“Why? Be reasonable, Bertie. If you were your aunt, and you knew the sort of chap you were, would you let a fellow you knew to be your best pal tutor your son?”

This made the old lemon swim a bit, but I got his meaning after awhile, and I had to admit that there was much rugged good sense in what he said. Still, he hadn’t explained what you might call the nub or gist of the mystery.

“I thought you were in America,” I said.

“Well, I’m not.”

“Why not?”

“Never mind why not. I’m not.”

“But why have you taken a tutoring job?”