Astounding Stories, March, 1931
He came slowly beside it to study the box with narrowed eyes. He expected the metal cover would be as immovable as the others, and he started back and caught his breath sharply as the metal raised at his touch and the green radiance from above flashed back from within the box in a thousand scintillant lights. Then he stooped to see the brilliant, silvery sheen of metal wheels that moved on jeweled bearings.
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A mechanism of some sort--but what? he wondered. He had some knowledge of the stream of electrons that discharged continuously from the light above, and he knew how they could charge an electroscope that would automatically discharge to produce motion. He nodded in half-understanding as the fluttering gold-leaf fell and allowed a tiny wheel to move one notch in its escapement.
"Clockworks!" he told himself--it was as near as he could come to a name for the machine--"and it's been running here all this time.... What for, I wonder? What was