Jack in turn became aroused.
"A homing pigeon, is it?" he ejaculated. "Why, birds like that are used for carrying messages across the lines! Some of our airplane pilots have told me that sometimes they take a French spy far back of the German front. When he had made an important discovery he would write a message in cipher, enclose it in a tiny waterproof capsule attached to a ring about the pigeon's leg, and set the bird free. Inside of half an hour it would be safe back in its loft, and the message on the way to French headquarters."
He lifted one limp leg, and then the other.
"Look here, it's got a message, as sure as anything!" Jack exclaimed.
Tom leaned forward and took the bird in his hand, dropping the gun meanwhile. He carefully took off the gelatine capsule, and from it extracted a delicate piece of tough paper, which he spread open. There were a series of strange marks on the paper, of which neither of the air service boys could make anything.
"Looks like hieroglyphics, such as you'd expect to find on an Egyptian tomb or in the burial places under the pyramids," complained Jack, after he had stared at the lines in disgust for a brief period of time.
"It's a cipher of some kind," explained Tom, seriously. "With the key all this would resolve itself into some sort of communication, I suppose, connected with valuable information concerning the French armies here at Verdun."
"Then it was made by a spy!"
"No question about that part of it," came the ready reply.
"This carrier pigeon with this message, was on its way across to some point in the rear of the enemy line when you fired, and brought the poor little thing down in a quivering heap, I'm sure that's it," continued the other.