A glass-clear rod of water with no visible turbulence, produced by a long settling chamber and a honeycomb straightener that removes every trace of swirl before the water reaches the orifice. It reads as solid glass, and because the surface is optically smooth it will carry light down its length by total internal reflection — a single LED at the base lights the whole arc.
It is silent. There is no entrained air anywhere in the flight path, so the only sound the effect makes is where it lands, and a laminar rod entering still water makes almost none. This is why it is the first thing we reach for in hospitals, hotel lobbies, and anywhere a client says the word “calm” and means it.
The price is fragility. It is intolerant of wind above about 3 m/s, which is why it is an interior and courtyard effect. It is equally intolerant of dirt: a single leaf fragment lodged in the straightener turns the rod into a spray instantly and obviously, so a duplex strainer that can be cleaned without shutting down is not an upgrade, it is part of the effect. The settling chamber also makes the nozzle assembly long — typically 400 to 600 mm behind the orifice — which has to be in the architect’s section from the first week, not discovered at coordination.