It was apparent that his coming had not yet been noticed, since he had cut off the plane's motor high above, and no one had yet emerged from the buildings about him. He glanced around them uncertainly, then started across the open clearing toward one at the opposite side, from whose door and windows came the white light he had glimpsed from above. Half-way across the clearing, though, he slowed, came to a stop. He had halted before the great object at its center which he had but vaguely glimpsed from above, but which now, looming a few feet before him, was so extraordinary in appearance as to turn all his interest and attention upon it for the moment. It was a great globe, a giant sphere of burnished metal fully fifty feet in diameter, resting upon a massive metal pedestal that had been sunk into the rock. From the top of the great globe a thin, needle-like rod of metal, tapering to a point, projected perpendicularly upward, while from the pedestal-base a network of connections ran to some two or three of the long, low buildings about the summit. From these buildings came the throbbing of unceasing mechanisms of some sort, but from the globe itself arose only a fine, incessant hum, hardly to be heard, though giving to Ralton in some way an impression of terrific power. At the point where the myriad black-covered connections ran into the globe's base there rose beside it, on a tripod of metal standards, a box-like black-gleaming object upon whose face were set a dozen or more glass-fronted dials, their needles trembling with the power racing through them; a series of switches and automatic circuit-breakers; and a single bulbous black knob which moved up and down a vertical slot in the switch-board, apparently. The sides of that slot, Ralton saw, were finely graduated, the knob-lever resting almost at its bottom. Near the slot's top small white letters inset beside it spelled "Ultra-Hertzian Vibrations." An inch or so beneath, beside the slot in similar lettering, was "Hertzian Vibrations." Beneath that, in turn, "Light Vibrations," "Heat Radiation Vibrations," "Radio-active (Gamma) Vibrations," then "Cosmic Ray Vibrations," at which the black switch-knob rested, and lowest of all a simple zero. Ralton stared at the thing in astonishment. It was the entire range of etheric vibrations that was lettered in order there before him, he knew, from highest to lowest, but for what reason? This great globe-mechanism, what could biologists be doing---- A cry from behind whirled him about, a cry of fierce rage from the door of the white-lit laboratory building beyond him. Framed in that doorway stood a massive-figured, gray-haired man, eyes burning and face contorted as he saw Ralton, while from the white-lit room behind him other figures were surging forward.