He completed the application of India ink to the drawing of a seaplane body, in outline, showing the many braces and their points of attachment to the longitudinal “keel.”

He put it away, with others, in a folder when it was dry.

“I guess knowing about designs won’t help, any more than knowing how to fly a ship was of any use to the Airlane Guard,” he murmured, laying the folder aside for Garry’s later use.

“If we only had the ‘ignition key’ so we could make ‘contact,’” he smiled at his application of aviation terms to their puzzle, “it would be easy to give it the gun and fly a straight course to the solutions.”

When dusk came on and the chums gathered to compare notes, the day proved to have yielded blanks all around.

“The Indian told the truth,” Garry reported. “Your uncle has engaged a private detective and he checked up. John and old Ti-O-Ga are ‘playing a split week’ engagement at the Palace, starting Saturday—today. The helicopter hasn’t been moved. A private detective is there, watching it, and one is in the hangars.”

“We can go to the movies, then,” suggested Don. “Let’s see if the old ‘medicine man’ meant anything by giving us passes, and telling us to take them out of the bag after seven days.”

“He might, at that,” Garry became more animated. “That connects up, because after seven days he knew he would be here, with his son.”

“I hadn’t seen it that way,” responded Don. “Let’s go!”

They found the Palace, on a side street, fairly filled when they presented the three yellow slips to the door man. Large “cut-out” figures of Indians, in various poses, and posters, from “one-sheets” to “flash twenty-four sheets,” decorated the theatre and billboards nearby, showing in blatant coloring the scenes from “Red Blood and Blue.”