What power is it that drives the ship?
Is it lighter than air, or what ?" "Well, you see the entire framework of the ship is hollow.

Every single thing you see--even the chairs and tables--they're all made of the metal _aerolite_ (as it's generally called).

It's almost as thin as paper, and it's far stronger than any steel.
Now it's the framework of the ship that takes the place of the old balloon.

It's infinitely safer, too, for it's divided by automatically closing stops into tens of thousands of compartments, so a leak here and there makes practically no difference.

Well, when the ship's at rest, as it is now, there's simply air in all these tubes; but when it's going to start, there is forced into these tubes, from the magazine below, the most volatile gas that has been discovered----" "What's it called ?" "I forget the real name.