Creatures of Vibration

Carr Parker sat day-dreaming at the Nomad's controls. More than a week of Earth time had passed since the self-styled "vagabonds of space" had left Europa, and now they were fast approaching the great ringed orb of Saturn with the intention of exploring her satellites. Behind him, his Martian friend, Mado, was manipulating the mechanism of the rulden, that remarkable Europan optical instrument which Detis had installed in the vessel before they left. Mado was utterly fascinated by the machine, having spent most of his time during the voyage searching the surfaces of Saturn's moons for signs of human habitation.