The mechanical calculator (7 h 50 m, 18 nov 2018 año – 20 h 53 m, 30 jul 2019 año)
Descripción:
The mechanical calculator then invented by Thomas de Colmar in the mid-nineteenth century, and subsequent others. It was called the Arithmometer. The concept was improved with pinwheel calculators invented by Baldwin and Odhner.
Añadido al timeline:
fecha:
7 h 50 m, 18 nov 2018 año
20 h 53 m, 30 jul 2019 año
~ 8 months