English gold precision watch with tourbillon Circa 1912

Gold open faced lever tourbillon
–
An important and very fine precision pocket watch with tourbillon, circa 1912.
18k gold case, tiered, polished, case maker’s punch mark “FT” (Frederick Thoms), turnable pendant, glazed movement. Enamel dial, off-white, radial Roman numerals, auxiliary seconds, 30h power reserve indicator, blued spade hands. 3/4 plate movement, frosted, gilt, chatoned, signed, finely polished steel tourbillon cage, optionally keywinding or crownwinding, chain/fusee, lever escapement, gold screw compensation balance.
–
Diameter: 55 mm
–
Weight: 151 g
–
Signed: S. Smith & Son Ltd. London