The Twentieth Century

The measurement of time has never been more accurate! In 1929 the quartz crystal clock was developed. It was capable of an accuracy of 0.0001 second per day. A crystal of quartz is stimulated by a small electrical signal to vibrate. The quartz ensures this vibration is very accurate. The pulse from the vibration drives the clock mechanism.

Atomic clocks came in 1955. These vary by as little as 1 second in 3 million years! They are used all over the world to keep standard time.

The silicon chip revolutionised computers and electronics. It brought smaller, and smaller, clocks and watches.

Everyone, for the first time in history, has a means of telling the time. Few rely on public clocks any more.

What sort of watch do you think the arrow is pointing to?

Click the picture for an answer.