"Well, anyway, by the use of suitable fields of force it can be used as a carrier wave. Most of this stuff of the fields of force--how to carry the modulation up and down through all the frequency changes necessary--was figured out by the Martians ages ago. Used as a pure carrier wave, with a sender and a receiver at each end, it isn't so bad--that's why our communicator and radio systems work as well as they do. They are pretty good, really, but the ultra-light vision system is something else again. Sending the heterodyned wave through steel is easy, but breaking it up, so as to view an object and return the impulses, was an awful job and one that isn't half done yet. We see things, after a fashion and at a distance of a few kilometers, by sending an almost parallel wave from a twin-projector to disintegrate and double back the viewing wave. That's the way the lookout plates and lenses work, all over the ship--from the master-screens in the control room to the plates of the staterooms and lifeboats and the viewing-areas of the promenades. But the whole system is a rotten makeshift, and...." "Just a minute!" exclaimed the girl. "I and everybody else have been thinking that everything is absolutely perfect; and yet every single thing you have talked about, you have ended up by describing as 'unknown,' 'rudimentary,' 'temporary,' or a 'makeshift.' You speak as though the entire system were a poor thing that will have to do until something better has been found, and that nobody knows anything about anything! How do you get that way?" "By working with Brandon and Westfall. Those birds have got real brains and they're on the track of something that will, in all probability, be as far ahead of Roeser's Rays as our present system is ahead of the science of the seventeenth century." "Really?" she looked at him in astonishment. "Tell me about it." "Can't be done," he refused. "I don't know much about it--even they didn't know any too much about some of it when I had to come in. And what little I do know I can't tell, because it isn't mine." "But you're working with them, aren't you?" "Yes, in the sense that a small boy helps his father build a house. They're the brains--I simply do some figuring that they don't want to waste time doing." Nadia, having no belief whatever in his modest disclaimer, but in secret greatly pleased by his attitude, replied: "Of course you couldn't say anything about an unfinished project--I shouldn't have asked. Where do we go from here?"