“What have you found now?” he asked.
“There’s a murderer loose.”
“Murderer! I had no idea…”
“He’s only murdering baby trout,” John explained. “But he must be caught. This pool’s got two dozen trout in it, and the next one has two hundred. What do you make of it?”
“Anything I said would be a mere guess.”
“Well, I’m guessing too. But here goes. A mink or otter raiding these fingerlings would get up those riffles into the next pool and work on the fish there. A man who might be poaching ‘em would do the same thing. So something that lives among ’em, another fish, is getting these fingerlings. He’s too big to swim up the two inches of water into the next pool. But he can range from here to Big Kettle River.”
Professor Crandall smiled.
“A logical deduction, John. Can you identify the vil
