This full-keyboard, non-printing electric pinwheel calculating machine has nine columns of plastic keys, colored according to the place value of digits entered. At the base of each bank of keys is a ...
This full-keyboard direct multiplication non-printing electric calculating machine has an iron and steel case painted black, The nine columns of plastic black and white keys are colored according to ...
Grant’s difference engine was invented in 1876 by George Grant. It was a calculating machine and was invented as a way to advance the current calculating machine technology. It used the latest design ...
Some results have been hidden because they may be inaccessible to you
Show inaccessible results