This helped catapult them to the industry forefront.
At this time watches were typically four or five inches wide and about three inches thick.
They are sought by collectors and Civil War buffs and re-enactors, says Eric Engh, co-owner of the website the world's largest seller of pocket watches on the internet.
Walthams, in particular, are very collectible," he said.
Today, the number of jewels a watch has is a sign of its quality and durability.
Finding a pocket watch made prior to 1700 is rare these days. Antique watches crafted before 1865 are very popular.