Klein Bottle

Splashery stretches a drumhead over this Splash's outline, twelve inches across, and finds the ways it can ring. Its lowest is 550.0 Hz, 86 cents sharp of C5, the nearest tine on the comb. The next fifteen are its overtones, and each one draws its own figure: sand gathers on the lines that stay still.

Tap to send water through. Set the glow in the Splash tab.

A Klein bottle is a surface with no inside and no outside. Its neck bends around and passes through its own side to join the bottom from within, so an ant crawling on it could reach every part of it without ever crossing an edge. Felix Klein described it in 1882. A true Klein bottle needs four dimensions; in our world its neck has to cut through the wall.

Tap it and a surge of glowing water pours in at the base, runs up the body, through the neck and around into the bottom, then fades. Set the glow, or pick the color of the glass, in the Splash tab.

This link opens it in the Playground. To put it on your own page, add the element and one script tag. Every option.