“Well, gentlemen, I can’t think of anywhere else. Of course, there’s the Ruff⁠—”

“What’s that?” I asked.

“The big chalk headland in Kent, close to Bradgate. It’s got a lot of villas on the top, and some of the houses have staircases down to a private beach. It’s a very high-toned sort of place, and the residents there like to keep by themselves.”

I tore open the Tide Tables and found Bradgate. High tide there was at 10:27 p.m. on the 15th of June .

“We’re on the scent at last,” I cried excitedly. “How can I find out what is the tide at the Ruff?”