"I see, and 'L' being the second letter of the sixth angle you put a dot."
"Of course. If I wrote 'K' I should put no dot," replied Harry, and took a morsel of paper out of his pocket. "Here," said he, "is a copy of the sign on the dead man's arm. The second letter of ninth angle criss-cross: the first letter second angle St. Andrew's cross, and the second letter fourth angle of the same. Do you see? Now take this pencil, Bob, and use the key to turn them into letters."
Ellis did so, and produced three letters on the paper given to him. "'R U Z,'" he read slowly. "What does that mean? Is it a word?"
"I don't think so. There is no word spelt 'Ruz' in any language that I am acquainted with. I believe those three letters are the initials of the man who killed Moxton. For some reason the dying man did not desire to give up his murderer to justice, but at the same time he wished to let his wife know who struck the blow, hence the cypher. Mrs. Moxton can read the meaning, depend upon it, Bob."
"It seems strange," assented Ellis, surveying the letters thoughtfully. "Do you think there are three names here, or only two?"
"I can't say. 'R U' may mean Rupert or Rudolph, but I am in the dark so far. I have discovered the letters, Bob; it is for Mrs. Moxton to explain them to you."
"What about this other sign?" said the doctor, evading a reply.
"Well, at first I thought it was a serpent, but as it has four feet and a wriggle of a tail, I conclude it is a lizard. Mere guessing, you understand."
"What connection can it have with the letters?"
"I don't know. Ask me something easier, or rather," said Cass, with a peculiar smile, "ask Mrs. Moxton. She knows the truth about letters, and lizard and murder. But she won't tell it to you."