Then he looked at me. "The reason why I am speaking to you is this,"
I said. "I want to find out what a decent citizen like yourself will
think of something I know. It concerns the Blue Disease and its origin."

He seemed disturbed, and took out his watch.

"I ought to get home. My wife----"

"Is your wife ill?"

"Yes."

"What's the matter with her?"

He frowned.

"Dr. Sykes thinks it's lung trouble."

"Consumption?"

He nodded, and an expression of anxiety came over his face.

"Good," I exclaimed. "Now listen to what I have to say. Before the week
is out your wife will be cured. I swear it."

He said nothing. It was plain that he was still suspicious.

"You read what they say in the papers about the Blue Disease cutting
short other diseases? Well, that Blue Disease will be all over London in
a day or two. Now do you understand?"

I saw that I had interested him. He settled himself on his chair, and
began to examine me. His gaze travelled over my face and clothes,
pausing at my cuff-links and my tie and collar. Then he looked at my
card again. Inwardly he came to a decision.

"I'm willing to listen to what you've got to say," he remarked, "if you
think it's worth saying."

"Thank you. I think it's worth hearing." I leaned my arms on the table
in front of me. "This Blue Disease is not an accidental thing. It was
deliberately planned, by two scientists. I was one of those scientists."

"You can't plan a disease," he remarked, after a considerable silence.

"You're wrong. We found a way of creating new germs. We worked at the
idea of creating a particular kind of germ that would kill all other
germs ... and we were successful. Then we let loose the germ on the
world."

"How?"

"We infected the water supply of Birmingham at its origin in Wales."

I watched his expression intently.

"You mean that you did this secretly, without knowing what the result
would be?" he asked at last.

"We foresaw the result to a certain extent."

He thought for some time.

"But you had no right to infect a water supply. That's criminal,
surely?"

"It's criminal if the infection is dangerous to people. If you put
cholera in a reservoir, of course it's criminal."

"But this germ...?"

"This germ does not kill people. It kills the germs in people."

"What's the difference?"

"All the difference in the world! It's like this.... By the way, what is
your name?"

"Clutterbuck." The word escaped his lips by accid