Downline

Downline, often abbreviated to 'line', is the common trade name for cables made of morphic polyxylene. Although it has uses in cleaning, electronics and more recently in hydroponics, for most people line is a term synonymous with orbital engineering.

The advanced complexing structure in a length of line results in a cable whose physical properties are effected by the presence of strong electrical fields. Typically, a field perpendicular to the line causes it to become rigid. A field along the direction of the cable causes the normally strong fibres to stretch and snap like strings of unspun cotton. However, both of these changes are found to be negated by a current flowing along the wire, which increases both its flexibility and its (already impressive) tensile strength.

If one end of a length of current-carrying line is immersed in certain ionic solutions, anions may be carried along the length of the cable and form protective complexes at any weakpoints where the cable has been damaged. This self-repairing property makes downline almost uniquely suited for tough conditions such as use in ground-to-orbit elevators and scattered world moorings.