What had happened? Had he fallen into the lake while under the influence of drink? Had he committed suicide? Or had he—

Somehow this last reflection startled me. Was it possible there had been foul play?

I had to leave the body there, for I found it impossible to lift it on to the bank without help.

“The great house,” as the tenantry called it, was still locked when I got back there. Silence still reigned everywhere. The driver of my taxi was fast asleep on his seat.

When I prodded him with my stick he sat up with a start, and apologised.

“Get back to Oakham as quickly as you can,” I said to him as I stepped into the car and slammed the door.

He turned his starting handle without result. He lifted the bonnet, and for a long time examined the machinery. Then, removing his coat, he wormed himself underneath the car, lying flat upon his back.

When at last he emerged he was red in the face and perspiring freely.

“Oh, by the way, sir,” he said suddenly, picking up his coat and thrusting his hand into one of its pockets, “I think you dropped this.”

As he stopped speaking he pulled his hand out and held out to me a little silver flask about four inches square.