“That is where he put his foot in getting out. If you can trace him, I should think that Toby will have no difficulty. Now run downstairs, loose the dog, and look out for Blondin.”

By the time that I got out into the grounds Sherlock Holmes was on the roof, and I could see him like an enormous glowworm crawling very slowly along the ridge. I lost sight of him behind a stack of chimneys, but he presently reappeared, and then vanished once more upon the opposite side. When I made my way round there I found him seated at one of the corner eaves.

“That you, Watson?” he cried.

“Yes.”

“This is the place. What is that black thing down there?”

“A water-barrel.”

“Top on it?”