Stepped Drum Calculating Machines

An image featuring several calculating machines from the collection.

The distinguished mathematician and philosopher Gottfried William Leibniz started thinking about stepped drum calculating machines in the 1670s, and an eighteenth century instrument built on his design survives. However, it was the French insurance executive Charles Xavier Thomas (1785-1870) who invented and sold the first commercially successful calculating machine. Proposed in 1820, it would sell successfully from about 1850.

Thomas’s calculating machine, which he dubbed the arithmometer, had cylindrical brass drums, each with nine teeth that varied in length.  If a setting lever was at “9”, it engaged nine teeth, at 8, eight teeth and so forth. This stepped drum mechanism would be modified over time, with different metals used for the stepped drums, much of the drum cut away, and different arrangement of the teeth on the gears. Nonetheless, the stepped drum survived as part of some calculating machines as long as they were manufactured.

Friden Model C 10 Calculating Machine

The Swedish-born inventor Carl Friden was stranded in Australia during World War I and then, on his way back to Sweden, decided to settle in California. He found a place at the Marchant Calculating Machine Company, taking out several patents for machines manufactured there.
Description
The Swedish-born inventor Carl Friden was stranded in Australia during World War I and then, on his way back to Sweden, decided to settle in California. He found a place at the Marchant Calculating Machine Company, taking out several patents for machines manufactured there. By 1933, he had decided to start his own company. The Friden models A and B appeared in 1934. In 1936 the young company introduced this machine, the model C. It was sold in two sizes, one which allowed entry of numbers up to eight digits long (the C 8) and one allowing ten-digit entries (the C 10). This is a later version of the model C 10, introduced in about 1941.
The full-keyboard, electric non-printing stepped drum calculating machine has a metal frame painted gray-brown. The ten columns of color-coded light green and blue-green plastic number keys have a blank green clearance key at the bottom of each column. Metal rods between the columns of keys turn to indicate decimal places. On the right are function keys, including a RETURN (/) CLEAR key. This key is not found on the earlier model C10, such as object 1982.243.01. The machine has no special keys for multiplication.
Behind the number keys is a movable carriage with an 11-digit revolution register and a 21-digit result register. The result register has green plastic buttons above it that rotate to set up numbers. Under the revolution register are further numbered buttons. Zeroing knobs for the registers are on the right of the carriage. Decimal markers slide between the registers on the carriage. The result register also has a sliding marker to cover over a digit. A cord comes out of the back of the machine (it is not a separate part). The machine has strips of metal around the corners, as on later Friden calculating machines.
A mark on the bottom reads: C10-53041. A mark on the sides reads: FRIDEN. A metal tag attached to the right side reads: U.S.NAVY BU.ORDNANCE (/) CONTRACT N ORD. (F) 1236 (/) SY.-SER.NO. (/) IV E B K. A mark painted on right side reads: C810 (/) USN. A paper sticker attached to right side reads: APL/JHU (/) Controller (/) Group (/) 1975 (/) INVENTORY
Compare 1982.0243.01.
The mark on this machine indicates that it, along with MA.335427, was used at the Applied Physics Laboratory of Johns Hopkins University.
The donor dated this machine to 1946 and said that the initial price was $405. The date 1944 is from Jorgenson
References:
E. Jorgenson, Friden Age List, Office Machine Americana, p. 2.
Accession File.
Location
Currently not on view
date made
ca 1944
maker
Friden Calculating Machine Company
ID Number
MA.335422
catalog number
335422
accession number
319049
maker number
C10 53041

Friden Model C 10 Calculating Machine

The Swedish-born inventor Carl Friden was stranded in Australia during World War I and then, on his way back to Sweden, decided to settle in California. He found a place at the Marchant Calculating Machine Company, taking out several patents for machines manufactured there.
Description
The Swedish-born inventor Carl Friden was stranded in Australia during World War I and then, on his way back to Sweden, decided to settle in California. He found a place at the Marchant Calculating Machine Company, taking out several patents for machines manufactured there. By 1933 he had decided to start his own company. The Friden models A (8-digit entries) and B (10-digit entries) appeared in 1934.
In 1936 the young company introduced this machine, the model C. It featured automatic return clearance for the carriage and dials and was sold in two sizes, one that allowed entry of numbers up to eight digits long (the C 8) and one allowing ten-digit entries (the C 10). This is an early example of the C 10. It has a case painted greenish black. A later version of the model C, introduced in about 1941, had a gray case. It sold until 1949.
The stepped drum, full-keyboard electric non-printing calculating machine has ten columns of black and white plastic number keys, colored to make it easy to distinguish different units of money. A blank clearance key of red plastic is at the bottom of each column. Metal rods between the columns of keys turn to indicate decimal places. On the right are red and black function keys. The machine has no separate keys for multiplication.
Behind the number keys is a movable carriage with an 11-digit revolution register and a 21-digit result register. An arrow above the first column of keys assists in setting the carriage. The result register has plastic buttons above it that can be used to set up numbers. Decimal markers slide above the two registers. Zeroing knobs are on the right of the carriage. The cord is missing. The corners of the machine have metal streamlines. It resembles in key color and general appearance the contemporary Marchant keyboard electric machines built on Friden’s patent.
The machine is marked on the sides: FRIDEN. A second mark, visible through a window at the front of the machine, is: C10-41272. A paper tag glued to the front left of the machine reads: FRIDEN CALCULATIN [...] ACHINE CO. (/) OAKLAND, CALIF. The Friden Calculating Machine Company moved from Oakland to San Leandro in 1936.
Compare the Marchant ERB calculating machine with museum number 1977.1225.01, as well as a later model C 10 with catalog number MA.335422.
This machine was transferred to the collections from the Office of Exhibits at the Smithsonian’s National Museum of Natural History in 1982. It had no Smithsonian Institution tag.
References:
Carl Holm, “Milestones in the Development of Friden.”
Ernie Jorgenson, Friden Age List, Office Machine Americana, p. 1
Location
Currently not on view
date made
1936
maker
Friden Calculating Machine Company
ID Number
1982.0243.01
catalog number
1982.0243.01
accession number
1982.0243
maker number
C10 41272

Friden Model S 10 Calculating Machine

By 1939 Friden Calculating Machine Company had introduced a “Supermatic” version of its calculating machine that featured multiplication by direct entry of digits (rather than repeated addition).
Description
By 1939 Friden Calculating Machine Company had introduced a “Supermatic” version of its calculating machine that featured multiplication by direct entry of digits (rather than repeated addition). This is an example of that full-keyboard non-printing electric stepped drum machine. It has a metal frame painted gray and ten columns of color-coded gray and blue-green plastic number keys, with a blank green key at the bottom of each column.
Metal rods between the columns of keys turn to indicate decimal places. On the right are two columns of function bars and keys. On the left is a register that indicates numbers entered for multiplication. Below it is a block of 9 white digit keys, with a 0 bar below. These are surrounded by further levers and function keys.
Behind the number keys is a movable carriage with an 11-digit register and a 21-digit result register. The result register has plastic buttons above it that can be used to set up numbers. Zeroing knobs for the registers are on the right of the carriage. Decimal markers slide below the two registers on the carriage. The machine has four hard rubber feet. An electric cord attachs to the machine at the back.
A mark on the bottom of the machine reads: S10-105632. A mark on the back and sides reads: FRIDEN. A sticker attached to the bottom reads: MODEL S. It also reads: FRIDEN CALCULATING MACHINE CO., INC. [() MADE IN SAN LEANDRO, CALIFORNIA, U.S.A. It also reads: DESIGN PAT. 103,425.
Design patent D103,425 was granted to Carl M. Friden March 2, 1937. According to Carl Holm of Neopost, the model S 10 was introduced in 1938. The date given is from Jorgenson.
Reference:
Ernie Jorgenson, Friden Age List, Office Machine Americana, p. 2.
Location
Currently not on view
date made
1939
maker
Friden Calculating Machine Company, Inc.
ID Number
MA.334378
catalog number
334378
accession number
313935
maker number
S10 105632

Monroe Model LA5-160 Calculating Machine

This compact full-keyboard electric non-printing and modified stepped drum calculating machine has a steel frame with rounded corners painted mottled dark green. The steel plate under the keyboard is painted light green.
Description
This compact full-keyboard electric non-printing and modified stepped drum calculating machine has a steel frame with rounded corners painted mottled dark green. The steel plate under the keyboard is painted light green. The eight columns of white plastic keys have nine keys in each column. Between the columns of keys, and under the green plate, are metal rods visible through windows in the plate. These serve as decimal markers.
To the right of the number keys are the subtraction and addition bars, two red buttons, one of which is marked R, and a red clearance key. Left of the keyboard is a lever with a red plastic top. In back of the keyboard is the carriage, with 16 result dials and eight revolution register dials. A crank with a wooden handle for clearing the carriage is on its right side and another one for shifting the carriage at the front. The machine has four rubber feet. A gray rubber electric cord plugs into the back, and a light gray cover fits over the object.
A mark on the front of the machine and on the cord reads: MONROE. A mark on the back reads: MONROE (/) REGISTERED TRADE MARK (/) HIGH SPEED ADDING CALCULATOR. The serial number, scratched on the underside of the carriage on the left, is 250245. The cover is marked: MONROE li.
This machine was used to keep the financial records of the Friends Meeting of Washington. Date deduced from serial number.
Compare MA.335424 and MA.334385.
References:
Accession file.
National Office Machine Dealer’s Association, Blue Book, May, 1975, as compiled by Office Machine Americana, January, 2002.
Location
Currently not on view
date made
1940
maker
Monroe Calculating Machine Company
ID Number
MA.335235
catalog number
335235
accession number
314611

Monroe Calculating Machine (Model K-16?)

This full-keyboard manually operated, non-printing, modified stepped drum calculating machine has a crinkled metal exterior with rounded corners, painted light green. The green paint has worn away in some places to reveal black paint beneath.
Description
This full-keyboard manually operated, non-printing, modified stepped drum calculating machine has a crinkled metal exterior with rounded corners, painted light green. The green paint has worn away in some places to reveal black paint beneath. The steel plate underneath the keys is dark green.
The machine has eight columns of black and white plastic digit keys. Rods between the columns of keys that serve as decimal markers. They are painted white on one side and the same green as the plate under the keyboard on the other. Pushing a red key at the bottom of each column zeros that column of keys. The key stems are of uniform length. A metal lever is to the right of the keyboard and a metal knob to the left. Rotating a crank on the right side clockwise adds numbers entered, moving it counterclockwise subtracts.
The carriage behind the keyboard has a row of 16 numeral dials for recording results. Eight numeral dials in a row behind these serve as a revolution register. Two thin metal rods between the windows carry decimal markers. The crank for shifting the carriage is at the front of the machine. A knob for lifting the carriage is to the right of the result register, and a crank for zeroing dials is on the right side of the carriage. The machine has four rubber feet. To the left of the keyboard is a metal knob with an arrow on it. This knob is painted green.
A mark on the front and back sides reads, in cursive writing, Monroe. The mechanism of the machine, inside the carriage on the right, has the serial number: K66367
Compare MA.334711, MA.307386, 1983.0831.01, and 1982.0682.05.
The date of this machine is a mystery. The model resembles the K-16 described in McCarthy’s 1924 American Digest of Business Machines. The serial number is one the NOMDA blue book would associate with 1926. However, the Monroe logo is of a form introduced in 1940, and the light green color is quite unlike other Monroe machines of the 1920s.
The machine was given to the Smithsonian by David G. Owen, a statistician in the Research Division of the Miami Heart Institute.
References:
National Office Machine Dealer’s Association, Blue Book, May 1975, as compiled by Office Machine Americana, January, 2002.
U.S. Patent and Trademark Office, Trademark Registration #522928, Serial #71117235.
Accession file.
Location
Currently not on view
date made
1940s
maker
Monroe Calculating Machine Company
ID Number
MA.334711
catalog number
334711
maker number
A66367
accession number
311324

Friden Model ST 10 Calculating Machine

Friden Calculating Machine Company produced its “Supermatic Tabulating” model from about 1940 through 1949.
Description
Friden Calculating Machine Company produced its “Supermatic Tabulating” model from about 1940 through 1949. This full-keyboard, non-printing electric stepped drum calculating machine has a metal frame painted gray and ten columns of light green and blue-green plastic number keys. A blank green plastic zeroing key is at the bottom of each column. Metal rods between the columns of keys turn to indicate decimal places. On the right are two columns of function keys.
On the left is a ten-digit register that indicates numbers entered for multiplication. Below it is a block of nine light green digit keys, with a 0 bar below. These are surrounded by four function keys.
Behind the number keys is a movable carriage with an 11-digit revolution register and a 21-digit result register. The result register has dark green plastic buttons above it that rotate to set up numbers. Ten numbered buttons are under the revolution register, spaced between the digits. Zeroing knobs for these registers are on the top right of the carriage. Decimal markers slide on bars between the two registers on the carriage.
A mark on the sides and back of the machine reads: FRIDEN. A paper tag on the bottom of the machine, which also includes address and patent numbers, reads: MODEL-ST. A window at the front of the bottom shows the serial number: ST10-157950.
The machine has a rubber-covered cord
The date was given by the donor, who said that the initial price was $550.
Compare 1984.3079.01, 1984.3079.02, 1984.3079.03, and MA.335427.
References:
Accession File.
Date also given in Ernie Jorgenson, Friden Age List, Office Machine Americana, p. 2.
Location
Currently not on view
date made
1945
maker
Friden Calculating Machine Company
ID Number
MA.335421
catalog number
335421
accession number
319049
maker number
ST 10 157950

Friden Model D 8 Calculating Machine

Although the United States government had made use of computing devices at least from the 1850s, World War II brought unprecedented demands for calculations. These were met, in part, by large groups of people called computers, who used desk calculators like this one.
Description
Although the United States government had made use of computing devices at least from the 1850s, World War II brought unprecedented demands for calculations. These were met, in part, by large groups of people called computers, who used desk calculators like this one. This particular machine was used at the Applied Physics Laboratory operated by Johns Hopkins University. When human computers were overwhelmed by the quantity of work that needed doing, new kinds of machines were invented .
This stepped drum machine has a metal frame painted gray, and eight columns of light green and blue-green plastic number keys, with a blank key of green plastic at the bottom of each column. These keys allow one to enter numbers of up to eight digits. Metal rods between the columns of keys turn to indicate decimal places.
On the right are two columns of function keys. The machine has no separate keys for multiplication. It has a key for cross tabulation.
Behind the number keys is a movable carriage with an nine-digit revolution register and a 17-digit result register. An arrow above the first column of keys assists in setting the carriage. Plastic buttons above the result register can be used to set up numbers. The carriage has sliding decimal markers for the two registers, as well as zeroing knobs on the right.
Marks on the sides and back of the machine read: FRIDEN. A mark visible through windows at the bottom front reads: D8-215775. A paper tag glued to the bottom reads: MODEL-D (/) FRIDEN CALCULATING MACHINE CO. INC. (/) MADE IN SAN LEANDRO, CALIFORNIA, U.S.A. (/) MANUFACTURED UNDER ONE OR MORE OF THE FOLLOWING U.S. PAT’S (/) DES. 103,425 2,229,889 2,229,890 2,229,895 2,229,901. A mark painted on the back reads: APL (/) 9601 (/) USN
References:
Ernie Jorgenson, Friden Age List, Office Machine Americana, Lewiston, Idaho p. 2.
"Carl Maurice Frederick Friden," National Cyclopaedia of American Biography, Clifton, N.J.: James T. White & Co., 54, 1973, pp. 7–8.
Location
Currently not on view
date made
1945
maker
Friden Calculating Machine Company
ID Number
MA.335427
catalog number
335427
accession number
319049
maker number
D8 215775

Friden Model FT 10 Calculating Machine

This full-keyboard electric stepped drum calculating machine is non-printing. It has a metal frame painted gray and ten columns of color-coded light-green and blue-green plastic number keys, with a blank green clearance key at the bottom of each column.
Description
This full-keyboard electric stepped drum calculating machine is non-printing. It has a metal frame painted gray and ten columns of color-coded light-green and blue-green plastic number keys, with a blank green clearance key at the bottom of each column. Metal rods between the columns of keys turn to serve as decimal markers.
On the right are two columns of function bars. To the right of these is another column of blue-green keys, with another green clearance key at the bottom. Pushing these keys allows direct multiplication by a single digit. Friden had introduced this feature in its Model F calculating machine. The model FT, of which this is an example, featured division tabulation as well. The company also sold calculating machines in which multiplication by several-digit numbers could occur automatically (see descriptions of the model S 10).
The movable carriage behind the number keys has an 11-digit multiplier register and a 20-digit result register, both with sliding decimal markers. Plastic buttons above the result register rotate to set up dividends. Ten numbered buttons are under the revolution register. Zeroing knobs for the registers are on the right of the carriage. The machine has four rubber feet.
The serial number, marked on the bottom of the machine is: FT10-79740. The side and back are marked: FRIDEN. A sticker on the bottom reads: MODEL FT. It also reads: FRIDEN CALCULATING MACHINE CO., INC. (/) MADE IN SAN LEANDRO, CALIFORNIA, U.S.A.. It has the patent numbers: 2,273,857, 2,229,901, and D-103,425.
The black plastic cover is marked: IBM.
Date from Ernie Jorgenson.
References:
C. M. F. Friden, "Calculating Machine," U.S. Patent 2,273,857, February 24, 1942.
A. I. Richards, "Calculating Machine," U.S. Patent 2,229,901, January 28, 1941.
C. M. F. Friden, "Design for a Calculating Machine with Shiftable Carriage," U.S. Design Patent D103425, March 2, 1937.
E. Jorgenson, Friden Age List, Office Machine Americana, p. 2.
Location
Currently not on view
date made
1946
maker
Friden Calculating Machine Company, Inc.
ID Number
MA.334383
catalog number
334383
accession number
313935
maker number
FT10-79740

Monroe Model LA 200 Calculating Machine

This portable, full-keyboard, electric, and non-printing modified stepped drum calculating machine has a gray steel case and gold and white color-coded plastic keys. The ten columns of keys have nine digit keys and one zeroing key in each column.
Description
This portable, full-keyboard, electric, and non-printing modified stepped drum calculating machine has a gray steel case and gold and white color-coded plastic keys. The ten columns of keys have nine digit keys and one zeroing key in each column. The zeroing key is the opposite color from the rest of the keys in the column. Between the columns of keys, and under the plate, are metal rods visible through windows in the plate. These rods, painted green on one side and red on the other, serve as decimal markers.
To the right of the number keys are two red buttons, one of which is marked R (for use in repeated addition or subtraction), and a red clearance key. A crank on the right side rotates clockwise for addition and counterclockwise for subtraction. Above these are black subtraction and addition bars.
In back of the keyboard is the carriage, with 20 result dials and ten revolution register dials. Each revolution register dial is numbered from 0 to 9 in black and from 1 to 9 in red. Between the two registers on the carriage are two thin metal rods that carry green plastic decimal markers. A crank for clearing the carriage is on its right side. A carriage shift crank is at the front.
The machine may be operated automatically by plugging in the gray rubber two-pronged cord that extends from the back. The instrument has four metal feet, a gray plastic cover, and a brown leather-covered carrying case with key.
The machine is marked on the front: Monroe. No serial number found.
For related documentation, see 1986.0131.02. Date assigned is copyright date of the instructions.
This Monroe model L calculating machine is not only electrically operated (hence the A in the model number) but has a 20-digit capacity. Although it has a carrying case (hence the X in the model number), there are no extensible feet in the back, as on the L160-X.
Reference:
Monroe Calculating Machine Company, Instruction Book Monroe Adding Calculator LA- Models, Orange, N.J., 1947 (1986.0131.02).
Location
Currently not on view
date made
1947
maker
Monroe Calculating Machine Company
ID Number
1986.0131.01
catalog number
1986.0131.01
accession number
1986.0131

Monroe Model LA5-160x Calculating Machine

This full-keyboard, non-printing electric modified stepped drum calculating machine has a metal frame painted black, with a plate under the keyboard that appears to be unpainted. The eight columns of white plastic number keys have nine keys in each column.
Description
This full-keyboard, non-printing electric modified stepped drum calculating machine has a metal frame painted black, with a plate under the keyboard that appears to be unpainted. The eight columns of white plastic number keys have nine keys in each column. Below each column is a tenth white key used for zeroing. Between the columns of keys, and under the plate, are metal rods visible through windows in the plate that serve as decimal markers. To the right of the number keys are the subtraction and addition bars, two red buttons, and a red clearance button.
In back of the keyboard is the carriage, with 16 result dials and eight revolution register dials. A carriage shift crank is at the front. The machine has four rubber feet, and a gray rubber electric cord. It has no case and the feet are not extensible at the back.
A mark on the machine reads: MONROE (/) HIGH SPEED ADDING CALCULATOR. Another mark reads; PROPERTY U.S.N.BU.ORD. (/) CONTRACT NOO 1709 (/) U.S.N. NO 504487. A mark scratched on the inside of the carriage at the left reads: 273166.
Compare MA.334385.
The donor was a certified public accountant who had a collection of calculating machines. The date of manufacture and original cost ($375) are provided by him.
References:
National Office Machine Dealer’s Association, Blue Book, May, 1975, as compiled by Office Machine Americana, January, 2002.
Monroe Calculating Machine Company, “Monroe High Speed Adding-Calculator,” Publication 780-A. This is a notebook with advertising descriptions of several Monroe calculating machines.
Accession file.
Location
Currently not on view
date made
1948
maker
Monroe Calculating Machine Company
ID Number
MA.335424
accession number
319049
maker number
273166
catalog number
335424

Monroe Calculating Machine Model L160-X

This small key-set manually operated non-printing modified step drum calculating machine has a steel case painted black with white and gold round color-coded plastic keys. The eight columns of keys have nine digit keys and one zeroing key in each column.
Description
This small key-set manually operated non-printing modified step drum calculating machine has a steel case painted black with white and gold round color-coded plastic keys. The eight columns of keys have nine digit keys and one zeroing key in each column. The zeroing key is the opposite color from the rest of the keys in the column. Between the columns of keys and under the light green plate are metal rods, visible through windows in the plate, which serve as decimal markers. These rods are painted red on one side and the same green as the plate on the other.
To the right of the number keys are two red buttons, one of which is marked R (for use in repeated addition or subtraction), and a red clearance key. A crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
In back of the keyboard is the carriage, with 16 result dials and eight revolution register dials. The revolution register dials are numbered from 0 to 9 in black and 1 to 9 in red. Between the windows of these registers are two thin metal rods that carry decimal markers. A crank for clearing the carriage is on its right side and another one for shifting the carriage at the front.
The machine has two rubber feet at the front and two collapsible metal standing pieces extending from the back at the bottom, so that it is held at an angle. The standing pieces fit up within the frame of the machine, and the entire device fits in a case covered with black leather. A black cover for the machine fits inside the case.
A mark on the front of the machine and on the cover reads: Monroe. A sticker attached to the right side of the machine reads: COUNTY BUSINESS MACHINES (/) CBM; Phone 235-9034 (/) RICHMOND. The serial number scratched on the underside of the carriage at the left, is 418947.
Compare to 1993.0396.01. Dated from serial number.
This is the “Executive Model” of Monroe’s Model L calculating machine. The “160” signifies the 16-digit result, the X the presence of the case. Manually operated machines were designated simply as “L.” Those operated electrically were “LA.”
References:
National Office Machine Dealer’s Association, Blue Book, May 1975, as compiled by Office Machine Americana, January 2002.
Monroe Calculating Machine Company, “Monroe High Speed Adding-Calculator,” Publication 780-A. This is a notebook with advertising descriptions of several Monroe calculating machines.
Location
Currently not on view
date made
1948
maker
Monroe Calculating Machine Company
ID Number
MA.336523
catalog number
336523
accession number
1978.0402

Monroe Model LA5-160 Calculating Machine

This full-keyboard electric non-printing stepped drum calculating machine has a metal frame painted black, with the plate under the keyboard painted green. The eight columns of white and tan plastic number keys have nine keys in each column.
Description
This full-keyboard electric non-printing stepped drum calculating machine has a metal frame painted black, with the plate under the keyboard painted green. The eight columns of white and tan plastic number keys have nine keys in each column. Below each column is a tenth white key used for zeroing. Between the columns of keys, and under the green plate, are metal rods visible through windows in the plate which serve as decimal markers.
To the right of the number keys are the subtraction and addition bars, a red button, and a red clearance key. Left of the keyboard is a lever. In back of the keyboard is the carriage, with 16 result dials and eight revolution register dials. The revolution register dials have the digits 1 to 9 in red and 0 to 9 in black. There is a crank for clearing the registers on the carriage on its right side and another one for shifting the carriage at the front. The machine has four rubber feet.
A mark on the front of the object reads: Monroe. A tag on the right side reads: LA5-160 (/) 472869
Compare MA.335424 and MA.335235. The Monroe LA5-160 was introduced in 1932.
References:
Business Equipment Topics, vol. 81, July, 1932, p. 14, 16.
National Office Machine Dealer’s Association, Blue Book, May, 1975, as compiled by Office Machine Americana, January, 2002.
Monroe Calculating Machine Company, “Monroe High Speed Adding-Calculator,” Publication 780-A. This is a notebook with advertising descriptions of several Monroe calculating machines.
Business Equipment Topics, vol. 81, July, 1932, p. 14, 16.
Location
Currently not on view
date made
1949
maker
Monroe Calculating Machine Company
ID Number
MA.334385
catalog number
334385
maker number
LA5-160 472869
accession number
311886

Monroe Model L160-X Calculating Machine

This lightweight modified stepped drum full-keyboard non-printing calculating machine is manually operated. It has a gray steel case and gray and white plastic keys, colored to distinguish digits of differing place value.
Description
This lightweight modified stepped drum full-keyboard non-printing calculating machine is manually operated. It has a gray steel case and gray and white plastic keys, colored to distinguish digits of differing place value. The eight columns of keys each include nine digit keys and one zeroing key. The zeroing key is the opposite color from the rest of the keys in the column. Between the columns of keys, and under the case, are metal rods visible through windows in the case. These serve as decimal markers. To the right of the number keys are two orange buttons, one of which is marked R (for use in repeated addition or subtraction), and an orange clearance key. A crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
In back of the keyboard is the carriage, with 16 result dials and eight revolution register dials. The dials of the revolution register are numbered around the edge from 9 to 0 white and from 1 to 9 in red. A crank for clearing the carriage is on its right side. The carriage shift crank is at the front. Two rubber feet are at the front and two metal standing pieces extend from the back at the bottom, holding the machine at an angle.
This model of the Monroe normally came with a carrying case, but this does not survive.
Compare MA.336523 (1978.0402.01).
References:
National Office Machine Dealer’s Association, Blue Book, May 1975, as compiled by Office Machine Americana, January, 2002.
Monroe Calculating Machine Company, “Monroe High Speed Adding-Calculator,” Publication 780-A. This is a notebook with advertising descriptions of several Monroe calculating machines.
Location
Currently not on view
date made
1953
maker
Monroe Calculating Machine Company
ID Number
1993.0396.01
catalog number
1993.0396.01
maker number
L160-X 628561
accession number
1993.0396

Friden Model STW 10 Calculating Machine

This stepped drum full-keyboard electric non-printing calculating machine has a metal frame painted brownish gray (taupe) and ten columns of brown and gray plastic number keys, with a blank gray plastic zeroing key at the bottom of each column.
Description
This stepped drum full-keyboard electric non-printing calculating machine has a metal frame painted brownish gray (taupe) and ten columns of brown and gray plastic number keys, with a blank gray plastic zeroing key at the bottom of each column. Metal rods between columns of keys turn under the keyboard to indicate decimal places. A small brown and tan bar slides to the right to reset the decimal rods. The capabilities of the Friden STW-10 are quite similar to those of the earlier ST-10, although the exterior design and color are different. The model was introduced in 1949 and manufactured through 1966.
On the right are two columns of function bars. On the left is a ten-digit register that indicates numbers entered for multiplication. Below it is a block of nine white digit keys, with a 0 bar below. These are surrounded by three levers and four function keys.
Behind the number keys is a movable carriage with an 11-digit revolution register and a 20-digit result register. Taupe plastic buttons above the result register rotate to set up numbers. Ten numbered buttons under the revolution register are spaced between the digits. A zeroing knobs for the registers is on the top right of the carriage. All three registers have sliding decimal markers.
The machine has four hard rubber feet. There is a rubber cord and a tan plastic cover. A mark on the bottom of the machine reads: S82 (/) STW 10. The original serial number next to the model number has been effaced. Marks on the back and side read: FRIDEN. A mark on the cover reads: Friden (/) AUTOMATIC CALCULATOR. A mark on a sticker on the bottom of the machine reads: FRIDEN, INC. (/) SAN LEANDRO, CALIFORNIA, U.S.A. A mark on the cord reads: SINGER.
Compare MA.334379, MA.335419 and 1984.3079.04.
Reference:
Carl Holm, “Milestones in the Development of Friden.”
Location
Currently not on view
date made
ca 1954
maker
Friden, Inc.
ID Number
MA.334379
accession number
313935
catalog number
334379
maker number
S-82

Curta Type I Calculating Machine

This compact cylindrical handheld calculating machine has black metal sides and a plastic top and operating handle. Eight slots along the side of the cylinder hold levers that are pulled down to set numbers. The digit entered appears at the top of the slot.
Description
This compact cylindrical handheld calculating machine has black metal sides and a plastic top and operating handle. Eight slots along the side of the cylinder hold levers that are pulled down to set numbers. The digit entered appears at the top of the slot. Holes around the edge of the top reveal the digits of the multiplier, which may be up to six digits large. The result also shows through holes around the edge of the top, and may be 11 digits large. The top may be rotated, as one one would move a carriage on an earlier stepped drum calculating machine. Sliding decimal markers indicate decimal places in entries, multipliers, and results.
To zero the machine, one raises the carriage and rotates a black disc under the operating lever through one turn. The operating handle is pulled out for subtraction and division. Moving a lever on the side of the cylinder causes subtraction rather than addition in the revolution counting register. The machine fits in a black metal cylindrical case. The lid of the case turns clockwise to open.
The operating instructions received with the machine are stored separately.
The machine is marked on the case and on the side: CURTA. It is marked on the base: System Curt Herzstark (/) Made in Liechtenstein (/) by Contina AG Mauren (/) Type I No 34691. It is also marked there: Scholl (/) POSTSTRASSE 3. ZURICH. It is marked on the lid: OPEN.
This example of the Curta was used by Professor Charles T. G. Looney, who taught engineering at the University of Maryland.
The Curta calculating machine was invented by the Austrian Curt Hertzstark (1902–1988). He worked on the design during World War II as a prisoner at the Nazi concentration camp of Buchenwald, and produced the machine after the war in Leichtenstein. The Curta Type I was manufactured from 1949 until early 1972, when handheld electronic calculators replaced it.
Compare to 1981.0922.01.
Reference:
Curt Hertstark, Interview with Erwin Tomash, September 10 and 11, 1987, Oral History 140, Charles Babbage Institute, Minneapolis, Minnesota.
Location
Currently not on view
date made
1957
maker
Contina AG Mauren
ID Number
MA.333848
catalog number
333848
accession number
303780
maker number
34691

Curta Type II Calculating Machine

This compact cylindrical handheld stepped drum calculating machine has gray metal sides and a black top and operating handle. Eleven slots along the side of the cylinder have plastic red and black levers that are pulled down to set numbers.
Description
This compact cylindrical handheld stepped drum calculating machine has gray metal sides and a black top and operating handle. Eleven slots along the side of the cylinder have plastic red and black levers that are pulled down to set numbers. The digit entered appears at the top of the slot. Multipliers are indicated by numbers read through holes around the edge of the top and may be up to 8 digits large. The result also is indicated around the edge of the top, and may be 15 digits large. The top rotates, as one one would move a carriage on an earlier stepped drum machine. Sliding markers indicate the position of decimals for entries, multipliers, and results.
To zero the machine, the carriage is raised and the black disc under the operating lever is rotated through one turn using a clearing lever with a ring-like handle. The operating handle is pulled up for subtraction and division. Moving a lever on the side of the cylinder causes subtraction rather than addition in the revolution counting register. The machine fits in a black metal cylindrical case.
The machine is marked on the side: CURTA. The bottom reads: Type II (/) No 515677 (/) Made in Liechtenstein (/) (Customs Union with Switzerland) (/) by Contina Ltd Mauren (/) System Curt Hertstark. The side of the case reads: CURTA (/) OPEN. It also reads: PROPERTY OF HERBERT L. WATKINS.
Compare to 1983.0471.05.
Herbert L. Watkins (1926-1986) was a land surveyor in Silver City, New Mexico.
References:
Curt Hertstark, Interview with Erwin Tomash, September 10 and 11, 1987, Oral History 140, Charles Babbage Institute, Minneapolis, Minn. Hertstark dates the beginning of production of the Curta to 1949.
Cliff Stoll, “The Curious History of the First Pocket Calculator,” Scientific American, (January 2004), pp. 82-89. The Model II reportedly was introduced in 1954, after Hertstark had left the company.
Location
Currently not on view
date made
1957
maker
Contina Ltd Mauren
ID Number
1989.3049.01
catalog number
1989.3049.01
nonaccession number
1989.3049
maker number
515677

Monroe Model CSA8 Calculating Machine

This is a very late example of a product of the Monroe Calculating Machine Company of New Jersey, made when the firm was still an independent company.The compact non-printing, full keyboard, electric modified stepped drum calculating machine has a gray steel case and eight column
Description
This is a very late example of a product of the Monroe Calculating Machine Company of New Jersey, made when the firm was still an independent company.
The compact non-printing, full keyboard, electric modified stepped drum calculating machine has a gray steel case and eight columns of gray and light gray oblong plastic color-coded number keys, with a zeroing key of the same color at the bottom of each column. Between the columns of keys, and under the light gray plate, are metal rods (visible through windows in the plate) that serve as decimal markers. These are painted red on one side and the same light gray as the plate on the other. To the right of and below the number keys are a variety of function keys, including addition and subtraction bars, keys for moving the carriage, an enter key, a repeat and a non-repeat button, and diverse other keys for division and multiplication.
Behind the keyboard is a carriage with a row of eight dials to show a number set up for multiplication, a row of 16 dials to show the result, and a row of eight revolution register dials. These are visible through windows in the carriage. The set up dials for multiplication have a metal frame that slides over them to indicate the position of the decimal point and two digits to the right of the decimal point. It can be placed in seven different positions. A gray plastic knob is at the back on the right side.
A mark on the front and back of the machine reads: MONROE. On the back, it is a trademark registered by Monroe in 1956. A mark on the right and left sides reads: MONROmatic. A paper tag glued to the bottom of the machine reads: MONROE (/) CALCULATING MACHINE (/) COMPANY, INC. (/) ORANGE, N.J. U.S.A.; It also has several patent numbers, the largest of which is 2,931,569, the number of a 1955 patent. A metal tag attached to the bottom reads: MODEL CSA 8 (/) SERIAL B930371. In 1958 Monroe became a subsidy of Litton Industries. Many Monroe calculating machines with serial numbers beginning in B date from the 1960s.
Reference:
Documentation received with the machine, with museum numbers MA.318943.02 through MA.318943.06. This includes an invoice, indicating that it was repaired in 1970.
Location
Currently not on view
date made
1957
maker
Monroe International Corporation, a Division of Litton Business Systems
Monroe Calculating Machine Company
ID Number
MA.335384
catalog number
335384
maker number
B930371
accession number
318943

Curta Type II Calculating Machine

This compact cylindrical handheld calculating machine has gray metal sides and a black top and operating handle. There are 11 slots along the side of the cylinder with plastic red and black levers that are pulled down to set numbers.
Description
This compact cylindrical handheld calculating machine has gray metal sides and a black top and operating handle. There are 11 slots along the side of the cylinder with plastic red and black levers that are pulled down to set numbers. The digit entered appears at the top of the slot. Multipliers are indicated by numbers read through holes around the edge of the top and may be up to eight digits large. The result also is indicated around the edge of the top, and may be up to 15 digits large. The top may be rotated, as one one would move a carriage on an earlier stepped drum machine. Sliding markers indicate decimal divisions for entries, multipliers, and results.
To zero the machine, the carriage is raised and the black disc under the operating lever is rotated through one turn using a clearing lever with a ring-like handle. The operating handle is pulled up for subtraction and division. Moving a lever on the side of the cylinder causes subtraction rather than addition in the revolution counting register. Operating instructions were received with the machine and are stored with it. The machine fits in a black metal cylindrical case. The lid of the case turns clockwise to open.
The machine and case are marked: CURTA, A mark on the bottom of the object reads: Type II (/) No 517304 (/) Made in Liechtenstein (/) (Customs Union with Switzerland) (/) by Contina Ltd Mauren (/) System Curt Herstark. The machine is marked on the lid: OPEN.
The Curta calculating machine was invented the Austrian Curt Hertzstark (1902–1988). He worked on the design during World War II as a prisoner at the Nazi concentration camp of Buchenwald, and produced the machine after the war in Liechtenstein. The Curta Type II was sold from at least 1954 until early 1972, when handheld electronic calculators replaced it.
For related documentation, see 1983.0471.06 and 1983.0471.07
References:
Curt Hertstark, Interview with Erwin Tomash, September 10 and 11, 1987, Oral History 140, Charles Babbage Institute, Minneapolis, Minnesota. Hertstark dates the beginning of production of the Curta to 1949.
Cliff Stoll, “The Curious History of the First Pocket Calculator,” Scientific American, (January 2004), pp. 82–89.
Location
Currently not on view
date made
ca 1958
maker
Contina AG Mauren
ID Number
1983.0471.05
accession number
1983.0471
catalog number
1983.0471.05

Monroe Model 8N-213 Calculating Machine

This fully automatic electric non-printing modified stepped drum calculating machine has a gray and black steel frame, and ten columns of gray and white oblong plastic keys. At the bottom of each column is a key for clearing it.
Description
This fully automatic electric non-printing modified stepped drum calculating machine has a gray and black steel frame, and ten columns of gray and white oblong plastic keys. At the bottom of each column is a key for clearing it. Between the columns of keys and under the keyboard are metal rods which turn to serve as decimal markers. They are painted white on one side and the same black as the case on the other.
To the right of the number keys are subtraction and addition bars, two carriage shift keys, and a green enter multiplier key. Below these are three levers, one to set repeated entries, one for multiplication, and one for non-entry. Below these are three red keys relating to entering the dividend, a gray keyboard clearance key, and a lock lever. Beneath the number keys are five keys relating to multiplication and division. A DIVD ALIGN key is left of these.
The carriage in back of the keyboard has ten dials to show a number set up for multiplication, 21 dials to show the result, and a row containing ten white dials and then 11 black dials. Sliding decimal markers are provided. The dials showing numbers set up for multiplication can be set at any of five positions. A metal piece slides over the windows for these dials to indicate the decimal point. A gray electrical cord attaches to the back. The gray cover is separate.
A mark on the carriage reads: MONROE. The same mark is on the back of the machine, with the Monroe logo trademarked in 1956. A mark on both right and left sides reads: MONROmatic. A paper sticker glued to the bottom of the machine reads: MONROE (/) CALCULATING MACHINE (/) COMPANY, INC. (/) ORANGE, N.J. U.S.A.. It also is marked with patent numbers that range from 2,250,403 to 2,732,129. The second patent date is from 1953. A metal tag attached to the bottom of the machine reads: MODEL 8N-213 (/) SERIAL B973812B. There is no mention of Litton Industries, which acquired Monroe Calculating Machine Company in 1958.
According to the accession file, the machine was purchased by the University of Pittsburgh 14 September 1960, at a cost of $880, for use in parapsychological research.
Compare to MA.335425 and 1984.3046.01.
Reference:
Accession file.
Location
Currently not on view
date made
1960
maker
Monroe Calculating Machine Company, Inc.
ID Number
1980.0255.01
catalog number
1980.0255.01
maker number
B973812B
accession number
1980.0255

Friden Model STW 10 Calculating Machine

This full-keyboard, electric non-printing calculating machine has a metal frame painted gray-brown and ten columns of color-coded brown and light tan plastic number keys, with a blank light tan key at the bottom of each column.
Description
This full-keyboard, electric non-printing calculating machine has a metal frame painted gray-brown and ten columns of color-coded brown and light tan plastic number keys, with a blank light tan key at the bottom of each column. Metal rods between the columns of keys and under the keyboard turn to indicate decimal places. A small brown and tan bar slides to the right to reset the decimal rods. On the right are two columns of function bars. The capabilities of the Friden STW-10 are quite similar to those of the earlier ST-10, although the exterior design and color are different.
On the left is a ten-digit register that indicates numbers entered for multiplication. Below it is a block of nine tan digit keys, with a 0 bar below. These are surrounded by three levers and four function keys.
Behind the number keys is a movable carriage with an 11-digit revolution register and a 20-digit result register. Gray-brown plastic buttons above the result register rotate to set up numbers. Ten numbered buttons are under the revolution register as well. Zeroing knobs for the registers are on the top right of the carriage. All three registers have sliding decimal markers.
The donor reported a date for the machine of 1960 and said that the initial price was $880. Jorgenson gives the same date. Carl Holm gives 1956 the date of manufacture.
Compare MA.334379, MA.335419 and 1984.3079.04.
References:
Accession File.
Ernie Jorgenson., Friden Age List, Office Machine Americana, p. 5.
Carl Holm, “Milestones in the Development of Friden.”
Location
Currently not on view
date made
1960
maker
Friden Calculating Machine Company
ID Number
MA.335419
accession number
319049
maker number
STW 10 635028
catalog number
335419

Monroe Model 8N-213 Calculating Machine

This fully automatic, non-printing electric modified stepped drum calculating machine has a gray and black steel frame and ten columns of gray and white oblong plastic keys. At the bottom of each column is a clearance key.
Description
This fully automatic, non-printing electric modified stepped drum calculating machine has a gray and black steel frame and ten columns of gray and white oblong plastic keys. At the bottom of each column is a clearance key. Between the columns of keys and under the keyboard are metal rods that turn to serve as decimal markers. An automatic keyboard clear switch is in the front. To the right of the number keys are subtraction and addition bars, two carriage shift keys, and a green key. Below these are three levers, one to set repeated entries, one for multiplication, and one for non-entry. Below these are three red keys relating to entering the dividend, a gray keyboard clear key, and a lock lever. Beneath the number keys are five keys relating to multiplication and division. A DIVD ALIGN key is left of these.
In back of the keyboard is a carriage with ten dials to show a number set up for multiplication, 21 dials to show the result, and a row containing ten white dials on the left and then 11 black dials. The white dials are revolution register dials that show multipliers in black or quotients in red. These do not have a carry. The black dials also register the multiplier in multiplication and the quotient in division and have a carry. Above the black dials is a row plastic buttons, eight red and one yellow. The red buttons are tab stops for the carriage, and the yellow button releases the red ones. Sliding decimal markers are provided. A gray-green electric cord plugs into the back of the machine.
A mark on the carriage reads: MONROE. The same mark is on the back of the machine, with the Monroe logo trademarked in 1956. A mark on both right and left sides reads: MONROmatic. A paper sticker glued to the bottom of the machine reads: MONROE (/) CALCULATING MACHINE (/) COMPANY, INC. (/) ORANGE, N.J. U.S.A.. It also is marked with patent numbers that range from 2,250,403 to 2,732,129. The second patent date is from 1953. A metal tag attached to the bottom of the machine reads: MODEL 8N-213 (/) SERIAL J903574. There is no mention of Litton Industries, which acquired Monroe Calculating Machine Company in 1958.
Compare to 335425 and 1980.0255.01.
Location
Currently not on view
date made
ca 1960
maker
Monroe Calculating Machine Company, Inc.
ID Number
1984.3046.01
catalog number
1984.3046.01
maker number
J903574
nonaccession number
1984.3046

Monroe Model 8N-213 Calculating Machine

This fully automatic electric non-printing, modified stepped drum calculating machine has a steel frame in two shades of gray and ten columns of gray and white oblong plastic keys. At the bottom of each column is a key for clearing it.
Description
This fully automatic electric non-printing, modified stepped drum calculating machine has a steel frame in two shades of gray and ten columns of gray and white oblong plastic keys. At the bottom of each column is a key for clearing it. An automatic keyboard clear switch is at the front. Between the columns of keys and under the keyboard are metal rods that turn to serve as decimal markers. To the right of the number keys are subtraction and addition bars, two carriage shift keys, and a green enter multiplier key. Below these are three levers, one to set repeated entries, one for multiplication, and one for non-entry. Below these are three red keys relating to entering the dividend and a gray keyboard clear key. Beneath the number keys are five keys relating to multiplication and division. A DIVD ALIGN key is left of these.
In back of the keyboard is a carriage with a ten dials to show a number set up for multiplication, 21 dials to show the result, and a row containing ten white dials on the left and then 11 black dials. The white dials are revolution register dials that show multipliers in black or quotients in red. These do not have a carry. The black dials also register the multiplier in multiplication and the quotient in division and have a carry. Above the black dials is a row of 8 red and one yellow plastic buttons. The red buttons are tab stops for the carriage, and the yellow button releases the red ones. Sliding decimal markers are provided. A black electrical cord plugs into the back of the machine.
A mark on the carriage reads: MONROE. The same mark is on the back of the machine, with the Monroe logo trademarked in 1956. A mark on both right and left sides reads: MONROmatic. A paper sticker glued to the bottom of the machine reads: MONROE (/) CALCULATING MACHINE (/) COMPANY, INC. (/) ORANGE, N.J. U.S.A.. It also is marked with patent numbers that range from 2,250,403 to 2,732,129. The second patent date is from 1953. A metal tag attached to the bottom of the machine reads: MODEL 8N-213 (/) SERIAL J905667. There is no mention of Litton Industries, which acquired Monroe Calculating Machine Company in 1958.
Compare to 1980.0255.01 and 1984.3046.01.
Location
Currently not on view
date made
ca 1960
maker
Monroe Calculating Machine Company, Inc.
ID Number
MA.335425
catalog number
335425
maker number
J905667
accession number
319049

Monroe Model IQ-213 Calculating Machine

Authors in the 19th century marveled that machines could carry out arithmetic operations, which had often been associated purely with human intelligence.
Description
Authors in the 19th century marveled that machines could carry out arithmetic operations, which had often been associated purely with human intelligence. In the mid-20th century the Monroe Calculating Machine Company, a division of Litton Industries, introduced an electrically operated calculating machine that could store numbers entered to be used in several mathematical operations. They hailed this memory feature of calculating machines as an extension of artificial intelligence, naming the machine the “IQ-213.”
The full-keyboard, non-printing and electrically operated modified stepped drum calculating machine has a dark gray metal frame with a light gray metal carriage and keyboard. The keys are plastic. The ten columns of color-coded digit keys have nine keys in each column. Ten numeral dials on the keyboard display the amount entered in the memory. The machine has some 18 function keys.
The movable metal carriage has a row of nine plastic tab stops above three rows of dials. The top row of dials is divided into two sections, with ten dials on the left and 11 to the right. The left dials are revolution register dials that show multipliers in black or quotients in red. These do not have a carry. The right dials also register the multiplier in multiplication and the quotient in division and have a carry.
Above the black right dials is a row of eight red and one yellow plastic buttons. The red buttons are tab stops for the carriage, the yellow button releases the red ones. The second row contains 21 dials (for the results of addition, subtraction, and multiplication), and the third row has ten dials (for the multiplier). A cord that plugs into the back and a light tan plastic cover are present.
The machine is marked in raised letters on the front and back: MONROE; IQ-213 (/) THE CALCULATOR WITH A MEMORY. It is marked on both sides: MONROmatic. A tag attached to the bottom of the case reads: MODEL IQ - 213 (/) SERIAL B852353. The cord and plastic cover are marked: MONROE li.
For related documentation, see pamphlet 1988.0663.02, which is copyrighted 1963. Monroe filed for a trademark for the phrase “IQ-213” in 1962, and obtained the registration in 1963.
This machine was purchased by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, from Litton Business Systems for $1,085.
References:
Accession file.
U.S. Patent and Trademark Office, Trademark Registration Number 754123, August 6, 1963.
Location
Currently not on view
date made
1963
maker
Litton Industries
ID Number
1988.0663.01
catalog number
1988.0663.01
maker number
B852353
accession number
1988.0663

Friden Model SBT 10

This modification of Friden’s fully automatic STW calculating machine allows for “back transfer.” That is to say, it has a mechanism to transfer figures from the accumulator register to the keyboard selecting levers and vice versa.
Description
This modification of Friden’s fully automatic STW calculating machine allows for “back transfer.” That is to say, it has a mechanism to transfer figures from the accumulator register to the keyboard selecting levers and vice versa. The model was manufactured from 1959 until 1965.
The full-keyboard electric non-printing stepped drum machine has a metal frame painted tan and ten columns of brown and white plastic keys, with a blank white key at the bottom of each column. Metal rods between the columns of keys and under the keyboard turn to indicate decimal points. On the right are two columns of function bars. On the left is a nine-digit register that indicates numbers entered for multiplication. Below it is a block of nine white digit keys, with a 0 bar below. These are surrounded by further levers and function keys, including a split “NEG POS TRANSFER” bar.
Behind the entry keys is a movable carriage with an 11-digit register and a 20-digit result register. The result register has plastic buttons above it that can be used to set up numbers. Nine entry buttons and a clear button are under the revolution register. Zeroing knobs for the registers are on the right of the carriage. A clear carriage bar is toward the front of the keyboard. All three registers have sliding decimal markers. The machine has four hard rubber feet as well as a rubber cord and a tan plastic cover.
A mark on the bottom reads: MODEL SERIAL (/) SBT 10 907698. A mark on the back and side reads: Friden. A sticker on the bottom reads: FRIDEN, INC. (/) SAN LEONARDO, CALIFORNIA, USA. A mark on the cover reads: Friden (/) AUTOMATIC CALCULATOR.
For related documents, see 1984.0475.02, 1984.0475.03, 1984.0475.07, and non-accession 1984.3079.
This is one of five Friden calculating machines given to the Smithsonian by Vincent L. Corrado (1917-1984), a native of Covington, Kentucky, who earned bachelor’s and master’s degrees in accounting at Catholic University, served in the U.S. Army from 1942 through 1973, and then joined the Veteran’s Administration for the rest of his life.
The date given is based on the serial number, courtesy of Carl Holm. This is the date of manufacture.
Reference:
Ernie Jorgenson, Friden Age List, Office Machine Americana, p. 5 gives the date 1960 for this machine.
Location
Currently not on view
date made
1964
maker
Friden, Inc.
ID Number
1983.0475.01
catalog number
1983.0475.01
accession number
1983.0475
maker number
SBT 10 907698

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