The doctor took the slip into his own hands and read the message gravely.
"Where did you get this?"
Burton told him the night's adventures in outline, mentioning casually Henry's return to the house at two, and the subsequent attempt of some one to enter his room, and his ineffectual pursuit.
Dr. Underwood listened with a more impassive face than was altogether natural. At the end of the recital he picked up the slip of paper again and studied it.
"I think one of those handwriting experts who analyze forgeries and that sort of thing would say that this was my handwriting, somewhat disguised," he said.
"Yours!" Burton exclaimed, taken by surprise.
"That's what struck me at first sight,--its familiarity. It is like seeing your own ghost. Of course it is obviously disguised, but some of the words look like my writing. You see how I am putting myself into your hands by this admission."
Burton fancied he saw something else, also, and the pathetic heroism of it made his heart swell with sudden emotion.
"A clue!" he cried gaily. "You did it in your sleep! And you wrote those typewritten letters and handbills on the typewriter in your surgery, when you were in the same somnambulic condition! I examined the work of that machine this morning. It corresponds so closely with the sheet you showed me last night that I have no doubt an expert would be able to work out a proof of identity."
"I'll see that the room is locked hereafter at night," said the doctor, with an effort.