Tide

keep beating. it only moves because you do.

be the heart — tap a rhythm and drive one red cell around its full lap

Blood loops the body in a figure eight, not a circle, since the lung loop and the body loop both start and end at the heart, crossing there. It only moves because the heart keeps pushing: stop the rhythm and the lap slows, coasts, and stalls.

Concepts: circulation, biology.

An interactive you play with one thumb, on Wundr.