Of course, as soon as the frames were bolted on on either side and the weight was equalized, the aeroplane balanced on her pontoons and there was no need for artificial support. Getting the engine in place came next, and for a time seemed to promise serious difficulties; but this problem was finally solved by towing the pontoon-supported air-ship alongside the Bolo, and then using her main boom as a derrick. Billy Lathrop and Ben Stubbs hauled on a tackle attached to the engine, and thence to the end of the boom, and the heavy bit of machinery swung outboard without a hitch. It was then an easy matter to lower the motor on to its bed, which had been previously set in place. It didn't take long to bolt the engine down, lay the propeller bearings and set the main shaft and its twin connections in place and "true" them up. The last work, before adjusting the tanks for gasolene and oil, was to affix the propellers themselves. This was accomplished by erecting a rough stand on a platform of the cabin floor boards.
At last everything was pronounced ready for a start and the finishing touches were completed. Harry even lovingly touched up some scratched places about the frame with the contents of a paint-pot he had found in a locker.
It was at this point that Billy Barnes made a great discovery.
"But say, Frank," he exclaimed, "when you start the propellers she is going to fly even though you may want her to skim the water."
"Is she, mister know-it-all?" laughed Frank, "that shows all you know. See this pump?" He indicated a small centrifugal affair geared to the main shaft.
Billy nodded.
"Well," explained Frank, "when we want to keep the Golden Eagle down on earth, or rather sea, we fill the pontoon tanks to the necessary weight with this pump. When I want to rise, I pump the water out again."
"Gee, that's simple—like all your ideas, Frank," said the admiring
Billy.
"When are we going to try a trial trip?" demanded Lathrop.
"No reason why we shouldn't start right away on one," declared Frank, "if you fellows will bear a hand and fill up the gasolene, radiator and lubricator tanks."