The Clocks Museum
From sundials to optical lattice clocks — the engineering and history of how humanity learned to measure time. Build a pendulum, animate four historic escapements, and trace 5,500 years of innovation.
Pendulum Clock
A weight-driven movement with a 0.248 m pendulum beating once a second (the "seconds pendulum" of Huygens, 1657). Adjust the bob length, change planets, watch the period and frequency respond to T = 2π√(L/g).
The Collection
40 artifacts spanning 5,500 years of timekeeping — from Egyptian shadow clocks to optical lattice clocks accurate to 10⁻¹⁹. Click any card to copy its description.
No artifacts in this category.
55 Centuries of Time
Key milestones from 3500 BC to the 2010s — scroll to trace 5,500 years of timekeeping innovation.
Escapement Visualizer
The escapement is the heart of every mechanical clock — it controls the release of energy from the driving weight or spring, one tick at a time. Four historic types, four very different sounds.
Verge & Foliot (~1300) — the earliest mechanical escapement. A crown wheel's teeth push alternately on two pallets.
Hands-on Instruments
Calculate a custom pendulum's period under any gravity, chain three gear stages and read out the train ratio, compare time zones across a globe.
Before railways, every town kept its own local solar time. The 1884 International Meridian Conference standardized 24 time zones from Greenwich.