 How do humans perceive the transportation devices?
A gray, funnel-shaped cloud of dust stood off to his left. But then, how could a group of loosely spaced grains of sand possibly have a nervous system? From one angle they were animals, from another birds, from a third they were vaguely humanoid creatures, glowering at him with primitive ferocity. These creatures were not only humanoid, but definitely human, although more slight of build than earth people. But up to now the tube and the chain was the only evidence of an advanced technology, unless the ancient inscriptions in the stone wall of the pool, and the statues lining the wall were evidences. An object like a pallet was brought, carried by four of the women.
 They are luxury goods that many have strong independent motivation to acquire
 They are only used to transport between worlds but humans wish they could be used for local travel  They are untrustworthy technology that are dangerous to implant  They are luxury goods that many have strong independent motivation to acquire  They are commodities in the current economy