Next, I wanted to be thoroughly vetted—as a man of thirty-three, you understand. It's all very well looking young, but you want to know whether you're really as young inside as you look. So I told him some sort of a yarn about an insurance policy and wanting to be overhauled for my own satisfaction before going to the company's doctor. So he asked me my age—thirty-three, I said—and ran all over me; and he was good enough to say that I was a very fine man and needn't worry about not being passed as a first-class life."

"And then?"

"Then I told him another cock-and-bull story. It was as an author that he'd met me before, you see, so I told him I was writing some fantastic sort of a book, and wanted one or two medical facts right. I had to go rather carefully here, of course, but I gave him, as nearly as I dared, an outline of what had happened, and asked him what about it."

"And what did he say?"

"He saw nothing very extraordinary in it," said Derwent Rose.

I jumped half out of my chair. "What! What madman was this?"

Then I saw the faint flicker of his smile, and sat down again.

"Quite a distinguished madman, George; incidentally he's a Knight.... But I don't want to pull your leg, old fellow. He didn't put it quite that way. What he actually did say was that the more a man studied these things the less he would swear that anything was an impossibility. And he's a remarkable man, mind you. I've not much use for the average doctor, but this fellow's big enough to use plain English and when he doesn't know a thing to say so. His knowledge isn't just how to conceal his ignorance. And he might have been a novelist himself from the way he instantly grasped what I wanted to know."

Not an impossibility!... I couldn't have spoken. I waited enthralled. Derry continued.

"So he began to talk about the ductless glands. Not just the thyroid. Everybody's got thyroid on the brain nowadays, but the thyroid's only one of them. There are a dozen others. And then he told me that practically nothing was known about them."