“By some one who signs the letter ‘The Brown Robin.’”
“Let me see that letter,” demanded Nick.
“Well, I don’t know that I ought.”
“Now, Mr. Cary,” said Nick, sternly, “you were blackmailed last night; indeed, it was more nearly like robbery, for the money was taken from your hands while you were hesitating whether you would pay it over or not.”
“You know that? How?” asked Mr. Cary.
“Never mind how I know,” replied Nick, sternly. “It is my business to know a great many things. But I want to say this: I mean to investigate this matter to the bottom. If you help me by giving me all the information in your possession, so much the better, but whether you do or not I shall find all out. Now choose which you will do.”
“Well, I had intended to retain you, but this letter——”
“Let me see it,” demanded Nick, in a decided tone.
Mr. Cary yielded, and, taking the letter from his breast pocket, handed it to Nick.
At a glance the famous detective saw that it was the same handwriting, on the same kind of paper, as the two letters he had received in the morning. It read: