"There are two letters, sort of twined together," answered Matt. "I make them out to be 'G. F.,' although I——"
An exclamation escaped Cameron.
"Let me see it!" he cried, stepping forward and showing an astonishment and eagerness which bewildered Motor Matt.
For several minutes Cameron turned the blade around and around in his hands, staring in amazement and muttering to himself.
"Will you let me have this for a little while, Matt?" asked the lieutenant when he had finished his examination. "This may be a most remarkable find—remarkable as well as of tremendous importance. I can't tell about that, though, till I have a talk with some of the others at the post."
"Of course you can take it," said Matt. "But what makes that rusty piece of steel so important?"
"I'll tell you—later."
Thereupon the lieutenant whirled in his tracks and made off at speed in the direction of the post.
McGlory had been under the aëroplane fitting in the pipe that led from the tank to the carburetor. He had overheard the talk, however, and had caught a glimpse of the dagger while the lieutenant was examining it.
"Tell me about that!" he exclaimed, crawling out from under the aëroplane. "There was something about that rusty old knife that knocked Cameron slabsided. What do you think it was?"