lessly. "So, incredible as it may appear, he was one of the guests. This Mr. X. came to the dance wearing the aviator's costume, or most of it, underneath his masquerade costume. When he was ready to act, he doffed his outer costume, appeared as the Midnight Masquer, effected his purpose, then calmly donned his outer costume again and resumed his place among the guests. You understand?
"Well, then! Maillard yesterday received a note from the Masquer, brazenly stating that he intended to call during the evening. I have that note. It was written with an extremely hard lead pencil, such as few men carry, because it does not easily make very legible writing. Last night I asked Mr. X. for a pencil, and he produced one with an extra hard lead—mentioning that he had borrowed it from Bob Maillard, as indeed he had."
"What! Surely, you don't mean"
"Of course I don't. Mr. X. is very clever, that's all. Here is what took place last night. Mr. X. brought us another note from the Masquer, saying that he had found it pinned to the library door. As a matter of fact,
