Calculating Machines II

Reckoning with Rods and Pinwheels

In the early seventeenth century, the Scotsman John Napier invented his reckoning rods for doing multiplication. Within only a few years, Napier's rods were all the rage in Europe. Together, we shall learn how easily and quickly we can multiply large numbers with these rods.

In the eighteenth century the first mechanical calculating machines appeared, with which one could perform all four operations of arithmetic. One type uses a so-called pinwheel for representing numbers mechanically, and together we shall use original Schubert pinwheel-machines from 1969 to do arithmetic.