Every part of the great room was plainly visible, and not a living being was even watching that vast instrument-board. "What do you make of it, Dick?" asked Crane, slowly. "No wiring tight beam transmission. The Fenachrone do it with two matched-frequency separable units. Millions and millions of kilowatts there, if I'm any judge. Absolutely automatic too, or else " Seaton's voice died away.

"About as doubtful as the radio I think that I could build a pair of matched-frequency auto-dirigible transmitter and receptor units, such as are necessary for space-ships fed by stationary power-plants, but after I got them built, they'd take us less than half way there. Then we'd have only what power we can carry, and I hate even to think of what probably would happen to us.

The individual transmitting fields and receptors are really simply matched-frequency units, each matching the electrical characteristics of some particular and unique beam of force. This beam is composed of Roeser's Rays, in their energy aspect. It took a long time to work out this tight-beam transmission of power, but it was fairly simple after they got it."