What was in the bag Cecil Barker fished out of the moat?

The bag that Cecil Barker fished out of the moat contained boots, clothing, and a knife. It was weighed down with a dumbell.

From within he extracted a dumb-bell, which he tossed down to its fellow in the corner. Next he drew forth a pair of boots. “American, as you perceive,” he remarked, pointing to the toes. Then he laid upon the table a long, deadly, sheathed knife. Finally he unravelled a bundle of clothing, comprising a complete set of underclothes, socks, a gray tweed suit, and a short yellow overcoat.