AddersNotched Band Adders
Building on ideas of Perrault and de Caze, in 1842 the Russian E. Kummer replaced the wooden rods on an adder with metal bands notched on each side. Kummer’s idea was adopted by the Frenchman Troncet, who published what he called an Arithmographe in the 1890s. Adders with notched bands became the most common form of the instrument sold in the United States in the 20th century.
These stylus-operated instruments generally had a crook at the top of each column, to allow one to move adjacent bands in carrying (or, in some cases, borrowing) a digit. They were manufactured around the world. Occasionally, notched band adders were combined with a slide rule, to ease multiplication and division. A special form of the instrument, designed for computer programmers, aided calculations in base 60 rather than usual decimal arithmetic.
"Adders - Notched Band Adders" showing 1 items.
- Louis-J. Troncet patented this instrument in his native France in 1889, and it was published by Larousse. The American scientist Daniel Draper purchased this example in 1895 for $2.50. It came in a small notebook with a set of multiplication tables.
- The Troncet arithmographe, like an instrument issued by the Russian E. Kummer in the 1840s, used flat metal bands with notched edges to represent digits. These bands were moved with the stylus to enter numbers. The instrument has seven crook-shaped columns that reveal the edges of eight notched bands. The crook at the top of each groove is designed to ease carrying or borrowing.
- Eight holes below the columns, labeled “ADDITION”, show the results of addition problems. Eight holes above the columns, labeled “SOUSTRACTION,” show the results of subtraction problems. There is no zeroing mechanism. Troncet’s design was widely adopted by later manufacturers.
- References: Mareschal, G., “Calculateur mecanique instante,” La Nature, 18 annee, 1890, pp. 307-308.
- P. Kidwell, “Scientists and Calculating Machines,” Annals of the History of Computing, 12 (1990): 31-40.
- P. Kidwell, "Adders Made and Used in the United States," Rittenhouse, 1994, 8:78-96.
- Currently not on view
- date made
- Librairie Larousse
- ID Number
- catalog number
- accession number
- Data Source
- National Museum of American History, Kenneth E. Behring Center