A 19th-century brass and steel pocket drawing-set, unsigned, with ebony parallel-rule, boxwood sector and bone scale rule with brass protractor in fishskin covered case 7in. (17.8cm.) long

细节
A 19th-century brass and steel pocket drawing-set, unsigned, with ebony parallel-rule, boxwood sector and bone scale rule with brass protractor in fishskin covered case 7in. (17.8cm.) long