Diatom

Splashery stretches a drumhead over this Splash's outline, twelve inches across, and finds the ways it can ring. Its lowest is 277.4 Hz, 99 cents flat of D4, 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 it to make the glass shell glint and open.

A diatom is a single-celled alga with a shell made of silica, the material in glass. Its patterned shell, called a frustule, has two overlapping halves, rather like a box and its lid. Diatoms live in fresh and salt water and use sunlight to make food, releasing oxygen.

Tap it and a glint of light runs across the glass, then the two halves lift apart to show the golden cell inside and close again; real diatoms don't open like this. Diatoms make about a fifth of the oxygen on Earth.

Made in Splashery. Its code is MIT.

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