The superfluid fountain was the centerpiece of the Garden. It was based on a clearwood cylinder twenty microns across, fixed to a tall, thin pedestal. Inside the cylinder hovered a rough ball of gas, stained purple-blue, quivering slowly. The cylinder — fabulously expensive in itself, of course — was girdled by five hoops of polished Corestuff, and it bristled with poles which protruded from its surface. Barrels — boxes of wood embossed with stylized carvings of the heads of Hork IV and his predecessors — were fixed to the ends of the poles inside the cylinder.

Beautiful young acrobats — male and female, all naked — Waved spectacularly through the Air around the cylinder, working its elaborate mechanisms. The electric blue of the vortex lines cast shimmering highlights from the clearwood, and the soft, perfect skin of the acrobats glowed with golden Air-light.

The upfluxer, Adda, made a disgusting noise through his nose. "You brought me here to see this?"

Muub smiled. "I wouldn't expect you to understand what you're seeing."

Adda scowled, his hostility evident. "Then tell me."

"Superfluidity." Muub pointed. "The cylinder contains a low-pressure region. There's hardly any Air in there, I mean... except for the sphere in the center. That's just Air, but stained blue so you can see it. The hoops around the cylinder, there, are generating a localized magnetic field. Do you understand me? Like the Magfield, but artificial. Controllable. The magnetic field keeps the cylinder from being crushed by the pressure of the Air outside. And it's designed to keep the little Air inside the cylinder in that ball at the center."

"So what?"

"So we can view the Air — within which we are ordinarily immersed — from the outside, as it were.

"Adda, Air is a neutron superfluid — a quite extraordinary substance which, were inhabitants of some other world to discover it, would seem miraculous. Quantized circulation — the phenomena which causes all the spin in the Air to collect into vortex lines — is only one aspect. Watch, now, as the vessels are lowered and raised from the sphere of Air."

A handsome young acrobat — a girl with blue-dyed hair — grasped one of the poles protruding from the cylinder and pushed it through the clearwood wall. The base of the ornate barrel at its far end dipped into the sphere of blue Air. The barrel wasn't completely immersed; the girl held the barrel still so that its rim protruded from the surface of the Air by a good two or three microns.

Blue-stained Air visibly crawled up the sides of the box and over the lip, pooling inside. It was like watching a living creature, Muub thought, fascinated and charmed as always by the spectacle.