Antimass

All craft of the type labelled Airship utilise some amount of what is known as Antimass. This is an array of one or more containers with large amounts of ionised liquid (typically heavy water) that is subjected to a hyper powerful, rotating electromagnetic field. The effect this has on gravitons leads to a negative weight proportional to the mass and the power supplied to the field, resulting in an upward lift far in excess of gasses lighter than air.

Antimass requires a large amount of energy to be supplied in order to maintain the effect, which is typically supplied by the airship's Vapour Drive. However, even without power the effect lingers long enough for an airship to stay afloat for some minutes as the electromagnetic rotation slows. The altitude of an airship is regulated by the electrical charge put into generating the electromagnetic rotation field. Antimass is much more powerful, but slower to respond. Cities use a different method of lift that is more stable but less controllable, called Floatrock.

The technology of antimass was such a cornerstone of Gold Age lifestyle that is was one of the few wonders from that time to survive and even remain somewhat ubiquitous.