"I should have thought you could see that with the naked eye," said the inspector, with a sly grin at me. "It's a pretty bold design."
"Yes," replied Thorndyke; "a very interesting production. What do you say, Mr. Marchmont?"
The solicitor took the note, and I looked over his shoulder. It was certainly a curious production. Written in red ink, on the commonest notepaper, and in the same sprawling hand as the address, was the following message: "You are given six days to do what is just. By the sign above, know what to expect if you fail." The sign referred to was a skull and crossbones, very neatly, but rather unskilfully, drawn at the top of the paper.
"This," said Mr. Marchmont, handing the document to Mr. Curtis, "explains the singular letter that he wrote yesterday. You have it with you, I think?"
"Yes," replied Mr. Curtis; "here it is."
He produced a letter from his pocket, and read aloud:
"'Yes: come if you like, though it is an ungodly hour. Your threatening letters have caused me great amusement. They are worthy of Sadler's Wells in its prime.
"'ALFRED HARTRIDGE.'"
"Was Mr. Hartridge ever in Italy?" asked Inspector Badger.
"Oh yes," replied Mr. Curtis. "He stayed at Capri nearly the whole of last year."
"Why, then, that gives us our clue. Look here. Here are these two other letters; E.C. postmark—Saffron Hill is E.C. And just look at that!"