“There are no such signs, and no ticket has been found.”

“No record of a door being found open?”

“None.”

“We have had some fresh evidence this morning,” said Lestrade. “A passenger who passed Aldgate in an ordinary Metropolitan train about 11:40 on Monday night declares that he heard a heavy thud, as of a body striking the line, just before the train reached the station. There was dense fog, however, and nothing could be seen. He made no report of it at the time. Why, whatever is the matter with Mr. Holmes?”