Curta

The Curta is a small hand held mechanical calculator, shaped like a cylinder that fits in the palm of the hand and nicknamed the pepper grinder for its shape, designed by the Austrian engineer Curt Herzstark. Herzstark conceived it in Vienna during the 1930s and filed a key patent by 1938 for a single stepped drum mechanism that let the device subtract as well as add; his work was interrupted when Nazi authorities redirected his company to military production and he was imprisoned at the Buchenwald concentration camp in 1943, where he nonetheless worked out drawings for a manufacturable design. After his 1945 liberation he brought the calculator into production through Contina AG in Liechtenstein; the Type I model, introduced in 1948, gave eleven digit precision in a device weighing about 230 grams, and roughly 140,000 Curtas were made before production ended in 1972, making it the leading portable calculator of its era before electronic calculators replaced it.