One night, long ago, a band of drunken astro-engineers of the first generation clambered round the building digging this, fixing that, banging very hard on the other and when the sun rose the following morning, it was startled to find itself shining on a building full of happy drunken people which was now floating like a young and uncertain bird over the treetops.
Not only that, but the flying party had also managed to arm itself rather heavily. If they were going to get involved in any petty arguments with wine merchants, they wanted to make sure they had might on their side.
The transition from full-time cocktail party to part-time raiding party came with ease, and did much to add that extra bit of zest and swing to the whole affair which was badly needed at this point because of the enormous number of times that the band had already played all the numbers it knew over the years.
They looted, they raided, they held whole cities for ransom for fresh supplies of cheese crackers, avocado dip, spare ribs and wine and spirits, which would now get piped aboard from floating tankers.
The problem of when the drink is going to run out is, however, going to have to be faced one day.
The planet over which they are floating is no longer the planet it was when they first started floating over it.
It is in bad shape.
The party had attacked and raided an awful lot of it, and no one has ever succeeded in hitting it back because of the erratic and unpredictable way in which it lurches round the sky.
It is one hell of a party.
It is also one hell of a thing to get hit by in the small of the back.