22.
The cunning rogues guessed that the usual plan would be acted upon, and the suspected thief allowed to visit the scene where his hoard lay hidden.
"It had all been foreseen, and Robertson must have been constantly on the watch.

The tramp stopped, mind you, in Phillimore Terrace for some moments, lighting a pipe.

The accomplice, then, was fully on the alert; he slipped the bolts of the back garden gate.

Five minutes later Knopf was in the house, in a hot bath, getting rid of the disguise of our friend the tramp.

Remember that again here the detective did not actually see him.
"The next morning Mr.Knopf, black hair and beard and all, was himself again.