The mind that noticed the cube would be drawn into it by the power of the disc, and would be sent on a thread of obscure energy to the place whence the disc had come -- the remote world of the worm-like space explorers across stupendous galactic abysses. Received in one of the machines to which each cube was attuned, the captured mind would remain suspended without body or senses until examined by one of the dominant race. Then it would, by an obscure process of interchange, be pumped of all its contents. The investigator's mind would now occupy the strange machine while the captive mind occupied the interrogator's worm-like body. Then, in another interchange, the interrogator's mind would leap across boundless space to the captive's vacant and unconscious body on the trans-galactic world -- animating the alien tenement as best it might, and exploring the alien world in the guise of one of its denizens.