> In 1902, the Dalton went on to become one of the most popular 10-key adding machines of the time, rendering multi-column calculators obsolete.
Multi-column calculators survived much longer, being king of the hill for high-accuracy multiplication and division. I had a job using one until the end of 1969.
Multi-column calculators survived much longer, being king of the hill for high-accuracy multiplication and division. I had a job using one until the end of 1969.