I just heard from my chums at SiTime saying that they are sharing an eBook they’ve written called The Story of Timekeeping.

The Story of Timekeeping (Click image to see a larger version)

If you visit The Story of Timekeeping link and then click on the “Enter the Timeline” button, you will be presented with a nicely implemented interactive timeline that commences with Stonehenge and makes its way through sundials, water clocks, candle clocks, hourglasses, and mechanical clocks, to quartz clocks and… the list goes on.

The main thing to note is the “Download eBook” link in the upper right-hand corner of the page. The resulting 70-page eBooklet boasts nine chapters as follows:

Chapter 1: The Origins of the Measure of Time
Chapter 2: The Dawn of Timekeeping
Chapter 3: The Oscillator
Chapter 4: Chronometry
Chapter 5: Longitude
Chapter 6: Civil Time
Chapter 7: Quartz Oscillator Timekeepers
Chapter 8: Atomic Clocks
Chapter 9: Contemporary Applications of Precision Timekeeping

This little scamp is replete with nuggets of knowledge and tidbits of trivia. I soon spotted some old favorites, such as Saint Augustine of Hippo who famously said, “What then is time? If no one asks me, I know what it is. If I wish to explain it to him who asks, I do not know.”

I know how he felt.

I knew that the earliest sophisticated timekeepers were water clocks, also known as clepsydra. However, I wasn’t aware that the Su Song Water Clock in China circa 1100 AD had an estimated possible accuracy of 1 second/day.

Also, although it wasn’t mentioned in this eBook, I knew that one of the first known automatic water clocks was devised in Korea circa 1434 AD. This clock was called Chagyongnu, which literally translates as “self-striking water clock.” When the water reached a certain level, a trigger device released a metal ball, which rolled down a chute into a metal drum to “gong the hour.”

All in all, the folks at SiTime have managed to cram a lot of interesting and useful information into this book. This is one that I will keep as a handy-dandy reference guide for the future. How about you? Are there any time-related factoids you’d care to share with the rest of us?