C. 1916 Hampden Aviator 19 Jewels

As a Christmas present to myself, I picked up this 19 jewel adjusted Hampden Aviator featuring cupids on a metallic silver face. It is estimated to be from 1916.

It needs cleaned but runs well. Sadly, most places want 300 dollars to clean it professionally!

A fully-jeweled watch is 17 jewels, so this is a cut above. The jewels are points of the highest wear. They happen to be more durable than metal, so a jeweled watch will last longer (generally) than an unjeweled (or less-jeweled) watch and will keep better time as it doesn't wear out.
Adjustments are typically: normal temperature changes won't affect it, and it can be in multiple positions and still keep accurate time. If it's unadjusted, it is a lower quality watch.

The watch it just beautiful, and I stalked the e-Bay auction and pounced at the last minute (15 seconds, actually) to make it mine.

As a few more notes, I believe the crystal has been replaced as it is undamaged-- odd, for a century-old open-face pocket watch.
It's a stem set and wind.
Supposed to be gold-plate, but looks like it used to be silver with gold edge-work to me.