Expert: Melvin Mills - 7/31/2007

Question
what can you tell me about a wrist watch with a hindge back,inside the back is s.w.c.co. gold filled 20 years 10 and a half ligne 4718669 on the movement parts reads 15 jewl 2 adj fidelis.w.co.....any info. would be great. thanks ~T~

Answer
Gold filled 20 years means that the gold was guaranteed not to wear through to the base metal for 20 years.

Ligne is a French word meaning line. It was in use prior to the French adaptation of the metric system in the late 1700s, and is still used by French and Swiss wristwatch makers to measure the size of a watch movement.
The standardized conversion for a ligne is 2.2558291 mm (1 mm = 0.443296 ligne)

15 jewl refers to the number of jewels in the watch movement.  The more jewels in the movement, the more accurate the watch is (all other things being equal) and  less friction and wear to the movement than would be caused by metal on metal.
2 adj means two adjustments.  That means that this watch was timed, or checked for accuracy, in two different positions.  For example, with the dial-up and a dial down.  It is actually possible for watch to keep good time when the dial is up and to lose accuracy if the dial is down if the watch is not checked for accuracy in both positions..  The watch accuracy can change because of the gravitational force of the earth.  Do you remember how you felt when you would do a headstand?  Gravity was affecting you differently than when you stand on your feet.  Same thing for a watch.

Next is the name of the watch company.

A 15 Jewel movement is able to keep relatively good time, even by today's standards.  Certainly not as accurate as a quartz watch but still good enough for daily use.