“Yes; and without the ‘juice’ turned on. Jove! We didn’t realize how much reserve power of propulsion we had. It’s well that I experimented first with the minimum. And the current almost quadruples the magnetism of mythonite! Phew!” Robert paused and read the altimeter again. Eight thousand. He gripped the gyrostatic control, and carefully moved it to half speed. The _Sphere_ seemed to pause a moment, then they could detect its beginning to settle earthward as the neutralization of gravity was modified. Six thousand; five thousand; they were dropping steadily at a rate of nearly a thousand feet a minute. Robert shoved the lever back to full speed and the _Sphere’s_ downward momentum was quickly checked. With the disk safely throttled, the _Sphere_ became as a rubber balloon. They merely drifted in midair. Together they peered through the observation well in the floor. Through this they could plainly see the landscape, some three thousand feet below, sliding by sluggishly as they drifted with the light air current. From the side ports they could discern the big Palmer homestead and the laboratories about a mile and a half to the west of them. It was an ideal day for observation. The sky was cloudless, and the air of crystal clearness. “Well, professor, shall we run back to our stall, or take a little sight-seeing jaunt?” queried Robert. “Let’s see some of the country, by all means,” decided the professor, his face aglow with boyish excitement and anticipation. “All right; here goes,” Robert sang out as he deflected the disk to a horizontal position, pointing due north. The next instant he switched open the first shutter from the disk’s surface. There was a jerk, and the landscape suddenly began slipping away to the south with accelerating speed. Another click, and their speed was further increased. Once more the switch clicked, releasing the last shutter from over the disk. The _Sphere_ seemed literally to leap ahead. A muffled roar without indicated the great speed at which they were rushing through the air. Town after town flashed by beneath them with astonishing rapidity. The fact that they were flying at a comparatively low altitude made their speed seem terrific. Robert wisely decided to seek a safer height. He elevated the disk several degrees and the _Sphere_ promptly soared higher. At eight thousand feet he checked its upward trend. Far away to the east they could see a solitary big biplane bound in the same direction as they--probably a fast mail express; but it was quickly left behind, and lost from view in the afternoon haze. For twenty minutes they roared northward. Then, to their surprize, a vast body of water appeared against the horizon ahead. “Lake Erie!” gasped Robert, after a moment’s reflection. “Two hundred miles in less than half an hour. Why--that’s about five hundred miles an hour! And without the aid of electric magnetization of the disk!” “Marvelous!” exclaimed the professor, enthusiastically.