Rare Swiss torpedo boat chronometer of the US Navy Circa 1905

Silver open faced lever pocket watch 
–
A rare and fine Swiss silver open faced U.S. Navy torpedo boat chronometer from the first series with 50 hour power reserve made by Longines Watch Co, circa 1905.
The case has a military engraving on the back. It also features a gold crown and hinge. The dial is silvered and has Arabic hour numerals, an outer minute track, auxiliary seconds display at 6 o’clock, a power reserve indicator at 12 and blued spade hands. The gilt bridge movement has 21 jewels, eight adjustments, screwed gold chatons,
a gold screw Guillaume compensation balance, blued balance spring according to Phillips, an index spring fine adjusting device and a counterpoised lever escapement.
–
Diameter: 67 mm
–
Weight: 250 g
–
Signed: Longines