"A new invention. Just perfected a few weeks ago, I understand. By Ludwig Von der Valls, the German physicist." "I've quit bothering about science. It has ruined nature, filled the world with silly, artificial people, doing silly, artificial things." "But this is quite remarkable, dear. A new way to travel--by ether!" "By ether!" "Yes. You know of course that energy and matter are interchangeable terms; both are simply etheric vibration, of different sorts." "Of course. That's elementary." She smiled proudly. "I can give you examples, even of the change. The disintegration of the radium atom, making helium and lead and _energy_. And Millikan's old proof that his Cosmic Ray is generated when particles of electricity are united to form an atom." "Fine! I thought you said you weren't a scientist." He glowed with pride. "But the method, in the new Cosmic Express, is simply to convert the matter to be carried into power, send it out as a radiant beam and focus the beam to convert it back into atoms at the destination." "But the amount of energy must be terrific--" "It is. You know short waves carry more energy than long ones. The Express Ray is an electromagnetic vibration of frequency far higher than that of even the Cosmic Ray, and correspondingly more powerful and more penetrating." The girl frowned, running slim fingers through golden-brown hair. "But I don't see how they get any recognizable object, not even how they get the radiation turned back into matter." "The beam is focused, just like the light that passes through a camera lens. The photographic lens, using light rays, picks up a picture and reproduces it again on the plate--just the same as the Express Ray picks up an object and sets it down on the other side of the world. "An analogy from television might help. You know that by means of the scanning disc, the picture is transformed into mere rapid fluctuations in the brightness of a beam of light. In a parallel manner, the focal plane of the Express Ray moves slowly through the object, progressively, dissolving layers of the thickness of a single atom, which are accurately reproduced at the other focus of the instrument--which might be in Venus! "But the analogy of the lens is the better of the two. For no receiving instrument is required, as in television. The object is built up of an infinite series of plane layers, at the focus of the ray, no matter where that may be. Such a thing would be impossible with radio apparatus because even with the best beam transmission, all but a tiny fraction of the power is lost, and power is required to rebuild the atoms. Do you understand, dear?" "Not altogether. But I should worry! Here comes breakfast. Let me butter your toast."