So saying, he had resumed his calculations and had been engaged on them but a few seconds when the interruption occurred.
"Why, it's an idea I've been working out for some time, sir," said Ned modestly, in reply to the officer's question. "I'd rather like to have your opinion on it, sir, if it isn't too much to ask. You see, it's a scheme to attach pontoons to an aeroplane, making the machine practicable for both air and water. Inasmuch as our experiments are to select a naval type, it seemed to me that——"
"A machine that could fly and swim, too, if necessary, would be a great thing," broke in the officer enthusiastically. "Well, my boy, if you really have such an idea in practicable shape, I think I can encourage you to hope great things for it. Any one of a hundred manufacturers would be willing to buy your secret and pay you well for it, too."
Ned flushed. A flicker of something akin to indignation crossed his face.
"If it's any good, sir," he said quietly, "I intended that our navy should have it."
The officer brought down his hand with a hearty slap on Ned's broad shoulder.
"Good for you," he said. "I spoke as I did to test your motives in working on this invention, and I am not disappointed in you. If you will visit me at my quarters to-night, we'll talk more of the matter."
"Thank you, sir," rejoined Ned, flushing gratefully, and his eyes shining, "at what time, sir?"
"About nine o'clock. I've some friends coming over this evening and shall not be at liberty before that time."
Ned saluted, and Herc likewise clicked his heels together and raised his hand, as the officer left the hangar to resume his morning tour of inspection.