Description
Calculating machine
A calculating machine could be any machine that adds, subtracts, multiplies or divides. Before about 1820, they were solely produced as marvels and were not sufficiently developed to be of practical use. Direct multiplication was only possible in 1895, and had immediate time-saving application, particularly in the work of insurers and astronomers.

Numbers were represented digitally, with various different methods of entry. Earlier examples usually used rotating wheels with pins protruding. The pins were linked to a weight which fell and registered the number. Later examples were key driven.

18/10/2002
Created by: Saffron Clackson on 18/10/2002