How to use a Slide Rule Bezel on your Watch. Watch and Learn #11

In today's episode of Watch and Learn, we show you how to use the rotary slide rule on a watch. Often referred to as an aviation slide rule, this indispensable tool is the pre-cursor to modern calculators. From dividing up a dinner tab among friends, then adding a tip, to calculating fuel consumption on a weekend flight, these little machines can do it all.

The rotary version of the slide rule uses the same principles of the linear slide rule that some engineers still use today. Employing the Logarithm function, they make easy addition out of complex multiplication problems. With just a little know-how, and a few minutes watching this video, you will find out how to unlock the potential of this awesome tool strapped to your wrist, like converting kilograms to pounds, miles to kilometers, etc.

This video uses the Seiko Flightmaster SNA411P watch, but the principles apply to any slide rule watch, from the Breitling Navitimer to the Citizen Blue Angel watch.

To see some of the watches we offer with the rotary slide rule, please visit: longislandwatch.com/shop/?search=slide+rule