“Try Canadian Pacific Railway,” said Holmes.

Stanley Hopkins swore between his teeth, and struck his thigh with his clenched hand.

“What a fool I have been!” he cried. “Of course, it is as you say. Then ‘ J. H. N. ’ are the only initials we have to solve. I have already examined the old Stock Exchange lists, and I can find no one in 1883 , either in the house or among the outside brokers, whose initials correspond with these. Yet I feel that the clue is the most important one that I hold. You will admit, Mr. Holmes, that there is a possibility that these initials are those of the second person who was present⁠—in other words, of the murderer. I would also urge that the introduction into the case of a document relating to large masses of valuable securities gives us for the first time some indication of a motive for the crime.”