Watches are the most advanced mechanical devices that can still be made by hand. To me, they are essential for keeping time on my tours and when I'm swimming. My first watch was a Seiko digital watch and I still prefer them today. But I have a deeper appreciation for analog watches after reading Hands of Time by horologist Rebecca Struthers. She traces the history of portable and wearable timepieces from the prehistoric Lebombo Bone to the development of mechanical and automatic watches. She ends the book with an account of how a watch is repaired.
My favorite timekeeper is the ring dial:
"engraved metal rings that could be held up to the sun and read as the light shine through a small hole in the main band and cast a bright dot on a scale inside."