Adders - Adders Using Rods
From antiquity, mathematicians have known that one can represent numbers by lengths. To find the sum of two numbers, one can use two rulers that slide next to one another, assuming the rulers are long enough. In 1700, the Frenchman Claude Perrault suggested that one could represent each digit in numbers to be summed by a separate sliding stick. Another Frenchman, C. de Caze, actually built such an instrument.
The Smithsonian collections include several models of adders submitted to the United States Patent Office. Some of these represented numbers by the length of movable rods. Another rod-type adder, invented by Clarence E. Locke of Kensett, Iowa, was the first American-made adder to sell successfully for several years.
"Adders - Adders Using Rods" showing 4 items.
Locke Adder
- Description
- The first American-made adder to enjoy modest commercial success was developed by Clarence E. Locke (1865-1945). A native of Edgerton, Wisconsin, he graduated from Cornell College in Mt. Vernon, Iowa in 1892. Locke worked for a time as a civil engineer in Minnesota, and then joined his father operating a lumberyard in Kensett, Iowa.
- This version of the device has a metal base with grooves for nine sliding metal rods that move crosswise. Each rod represents a digit of a number being added. Protruding knobs on the rods represent different numerals. The rods are held in place by metal covers, painted black, that extend over the right and left thirds of the instrument. When the device is in zero position, all the rods are in their rightmost position. Numbers are entered by sliding rods to the left, and the result appears in numbers immediately to the left of the cover on the right. The rods are color-coded to distinguish units of money. They lock when depressed, so that they will not slide if the instrument is tilted.
- The locking mechanism, the color-coded rods, and the oval shape of the knobs on the rods are all improvements featured in Locke’s second calculating machine patent, taken out in 1905. This patent is not listed on the instrument. There is no carry mechanism. The instrument sits in a wooden box with no lid. The base of it is covered with red cloth.
- The instrument is marked on the right cover: C.E. LOCKE (/) MFG. Co. It is also marked: KENSETT, IOWA. [/] U.S.A. It is marked on the left cover: THE (/) LOCKE (/) ADDER. It is also marked: PATENTED DEC. 24. 1901. This example came to the Smithsonian from the collection of Felt & Tarrant Manufacturing Company (later Victor Comptometer Corporation).
- References: C. E. Locke, “Calculating Machine,” U.S. Patent 689680, December 24, 1901.
- C. E. Locke, “Calculating Machine,” U.S. Patent 779088, January 3, 1905.
- Robert Otnes, “Sliding Bar Calculators,” ETCetera #11 (June 1990): pp. 6-8.
- P. Kidwell, “Adders Made and Used in the United States,” Rittenhouse, 8, (1994): pp. 78-96.
- Location
- Currently not on view
- date made
- 1901
- maker
- C. E. Locke Manufacturing Company
- ID Number
- MA*323619
- catalog number
- 323619
- accession number
- 250163
- Data Source
- National Museum of American History, Kenneth E. Behring Center
Locke Adder
- Description
- The first American-made adder to enjoy modest commercial success was developed by Clarence E. Locke (1865-1945), a native of Edgerton, Wisconsin, who graduated from Cornell College in Mt. Vernon, Iowa, in 1892. Locke worked for a time as a civil engineer in Minnesota, and then joined his father in operating a lumberyard in Kensett, Iowa.
- This early version of the device has a wooden base with grooves for nine sliding metal rods that move crosswise. Each rod represents a digit of a number being added. Protruding knobs on the rods represent different numerals. The rods are held in place by a metal cover that extends over about a third of the right top, and by a metal bracket on the left side. When the device is in zero position, all the rods are in their rightmost position. Numbers are entered by sliding rods to the left, and the result appears in numbers immediately to the left of the metal cover. There is no carry mechanism. The cover is brown, not black or silver-colored as in later Locke adders.
- The instrument is marked on the cover: C.E. LOCKE (/) MFG. Co. It is also marked: KENSETT, IOWA. [/] U.S.A. This example came to the Smithsonian from the collection of Felt & Tarrant Manufacturing Company (later Victor Comptometer Corporation).
- References: Robert Otnes, “Sliding Bar Calculators,” ETCetera #11 (June 1990): pp. 6-8.
- P. Kidwell, “Adders made and Used in the United States,” Rittenhouse, 8, (1994): pp. 78-96.
- Location
- Currently not on view
- date made
- 1901
- maker
- C. E. Locke Manufacturing Company
- ID Number
- MA*323620
- catalog number
- 323620
- accession number
- 250163
- Data Source
- National Museum of American History, Kenneth E. Behring Center
Locke Adder
- Description
- The first American-made adder to enjoy modest commercial success was developed by Clarence E. Locke (1865-1945). A native of Edgerton, Wisconsin, he graduated from Cornell College in Mt. Vernon, Iowa, in 1892. Locke worked for a time as a civil engineer in Minnesota, and then joined his father operating a lumber yard in Kensett, Iowa.
- This version of the device has a metal base with grooves for nine sliding metal rods that move crosswise. Each rod represents a digit of a number being added. Protruding knobs on the rods represent different numerals. The rods are held in place by bronze-colored metal covers that extend over the right and left thirds of the instrument. When the device is in zero position, all the rods are in their rightmost position.
- Numbers are entered by sliding rods to the left, and the result appears in numbers immediately to the left of the cover on the right. The rods are color-coded to distinguish units of money. They lock when depressed, so that they will not slide if the instrument is tilted. The locking mechanism, the color-coded rods, and the oval shape of the knobs on the rods are all improvements featured in Locke’s second calculating machine patent, taken out in 1905. There is no carry mechanism. The base of is covered with green cloth.
- The instrument is marked on the right cover: C. E. LOCKE (/) MFG. Co. It also is marked: KENSETT, IOWA. [/] U.S.A. It is marked on the left cover: THE (/) LOCKE (/) ADDER. It also is marked: PATENTED DEC. 24. 1901 (/) JAN. 3 1905. This example came to the Smithsonian from the collection of L. Leland Locke.
- The instrument resembles MA*323619, but it has green rather than red cloth on the bottom and has no surrounding wooden box. Also compare to MA*321327.
- References: C. E. Locke, “Calculating Machine,” U.S. Patent 689680, December 24, 1901.
- C. E. Locke, “Calculating Machine,” U.S. Patent 779088, January 3, 1905.
- Robert Otnes, “Sliding Bar Calculators,” ETCetera #11 (June 1990): pp. 6-8.
- P. Kidwell, “Adders Made and Used in the United States,” Rittenhouse, 8, (1994): pp. 78-96.
- Location
- Currently not on view
- date made
- 1905
- maker
- C. E. Locke Manufacturing Company
- ID Number
- MA*155183.29
- catalog number
- 155183.29
- accession number
- 155183
- Data Source
- National Museum of American History, Kenneth E. Behring Center
Locke Adder
- Description
- The first American-made adder to enjoy modest commercial success was developed by Clarence E. Locke (1865-1945). A native of Edgerton, Wisconsin, he graduated from Cornell College in Mt. Vernon, Iowa, in 1892. Locke worked for a time as a civil engineer in Minnesota, and then joined his father operating a lumberyard in Kensett, Iowa.
- This version of the device has a metal base with grooves for nine sliding metal rods that move crosswise. Each rod represents a digit of a number being added. Protruding knobs on the rods represent different numerals. The rods are held in place by bronze-colored metal covers that extend over the right and left thirds of the instrument. When the device is in zero position, all the rods are in their rightmost position.
- Numbers are entered by sliding rods to the left, and the result appears in numbers immediately to the left of the cover on the right. The rods are color-coded to distinguish units of money. They lock when depressed, so that they will not slide if the instrument is tilted. The locking mechanism, the color-coded rods, and the oval shape of the knobs on the rods are all improvements featured in Locke’s second calculating machine patent, taken out in 1905. There is no carry mechanism. The base of it is covered with green cloth.
- The instrument is marked on the right cover: C.E. LOCKE (/) MFG. Co. It is also marked: KENSETT, IOWA. [/] U.S.A. It is marked on the left cover: THE (/) LOCKE (/) ADDER. It is also marked: PATENTED DEC. 24. 1901 (/) JAN. 3 1905. The instrument fits in a cardboard case covered with black cloth.
- According to the donor, the example of the Locke adder was given to him by the retiring operator of a country milk receiving station for a dairy. The operator used it to determine the total number of pounds of milk received each day at the station.
- References: C. E. Locke, “Calculating Machine,” U.S. Patent 689680, December 24, 1901.
- C. E. Locke, “Calculating Machine,” U.S. Patent 779088, January 3, 1905.
- Robert Otnes, “Sliding Bar Calculators,” ETCetera #11 (June 1990): pp. 6-8.
- P. Kidwell, “Adders made and Used in the United States,” Rittenhouse, 8, (1994): pp. 78-96.
- Accession file, for advertising brochure and history of the instrument.
- Location
- Currently not on view
- date made
- 1905
- maker
- C. E. Locke Manufacturing Company
- ID Number
- MA*321327
- catalog number
- 321327
- accession number
- 243137
- Data Source
- National Museum of American History, Kenneth E. Behring Center