The air supply was manufactured by chemical means on board, but very little was needed, as the original supply taken from the earth is used over and over by altering the carbonic acid gas by means of automatic generators.
It was of course of the utmost importance that no port-hole or doors leading to the outside be opened. The air would have rushed from the flyer instantly, resulting in a perfect vacuum inside of the flyer, and instant death to all living organisms.
As the flyer moved away from a celestial body, the less the mechanical energy needed to propel it. There were of course exceptions. Thus between every two celestial bodies a point will be found where the attraction that one body exerts on the other is zero. If the flyer were brought to this point its gyroscopes could be at rest, as the machine would not be attracted by either body. It would "hang" between the two just as an iron ball hangs between two powerful magnets if carefully balanced. Give it the slightest push, however, and the ball will fly to either of the magnets.
The same was true of a space flyer, between two bodies at the "zero point." If it moved over that point it was immediately attracted by one of the bodies, and if its gyroscopes refused to work, the flyer would have been dashed to pieces against the attracting body.
If, however, the machine came to rest at the "zero point" it would begin to turn around on its own axis, while at the same time moving in an elliptical orbit around the sun--_the space flyer would become a tiny planet_, and as such was subject to the universal laws of the planetary system.
It was not hard to steer the space flyer; the nearer it came to a celestial body, the faster the gyroscopes worked; the further it drew away, the slower their movement.
After Ralph had thoroughly inspected the entire flyer he devoted his full attention to the course of Fernand's machine. At the rate at which he was flying he computed that he would overtake Fernand in ten hours, provided the latter did not increase his speed meanwhile.
Fernand, when Ralph left Earth, had a handicap of 400,000 miles. He was moving at the rate of 45,000 miles an hour. Ralph's machine had made 80,000 miles an hour since its start. If everything went well he would overtake the other in ten or eleven hours.