"I'll be ready in five minutes," she said as she left the room.
"Now what the devil does this mean?" I said to myself.
Five minutes of course meant quarter of an hour, and then we sallied forth into the night, she in a long tweed coat and I in my inevitable oilskin.
"Which way do you want to go?" she asked.
"Suppose we work our way towards the north end," I suggested.
She said nothing more and we made our way by a track to the shore and then turned toward the left. I had been filling my pipe and when we got to the last stone wall, I stopped, bent under its shelter and struck a match. My face was towards her and in the fraction of a second before the first match blew out I caught a glimpse of something just visible in the mouth of one of the big pockets of her tweed coat. It was the butt end of a pistol.
I struck three more matches before I got my pipe alight and I contrived to face her each time, but she had turned and kept her other side towards me. When we resumed our walk I noticed that she consistently kept two or three yards away from me.
"Just shooting distance!" I said to myself.
"By the way, what are we supposed to be looking for?" I enquired presently.
"Chiefly periscopes, I think," said she.