Calcumeter

In 1901 James J. Walsh from Elizabeth, New Jersey, was granted a US patent No 689255 for an adding machine, type dial adder, which will became popular later as Calcumeter. This stylus-driven cogged wheel adder was manufactured from 1901 by the company Morse & Walsh Co., Trenton NJ, with remarkable market success.

The patent drawing of Walsh

There are variants of the machine with 5 to 12 dials. A 5-dial machine was $10. Each additional dial cost $5, so the 12-dial machine was $45. In 1907 are manufactured 35 models. According to the advertisement in 1913 the machine has 100000 users. At some point, a reset dial was added (patented again by Walsh, US patent No 897688 from 1908), and the machine was sold as the Standard Desk Calcumeter.

The Calcumeter of Walsh

An interesting feature of Calcumeter is so called stored-energy carry, which is not common on small adders. The stored-energy carry in a sense winds a spring as a given dial is turned. When the dial is turned to position 9, the spring is fully compressed. When the dial is turned one more position to 0, then the spring is released causing it to add one to the position to the left. With a long carry, the carries will ripple across to the left one after another without a great deal of effort on the part of the user other than inputting the single unit on one dial.