The earliest people divided time into two intervals, nighttime and daytime. Today’s atomic clocks divide time into picoseconds—trillionths of a second! How did we get from there to here?
This detailed examination of the art of telling time spans cultures, technologies, and, of course, centuries. Children will discover which Egyptian god governs time measurement and what it is inside a mechanical clock that makes it go “tick-tock.”
Learn how the 12th century “verge and foliot” came to be replaced by the 17th century pendulum, and eventually by 20th century quartz crystals and microcircuits!
Thorough, in-depth explanations of clock technologies are presented in their historical context and paired with illustrative diagrams. Hardcover, 32 pages. Ages 8 and up.