He explained also how the other man could have got out of the park speedily without being observed.

The fog, though not very dense, was in his favour.

He seemed to have escorted the other to the spot, and then to have left him there to do the job single-handed.
Taking the time those two were seen coming out of Maze Hill Station by the old woman, and the time when the explosion was heard, the Chief Inspector thought that the other man might have been actually at the Greenwich Park Station, ready to catch the next train up, at the moment his comrade was destroying himself so thoroughly.
"Very thoroughly--eh ?" murmured the Assistant Commissioner from under the shadow of his hand.
The Chief Inspector in a few vigorous words described the aspect of the remains.

"The coroner's jury will have a treat," he added grimly.
The Assistant Commissioner uncovered his eyes.
"We shall have nothing to tell them," he remarked languidly.
He looked up, and for a time watched the markedly non-committal attitude of his Chief Inspector.

His nature was one that is not easily accessible to illusions.