Invented by Leonardo Torres in 1920, the Torres calculating machine is a machine that solves essential addition, subtraction, multiplication, and division problems using a simple manner. It was a ...
This manually operated, non-printing stepped drum calculating machine has a brass mechanism on an iron support, both painted black. The machine is mounted on a slab of wood and has a rough wooden ...
Some results have been hidden because they may be inaccessible to you
Show inaccessible results