Bronze toads with open mouths and sickle: what they have in common

1. Step 1. Bronze toads with open mouths — is part of — Zhang Heng’s seismoscope. They catch the ball when it drops.
2. Step 2. Zhang Heng’s seismoscope — uses — Pendulum. An internal pendulum (according to reconstructions).
3. Step 3. Pendulum — is part of — Pendulum clock. The pendulum sets the period.
4. Step 4. Pendulum clock — has part — Gear. A wheel train.
5. Step 5. Gear — is part of — Lawn mower. The wheels turn the blade cylinder through gears.
6. Step 6. Lawn mower — evolved from — Sickle. Mechanized mowing.

Open Evothings