interrupt him, but follow him as discreetly as you can. Dr. Watson and I will not be far off. By the way, where is the key of that little box of which you spoke?"
"Upon his watch-chain."
"I fancy our researches must lie in that direction. At the worst the lock should not be very formidable. Have you any other able-bodied man on the premises?"
"There is the coachman, Macphail."
"Where does he sleep?"
"Over the stables."
"We might possibly want him. Well, we can do no more until we see how things develop. Good-bye—but I expect that we shall see you before morning."
It was nearly midnight before we took our station among some bushes immediately opposite the hall door of the Professor. It was a fine night, but chilly, and we were glad of our warm overcoats. There was a breeze and clouds were scudding across the
