细节
A 19th-century boxwood excise slide rule,
unsigned, with three sliders 12in. (30.5cm.) long; and a boxwood and ivory slide rule stamped Dollond London, 12 in. (30.5cm.) long (2)
unsigned, with three sliders 12in. (30.5cm.) long; and a boxwood and ivory slide rule stamped Dollond London, 12 in. (30.5cm.) long (2)