"Just why do you say 'she' when you speak of the writer?"
"Oh, I have an idea that Mrs. Neumann may be the mysterious friend who is taking such desperate chances to send you a warning. Anyway, something about it seems to say it isn't a man's handwriting. Besides, neither of you may have noticed it, but there's a faint odor, as of perfume, adheres to that bit of paper, though the dampness has taken it almost all out."
Jack looked astonished at such shrewd reasoning.
"Well, you are certainly a wonder at seeing through things, Tom," he hastened to say. "And so of course that settles it in my mind. Mrs. Neumann sent this message to me; though how she could have learned that there was anything treacherous going on beats my powers of reasoning."
"But don't you think it would pay to learn if there's any truth about it all?" asked the other pilot, whose curiosity had been stirred up by such a strange happening.
"Yes, let's all go over to the hangars and have the planes out for a regular inspection," said Tom. "If mischief has been done the chances are it would be in a part not usually examined by the mechanician before a flight. Then again the damage, if there is any, might be so covered up by the shrewd schemer that it would not be noticeable."
There were always cars going to and fro, for pilots came and went from time to time; so the trio quickly found themselves being whirled along over the road so often traveled in their daily work.
"How about that fellow they chased late yesterday afternoon, who was loitering about the hangars and acting in a suspicious way?" asked the friendly pilot, as they rode along. "More than a few of the fellows say he must have been a spy, and up to some mischief, because he slipped off so slickly."
"I had him in mind all the while," said Tom. "And if any mischief has been done, of course we can lay it at his door; though just how he managed to work we'll perhaps never know."
"I caught sight of him, too," Jack remarked; "and I only wish now I'd had a good look at the chap who owned those pigeons to-day, so as to tell if they were one and the same, which I believe to be a fact."