“ ’16 Ivy Lane, Brixton,’ he answered. ‘But don’t let yourself be drawn away upon a false scent, Mr. Phelps. Come to the other end of the street and let us see if we can hear of anything.’

“Nothing was to be lost by following his advice. With the policeman we both hurried down, but only to find the street full of traffic, many people coming and going, but all only too eager to get to a place of safety upon so wet a night. There was no lounger who could tell us who had passed.

“Then we returned to the office, and searched the stairs and the passage without result. The corridor which led to the room was laid down with a kind of creamy linoleum which shows an impression very easily. We examined it very carefully, but found no outline of any footmark.”

“Had it been raining all evening?”

“Since about seven.”