Mystery Object #8 ANSWER

About

Ever wonder how a rotary telephone works, how sailors and pilots navigated by the stars, or how mechanical calculators perform complex math using only gears? Then you've come to the right place! Our Own Devices is a channel dedicated to the fascinating world of vintage technology, and the many elegant and ingenious ways our ancestors solved even the most complex technical problems. Want more fascinating history? I am a regular staff writer for Today I Found Out and many of its sister channels: https://www.youtube.com/@TodayIFoundOut I also have a historical adventure novel titled 'Our Own Devices' set in 1920s Morocco. Check it out at my personal website: www.gillesmessier.ca And finally, I make 1920s/30s-style Art Deco posters, which you can purchase on my Etsy store: https://www.etsy.com/ca/shop/DecoEchoes