As for the sudden departure of Hank and Miles Sharkey, that was more understandable. They had practically hired Sam to make his desperate attempt to cripple the Electric Monarch, and knew that their plans must have been foiled when they saw the craft take to the air. This being so, they had probably argued that Sam would be arrested and would implicate them. Flight, then, must have seemed to them to be their wisest course.
And so, for the present, the mystery of the stolen plans had to be given up by the police and those most interested in the recovery of the papers, as an unsolvable puzzle. Of the startling way in which it was to be cleared up, none of those concerned had the slightest inkling. From day to day the boys feared to hear of the plans being filed in the patent office. But, although through Prof. Chadwick’s patent lawyers in Washington, they kept in constant touch with the National Capital, no such papers turned up. In the meantime the boys busied themselves making as complete a set of duplicate plans as possible, covering every patentable feature of the Electric Monarch.
Two days after the mysterious disappearance of the plans of the Electric Monarch the promised entry blanks for the Aëro Carnival at Portstown arrived. Inclosed with them the worthy captain had sent a copy of a Portstown newspaper in which there was announced in flaring capitals the following:
“Captain Abe Sprowl, in charge of the Aëro Carnival, announces that he has engaged, at unprecedented expense, the newest marvel of the air, the motor-driven hydroaeroplane, The Electric Monarch, owned and invented by Ned Nevins, the youthful inventor. The machine will make a flight from Nestorville to the show grounds, and will be on view daily during the carnival.”
“Well, what do you think of that?” gasped out Jack, as he read this flamboyant announcement out aloud to his companions. “As a press agent Captain Sprowl is certainly a wonder. It looks as if we’d have to go now, boys, doesn’t it?”
“It sure does,” agreed Tom, “but I wish he hadn’t run that fool notice. We don’t want all that notoriety just now.”
“No, indeed. Not till the plans are all safely filed in the patent office,” agreed Ned, with a serious look. “Queer, that whoever took the other set hasn’t tried to place them on record yet, isn’t it?”