Details
A multiple-scale flat slide-rule
with fifteen boxwood scales on multi-ply base and eight-scale slide signed on the reverse Designed by Major General Hannyngton Aston Mander & Co. Makers London, in mahogany case with typed instructions for percentages, division and multiplication -- 33 in. (84 cm.) overall
with fifteen boxwood scales on multi-ply base and eight-scale slide signed on the reverse Designed by Major General Hannyngton Aston Mander & Co. Makers London, in mahogany case with typed instructions for percentages, division and multiplication -- 33 in. (84 cm.) overall