I am a litle puzzled by this watch. It measures 1.618in/41.10mm which puts it as a size 14, but I cannot find any matching plate design in the book. The case is marked A.W.Co Sterling QQ95.

Back plate

Ken,
Database says 14s

Grade: Crescent Garden
Movement Serial Number:877171
Estimated Production Year: 1875
Run Quantity: 40
Size: 14s
Jewels: 15j
Movement Configuration: Openface
Model: 1870-14
Movement Setting: Key
Plate: 3/4 Plate
Adjusted: Yes

Interesting movement.Find a full moon hour hand,and clean it, and It will look like new.
Hope this helps.

Steve

Steve, thanks for such a quick and thorough reply. What database are you referencing?

Ken,
pocketwatchdatabase.com

Lots of info there, not always correct.

Steve

According to the American (Waltham) Watch Co. Hand-Written records, these 40 movements were made December 1875-January 1876.