Stopwatch
device · 1821 · Industrial Revolution
A watch for timing intervals.
What it is made of
- Balance wheel — has part. A balance wheel sets the pace.
- Mainspring — has part. A mainspring.
- Stopwatch crown button — has part. A cam starts and resets the hand.
Principles and materials it uses
- Brass — is made of. The stopwatch movement is brass.
What it is a kind of
- Pocket watch — is a kind of. A specialized watch.