細節
H. BELL, Prescot
A brass-cased folding guinea balance, with fold-over weight and sliding weight, the beam divided 0-3-6-9-12 with five notches, with instruction label in lid -- 5¼in.(13.5cm.)long, circa 1790
A brass-cased folding guinea balance, with fold-over weight and sliding weight, the beam divided 0-3-6-9-12 with five notches, with instruction label in lid -- 5¼in.(13.5cm.)long, circa 1790