"So we have a fairly lucid book that describes the entire hook-up of the thing except what it's for. It gives not only the use of this device, but also variations and replacements. Could we figure it out by sheer deduction?" "I don't see how. The tower is in the midst of the Red Desert. There is nothing but sand that assays high in iron oxide between Canalopsis, at the junction of the Grand Canal and Lincoln Head. Might be hid, of course, just as this one was, and we'll send out a crew of expert sub-sand explorers with under-surface detectors to cover the ground for a few hundred miles in any direction from the place where we found this. Somehow, I doubt that we'll find much." "And how do you ... ah, there's the lights again ... deduce that?" asked Jim. "This gadget is or was of importance to the Martians. Yet in the Temple of Science and Industry at Canalopsis, there is scant mention of the towers." "Not very much, hey?" "Very little, in fact. Of course the pictographs on the Temple at Canalopsis shows one tower between what appear two cities. Wavy lines run from one city to the tower and to the other city. Say! I'll bet a cooky that this is some sort of signaling device!" "A beam transmitter?" asked Jim skeptically. "Seems like a lot of junk for just signaling. Especially when such a swell job can be done with standard radio equipment. A good civilization--such as the Martians must have had--wouldn't piddle around with relay stations between two cities less than a couple of thousand miles apart. With all the juice this thing can suck, they'd be more than able to hang a straight broadcast station and cover halfway around the planet as ground-wave area. What price relay station?" "Nevertheless, I'm going to tinker up another one of these and see if it is some sort of signaling equipment." * * * * * The door opened and Christine Baler entered. She waved a newspaper before her brother's eyes and said: "Boy, have you been missing it!" "What?" asked Barney. "Pixies or gremlins loose in Lincoln Head." "Huh-huh. Read it," said Jim. "Just a bunch of flash headlines. Fire on Manley Avenue. Three planes had to make dead-tube landings in the center of the city; power went dead for no good reason for about ten minutes. Façade of the City Hall caved in. Power plants running wild all over the place. Ten thousand dollars' worth of electrical equipment blown out. Automobiles stalled in rows for blocks." Jim looked at Barney. "Got a bear by the tail," he said. "Could be," admitted Barney. "Are you two blithering geniuses going to work all night?" asked Christine. "Nope. We're about out of ideas. Except the one that Barney had about the gadget being some sort of signaling system." "Why don't you fellows call Don Channing? He's the signaling wizard of the Solar System."