31. The arithmometer was the first mechanical calculator strong enough and reliable enough to be used daily in an office environment. 32. :: : I remember a mechanical calculator from the 1960s that would run indefintiely if you divided by zero. 33. In the 1930s, the rest of the nascent computing industry was limited to mechanical calculators that used the decimal system. 34. By the early 1970s electronic pocket calculators ended manufacture of mechanical calculators , although the Curta remains a popular collectable item. 35. In the 1940s and 1950s, using mechanical calculators , women in an all-female computations group performed trajectory calculations. 36. For 40 years, the arithmometer was the only mechanical calculator available for sale and was sold all over the world. 37. It was at Trinity College here that Charles Babbage, inventor of the mechanical calculator , studied mathematics in the early 1800s. 38. Handheld mechanical calculators such as the 1948 Curta continued to be used until they were displaced by electronic calculators in the 1970s. 39. Under the popular leadership of Gunnar Ericsson, Facit focused increasingly on its mechanical calculators , branding, marketing and global expansion. 40. Any other mechanical calculator capable of fully automatic analog comparators to anticipate the overdraft, and prepare for the next quotient digit.
