"Well, yes, I have an idea, but it's pretty vague. I overheard a little of a conversation not intended for my ears, and from that I got the notion, or perhaps it's only a suspicion, that the message contains the British naval or aeronautical wireless code."
"At any rate, it's of great importance," suggested Lieut. Osborne.
"Oh, there's no doubt about that," Tourtelle, or Hessenburg, assured.
"Are you an artist?" was the inquisitor's next question.
"Yes, I am; that is, I was an art student, and the story I told Ellis about making a hit with a cubist painting is true. That's what started the scheme of tattooing a picture message on my arm."
"Who suggested it?"
"One of the fellows who did the work. He was something of an artist as well as a chemist.
"The fellow with whiskers?"
"Yes," replied the spy. "I see you have had a pretty thorough report of that affair."
"We have. Did you know that the boy who was seized in the hall and dragged into the laboratory left with the pen-and-ink sketch of your painting crumpled up in his hand?"