Science & Mathematics

The Museum's collections hold thousands of objects related to chemistry, biology, physics, astronomy, and other sciences. Instruments range from early American telescopes to lasers. Rare glassware and other artifacts from the laboratory of Joseph Priestley, the discoverer of oxygen, are among the scientific treasures here. A Gilbert chemistry set of about 1937 and other objects testify to the pleasures of amateur science. Artifacts also help illuminate the social and political history of biology and the roles of women and minorities in science.

The mathematics collection holds artifacts from slide rules and flash cards to code-breaking equipment. More than 1,000 models demonstrate some of the problems and principles of mathematics, and 80 abstract paintings by illustrator and cartoonist Crockett Johnson show his visual interpretations of mathematical theorems.

The manual, full-keyboard non-printing modified stepped drum calculating machine has a metal frame painted black and a steel keyboard painted green. Eight columns of uniformly shaped black and white color-coded keys serve for data entry.
Description
The manual, full-keyboard non-printing modified stepped drum calculating machine has a metal frame painted black and a steel keyboard painted green. Eight columns of uniformly shaped black and white color-coded keys serve for data entry. At the bottom of each column is a red clearance key. Metal rods between the rows of keys are decimal markers. Three key stems are in a column to the right of the number keys. One clears the entire keyboard. The other two are set to determine whether or not the keyboard clears after each calculation (at least one of these keys looks like a replacement). A metal lever is right of the keyboard and a metal knob to the left. The operating crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
The carriage behind the keyboard has a row of 16 black numeral dials for recording results, and a row of eight white numeral dials which serve as a revolution register. The revolution register, which has no carry, has black digits for addition and red ones for subtraction. Two thin metal rods between the windows for these registers carry decimal markers. The carriage shift crank is at the front of the machine. A knob for lifting the carriage is right of the result register, and a crank for zeroing dials on the carriage is on its right side. There are four rubber feet. A bell rings when the result passes through zero (as in over-division).
A mark on the front of the machine reads: MONROE. A mark on the back reads: MONROE (/) Calculating Machine Company (/) New York, U.S.A. The serial number, recorded on the bottom edge of the left side of the carriage, is 91928
Reference:
J. H. McCarthy, The Business Machines and Equipment Digest, 1928, pp. 9-29 to 9-33.
Location
Currently not on view
date made
1927
maker
Monroe Calculating Machine Company
ID Number
1984.0682.05
catalog number
1984.0682.05
maker number
91928
accession number
1984.0682
This example of Monroe Calculating Machine Company’s Model K-20 calculating machine was lent to the Smithsonian in 1922 as an example of one of the company’s latest products.The manually operated, full-keyboard, modified stepped drum machine has a metal (not steel) frame painted
Description
This example of Monroe Calculating Machine Company’s Model K-20 calculating machine was lent to the Smithsonian in 1922 as an example of one of the company’s latest products.
The manually operated, full-keyboard, modified stepped drum machine has a metal (not steel) frame painted black, with rounded corners. It slopes downward from back to front. The steel plate under the keyboard is painted green. The ten columnsof plastic keys are colored black or white according to the place value of the digit represented. A red clearance key is at the bottom of each column. Keystems are of uniform length. Rods between the rows of keys serve as decimal markers. They are painted green on one side to match the plate under the keyboard, and unpainted on the other side.
A column to the right of the number keys has three keys. One clears the entire keyboard. The other two are set to determine whether or not the keyboard clears after each calculation. A metal lever is to the right of the keyboard and a metal knob to the left. The operating crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
In back of the keyboard is a carriage that has a row of 20 numeral dials for recording results, and a row of ten numeral dials behind these which serve as a revolution register. Two thin metal rods between the windows carry decimal markers. The carriage shift crank 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 on the carriage is further to the right. This crank lifts the carriage as it resets the dials. The machine has four rubber feet.
A mark at the center front reads: MONROE (/) Calculating Machine Company (/) New York,U.S.A. A mark at the center of the back reads: MONROE. The serial number, 50885, stamped the on right side of the mechanism of the machine, under the carriage, is difficult to read.
Compare MA.334711, MA.307386, 1983.0831.01, and 1982.0682.05..
Reference:
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, p. 551.
Location
Currently not on view
date made
1921
maker
Monroe Calculating Machine Company
ID Number
MA.307386
catalog number
307386
maker number
50185
accession number
2011.0209
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
This is an early model of the full-keyboard, modified stepped drum, manually operated non-printing calculating machine manufactured by the Monroe Calculating Machine Company on patents of Frank S. Baldwin.The machine has a steel frame painted black.
Description
This is an early model of the full-keyboard, modified stepped drum, manually operated non-printing calculating machine manufactured by the Monroe Calculating Machine Company on patents of Frank S. Baldwin.
The machine has a steel frame painted black. The eight columns of plastic keys are colored black or white according to the place value of the digit represented. The key stems are banked, standing up further toward the back of the machine. At the front of the keyboard is a row of red keys each of which clears the column above it. On the right side, in this row, is a red key for clearing the entire keyboard. There are no strips between columns of keys. Two silver-colored knobs have arrows on them. The one on the right is used for automatic keyboard release in continuous addition. The one on the left is the register key for the item counter.
In back of the keyboard is a carriage with 16 black total register dials and eight revolution register dials behind the total dials. The dials of the revolution register are numbered around the edge from 9 to 0 white and from 9 to 1 in red. The metal operating handle with a wooden knob painted brown is on the right side. Another handle on the right side of the carriage zeros the total register or the revolution register, depending on the direction in which it is turned. There is no knob to lift the carriage. An all-metal crank at the front of the machine is rotated to move the carriage. The carriage has sliding decimal markers for both registers.
The machine is marked at the center of the back edge, underneath the carriage: 20. A mark on the front reads: MONROE (/) Calculating Machine Company (/) New York. There is no mention of a trademark. A sticker on the back reads: PATENTED JUNE 16, 1908 (/) OTHER U.S. AND FOREIGN PATENTS (/) PENDING.
Compare to MA.317389. Both machines have the same number of keys, the same number of entries in the revolution counter and result registers, and the same mark on the sticker on the back. The mark on MA.317389 mentions a trademark. The color-coding of the keys, the color of the machine handles and shift lever, and the mechanism for the carriage shift differ between the machines. Object MA.317389 has rotating rods that serve as decimal dividers on the keyboard, and a considerably larger serial number, which begins with a D. Hence that machine is given a slightly later date.
Reference:
E. Martin, The Calculating Machines (Die Rechenmaschinen), trans. P. A. Kidwell and M. R. Williams, Cambridge: MIT Press, 1992, p. 265.
Location
Currently not on view
date made
1914
maker
Monroe Calculating Machine Company
ID Number
MA.307385
catalog number
307385
maker number
none found
accession number
67982
This is an early model of the full-keyboard, modified stepped drum, manually operated, non-printing calculating machine manufactured by the Monroe Calculating Machine company on patents of Frank S. Baldwin.The machine has a steel frame, painted black.
Description
This is an early model of the full-keyboard, modified stepped drum, manually operated, non-printing calculating machine manufactured by the Monroe Calculating Machine company on patents of Frank S. Baldwin.
The machine has a steel frame, painted black. The eight columns of plastic keys are colored black or white according to the place value of the digits represented. The key stems are banked, standing up further toward the back of the machine. At the front of the keyboard is a row of red keys, each of which clears the column above. On the right side, in this row, is a red key for clearing the entire keyboard.
Behind each column of keys is a double disc with teeth of varying length protruding from it that serves as a stepped drum. One disc has five teeth on it, and the other has four. Pushing the appropriate key causes one or both of the discs to approach one another so that they are engaged when a crank on the right side turns, entering the appropriate number into the mechanism.
Between the rows of keys are metal strips, painted black on one side and white on the other. They rotate to serve as decimal markers. Two silver-colored knobs have arrows on them. The one on the right is used for automatic keyboard release in continuous addition. The one on the left is the register key for the item counter.
In back of the keyboard is a carriage with 16 black total register dials and eight white and red revolution register dials behind the total dials. Between the windows for these registers are two thin metal rods that carry decimal markers. Another handle on the right side of the carriage zeros the total register or the revolution register, depending on the direction in which it is turned. A knob on the right side of the carriage is used to lift it. A crank at the front of the machine rotates to move the carriage.
A mark on the front of the machine reads: MONROE (/) REGISTERED TRADEMARK (/) Calculating Machine Company (/) New York, U.S.A. A sticker toward the left on the carriage reads in ink: CLEARING. A mark at the center of the back reads: D1749. A mark under the carriage on the right reads: 1749. A sticker on the back of the machine reads: PATENTED JUNE 16, 1908 (/) OTHER U.S. AND FOREIGN PATENTS (/) PENDING.
Compare MA.307385. The latter machine has a different carriage shift mechanism, a lower serial number, and a different color-coding of the keys. It has no decimal dividing rods between the keys, and no mention of a trademark. It has a different way of marking decimal divisions on the carriage and has been assigned a slightly earlier date.
Monroe first used the name Monroe to describe its products in 1913. The company applied for a trademark on April 7, 1919, and was granted it onJanuray 20, 1920.
References:
E. Martin, The Calculating Machines (Die Rechenmaschinen), trans. P. A. Kidwell and M. R. Williams, Cambridge: MIT Press, 1992, p. 265.
U.S. Patent and Trademark Office, Trademark Registration 129029, Serial #71117235.
Location
Currently not on view
date made
1915
maker
Monroe Calculating Machine Company
ID Number
MA.317389
catalog number
317389
maker number
D1749
accession number
230394
This full-keyboard, electric, non-printing modified stepped drum calculating machine has a steel frame painted black, with rounded corners. The metal plate under the keyboard is painted green.
Description
This full-keyboard, electric, non-printing modified stepped drum calculating machine has a steel frame painted black, with rounded corners. The metal plate under the keyboard is painted green. The six columns of plastic keys are colored black or white according to the place value of the digit represented. A red clearance key is at the bottom of each column. Rods between the rows of keys serve as decimal markers. They are unpainted on one side and painted the same green as the plate under the keyboard on the other.
A column to the right of the number keys has three keys. One clears the entire keyboard. The other two are set to determine whether or not the keyboard clears after each calculation. Above these are plastic bars which may be depressed for electric addition or subtraction. The machine also operates using a removable crank that fits on the right side and rotates clockwise for addition and counterclockwise for subtraction.
In back of the keyboard is a carriage that has a row of 12 numeral dials for recording results and a row of six numeral dials behind these, which serve as a revolution register. The revolution register has no carry. Two thin metal rods between the windows for these registers carry decimal markers. The carriage shift lever is at the front of the machine. To the right of the result register is a knob for lifting the carriage. On the right side of the carriage is the zeroing crank for dials on it. The machine has four rubber feet. The motor is attached to the left side of the machine and has an on-off switch. It has a fraying electrical cord attached. The on-off switch for the bell is on the back left of the keyboard.
A mark on the center back of the machine reads: MONROE (/) Calculating Machine Company (/) New York, U.S.A. A mark on the left bottom edge of the carriage and on the right side of the machine under the carriage gives the serial number A20317. The machine is from after 1924 and before 1939. In the later years, it was known as the KA-120.
Reference:
J. H. McCarthy, The Business Machines and Equipment Digest, 1928, pp. 9-29 to 9-33.
Location
Currently not on view
date made
ca 1930
maker
Monroe Calculating Machine Company
ID Number
MA.323614
catalog number
323614
maker number
A20312
accession number
250163
This promotional white plastic six-inch ruler is divided along the top edge to sixteenths of an inch and numbered by fourths from 1 to 6. The ruler is marked: MONROE CALCULATING MACHINE COMPANY, INC.
Description
This promotional white plastic six-inch ruler is divided along the top edge to sixteenths of an inch and numbered by fourths from 1 to 6. The ruler is marked: MONROE CALCULATING MACHINE COMPANY, INC. (/) CALCULATING • ADDING • ACCOUNTING • BOOKKEEPING • CHECK WRITING MACHINES (/) J. C. Fleming, Representative 1320 Eighteenth Street, N.W., Washington, D.C., COlumbia 5-1222. A list of decimal equivalents of fractions is on the back of the ruler. Below the list is the Monroe logo and the words: MADE IN U.S.A.
In 1912, Jay Randolph Monroe purchased a factory in Orange, N.J., to manufacture mechanical calculators on a design by Frank Stephen Baldwin. The Monroe Calculating Machine Company quickly became a leader in its field, opening sales offices around the world and building additional factories in Virginia and Amsterdam, The Netherlands. Litton Industries purchased the firm in 1958, changed its name to Monroe Systems for Business in 1980, and sold it in 1984 to Jeffry M. Picower.
The company refocused on calculators in 1998 and was purchased by Carolina Wholesale Office Machine Company in 2001. J. C. Fleming was presumably the Monroe sales agent for Washington, D.C. The Smithsonian collections include 25 Monroe calculating machines and over 30 pieces of related documentation. For promotional rulers by Monroe's chief competitors, see MA.293320.2811, MA.293320.2813, and MA.293320.2816. Large American cities used postal zone numbers from 1943 to 1963, hence the dating of the object.
References: Frank S. Baldwin, "Calculating and Recording Machine" (U.S. Patent 890,888 issued June 16, 1908); John Wolff, "The Monroe Calculating Machine Company," May 27, 2012, John Wolff's Web Museum, http://home.vicnet.net.au/~wolff/calculators/Monroe/Monroe.htm; Monroe Systems for Business, "History," http://www.monroe-systems.com/history/.
Location
Currently not on view
date made
1943–1963
distributor
Monroe Calculating Machine Company
maker
Monroe Calculating Machine Company
ID Number
MA.293320.2812
catalog number
293320.2812
accession number
293320
This full-keyboard manually operated non-printing modified stepped drum calculating machine has a steel frame painted black. The eight columns of round plastic keys are colored black or white according to the place value of the digit represented.
Description
This full-keyboard manually operated non-printing modified stepped drum calculating machine has a steel frame painted black. The eight columns of round plastic keys are colored black or white according to the place value of the digit represented. The key stems are banked, standing up further toward the back of the machine. A row of red clearance keys is at the front of the keyboard; a red key for clearing the entire keyboard is on the right side. Between rows of keys are metal strips, painted black on one side and white on the other, that turn to serve as decimal markers. Ther two silver-colored knobs have arrows on them. One on the right is used for automatic keyboard release in continuous addition. One on the left is the register key for the item counter.
A carriage behind the keyboard has 16 black total register dials and eight white revolution register dials. The revolution register has black digits for addition and red ones for subtraction. A metal operating handle with a wooden knob is on the right side. Another handle on the right side of the carriage zeros the total register or the revolution register, depending on the direction in which it is turned. A knob on the right side of the carriage is used to lift it. A crank at the front of the machine rotates to move the carriage. The machine has four rubber feet.
A partly obliterated mark on the front reads: MONROE (/) REGISTERED TRADEMARK (/) Calculating Machine Company (/) New York, U.S.A. A mark in the middle of the back of machine reads: E5681.
This particular machine came to the Smithsonian from Feldman’s Department Store in Baltimore, Maryland, when the then fifty-year old family business was liquidated in 1974.
According to McCarthy, Monroe began manufacturing the Model E in 1916, using serial numbers beginning at 4,000. Monroe received a registered trademark for its machines in 1920, and began marking objects to that effect. In 1921 it replaced its earlier models with the model K. Hence the date assigned.
References:
E. Martin, The Calculating Machines (Die Rechenmaschinen), trans. P.A. Kidwell and M.R. Williams, Cambridge: MIT Press, 1992, p. 265.
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, pp. pp, 80–81, 551.
U.S. Patent and Trademark Office, Trademark Registration 129029, Serial #71117235.
Accession file.
Location
Currently not on view
date made
1916
maker
Monroe Calculating Machine Company
ID Number
MA.334403
catalog number
334403
maker number
E5681
accession number
316382
This full-keyboard, non-printing manually operated modified step drum calculating machine has a steel frame painted black. The eight columns of plastic keys are colored black or white according to the place value of the digit entered.
Description
This full-keyboard, non-printing manually operated modified step drum calculating machine has a steel frame painted black. The eight columns of plastic keys are colored black or white according to the place value of the digit entered. The key stems are banked, standing up further toward the back of the machine.
At the front of the keyboard is a row of red clearance keys for the individual columns above. On the right side is a red key for clearing the entire keyboard. Between the rows of keys are metal strips, painted black on one side and white on the other. They turn to serve as decimal markers. The two silver-colored knobs have arrows on them. The one on the right is used for automatic keyboard release in continuous addition. The one on the left is the register key for the item counter.
In back of the keyboard is a carriage with 16 black total register dials and eight white revolution register dials behind the total dials. The revolution register dials are numbered around the edge from 0 to 9 in white and then from 9 to 1 in red. Metal strips on the carriage carry sliding decimal markers for the registers. Ther metal operating handle with a wooden knob is on the right side. Another handle on the right side of the carriage zeros the total register or the revolution register, depending on the direction in which it is turned. A shaped metal piece on the left side of the carriage is used to lift it. A crank at the front of the machine rotates to move the carriage.
A mark on the front of the machine reads: MONROE (/) Calculating Machine Company (/) New York. A mark in the middle of the back reads: F6981. A tag on the back of the machine reads: PATENTED JUNE 16, 1908 (/) OTHER U.S. AND FOREIGN PATENTS (/) PENDING. A mark on the plastic cover reads: MONROE.
According to McCarthy, the Monroe Model F was introduced in 1917, with serial numbers above 6,000. In 1920, Monroe was granted a trademark for the name Monroe, and used the term “registered trademark” on its machines. Hence the approximate date assigned to this machine.
References:
E. Martin, The Calculating Machines (Die Rechenmaschinen), trans. P. A. Kidwell and M. R. Williams, Cambridge: MIT Press, 1992, p. 265.
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, pp. 80–81, 551.
U.S. Patent and Trademark Office, Trademark Registration 129029, Serial # 71117235.
Location
Currently not on view
date made
ca 1918
maker
Monroe Calculating Machine Company
ID Number
MA.323609
catalog number
323609
maker number
F6981
accession number
250163
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
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
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
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
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
This manually operated, non-printing modified step drum calculating machine has a steel case with plastic keys and wooden handles on the cranks. In the eight columns of keys, the key stems increase in length from front to back.
Description
This manually operated, non-printing modified step drum calculating machine has a steel case with plastic keys and wooden handles on the cranks. In the eight columns of keys, the key stems increase in length from front to back. On the right side is a red key for clearing the entire keyboard. Between the rows of keys are metal strips, painted black on one side and white on the other. They turn to serve as decimal markers. Two silver-colored knobs have arrows on them. The one on the right is used for automatic keyboard release in continuous addition. The one on the left is the register key for the item counter.
In back of the keyboard is a carriage with 16 total register dials and eight revolution register dials behind the total 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 metal operating handle with a wooden knob is on the right side. Another handle on the right side of the carriage zeros the total register or the revolution register, depending on the direction in which it is turned. A knob on the right side of the carriage is used to lift it. A crank at the front of the machine is rotated to move the carriage. The machine has four rubber feet.
A mark on the front of the machine reads: MONROE (/) REGISTERED TRADE MARK (/) HIGH SPEED-ADDING-CALCULATOR. A mark on the back of the machine reads: MONROE (/) REGISTERED TRADE MARK (/) CALCULATING MACHINE COMPANY (/) New York, U.S.A. Another mark on the back reads: G22939.
According to McCarthy, Monroe introduced the Model G calculating machine in 1919, using serial numbers above 20,000. Records of the U.S. Patent and Trademark Office indicate that the trademark Monroe was registered in 1920. In 1921 Monroe replaced the Model G and other earlier models with its Model K, hence the date assigned.
The donor of the machine reported that he purchased it used at a flea market or tag sale.
References:
E. Martin, The Calculating Machines (Die Rechenmaschinen), trans. P.A. Kidwell and M.R. Williams, Cambridge: MIT Press, 1992, p. 265.
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, pp. 80–81, 551.
U.S. Patent and Trademark Office, Trademark Registration 129029, Serial #71117235.
Location
Currently not on view
date made
1920
maker
Monroe Calculating Machine Company
ID Number
1988.3061.01
catalog number
1988.3061.01
maker number
G22939
nonaccession number
1988.3061
This full-keyboard manually operated non-printing modified stepped drum calculating machine is a Monroe Model K, especially altered for use by the blind. It was owned by Russell Kletzing of Sacramento, Calif., a lawyer blinded as a child.
Description
This full-keyboard manually operated non-printing modified stepped drum calculating machine is a Monroe Model K, especially altered for use by the blind. It was owned by Russell Kletzing of Sacramento, Calif., a lawyer blinded as a child. Kletzing was active in the National Federation of the Blind, and challenged the view that the U.S. Civil Service register should exclude blind lawyers because they could not read conventionally printed text.
The machine has a metal frame painted black, with rounded corners. The steel plate under the keyboard is painted green. The eight columnsof plastic keys are colored black or white accoding to the place value of the digit represented. The “5” digit keys have a raised metal dot on them. Key stems for clearance keys are at the bottom of each column, but have no key tops. Rods between the rows of keys to serve as decimal markers are lacking. Three keys in a column to the right of the number keys include one that clears the entire keyboard, with the other two set to determine whether or not the keyboard clears after each calculation. A metal lever is to the right of the keyboard and a metal knob to the left. The operating crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
Behind the keyboard is a carriage that has a row of 16 numeral dials for recording results and a row of eight numeral dials behind for the revolution register. The revolution register dials are each numbered from 0 to 9 in black and from 1 to 9 in red. Fixed indentations between the revolution dials serve as decimal markers. Both of these sets of dials have digits in Braille as well as typeface. The carriage has no sliding decimal markers. Small paper stickers have been glued below the usual position of the decimal point and the thousands marker in the result register. The carriage shift lever is at the front of the machine. The carriage has a knob for lifting it to the right of the result register, and a crank for zeroing dials on its right side. The machine has four rubber feet.
A mark scratched on the back of the machine reads: Z265520. A mark on the right side of the mechanism, under the carriage, reads: Z97700. A mark on the bottom edge of the carriage at the left reads: 97700. A mark on the back of the machine, which has been painted over, reads: MONROE.
Compare to MA.334711 and MA.307386.
References:
J. H. McCarthy, American Digest of Business Machines, 1924, pp. 80–82, 551.
National Federation of the Blind, "NFB Awards 2000," Braille Monitor, August / September 2000.
Location
Currently not on view
date made
ca 1928
maker
Monroe Calculating Machine Company
ID Number
1983.0831.01
maker number
Z97700
accession number
1983.0831
catalog number
1983.0831.01
This manual, full-keyboard non-printing modified stepped drum calculating machine has a metal frame painted black and a steel keyboard painted green.
Description
This manual, full-keyboard non-printing modified stepped drum calculating machine has a metal frame painted black and a steel keyboard painted green. In the six columns of black and white color-coded keys, keys for odd digits are concave and those for even digits are relatively flat. At the bottom of each column is a red clearance key. Metal rods between the rows of keys serve as decimal markers.
Three key stems are in a column to the right of the number keys. One clears the entire keyboard. The other two are set to determine whether or not the keyboard clears after each calculation. The keys for these key stems are missing. A metal lever is to the right of the keyboard and a metal knob to the left. The operating crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
The carriage in back of the keyboard has a row of 12 white numeral dials for recording results and a row of six numeral dials behind these in the revolution register. The revolution register has black digits for addition and red ones for subtraction. There is no carry in the revolution register. Two thin metal rods between the windows of these registers carry decimal markers. The carriage shift lever is at the front of the machine. To the right of the result register is a knob for lifting the carriage. A zeroing crank for dials on the carriage is on its right side. A bell rings when the result passes through zero (as in over-division). The machine has four rubber feet.
A mark on the front reads: MONROE. A mark on the back reads: MONROE (/) Calculating Machine Company (/) New York, U.S.A.. Stamped on the edge of the carriage on the back left is the serial number: 77811.
Reference:
J. H. McCarthy, The Business Machines and Equipment Digest, 1928, pp. 9-29 to 9-33.
Location
Currently not on view
date made
1926
maker
Monroe Calculating Machine Company
ID Number
1984.0682.04
catalog number
1984.0682.04
maker number
77811
accession number
1984.0682
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
This full-keyboard, non-printing, manual, modified stepped drum calculating machine has a metal frame painted black, with rounded corners. The eight columns of black and white plastic keys have a red clearance key at the bottom of each column.
Description
This full-keyboard, non-printing, manual, modified stepped drum calculating machine has a metal frame painted black, with rounded corners. The eight columns of black and white plastic keys have a red clearance key at the bottom of each column. Rotating rods between the rows of keys serve as decimal markers. Three keys are in a column to the right of the number keys. One clears the entire keyboard. The other two are set to determine whether or not the keyboard clears after each calculation. The operating crank on the right side rotates clockwise for addition and counterclockwise for subtraction.
In back of the keyboard is a carriage that has a row of 16 numeral dials for recording results and a row of eight numeral dials behind these that serves as a revolution register. Digits for the revolution register are red and black. Between the windows for these registers are two thin metal rods that carry decimal markers. The carriage shift lever is at the front of the machine. On the carriage, to the right of the result register, is a lifting knob. A crank on the right of the carriage for zeros registers on it. The machine has four rubber feet.
A mark on the front reads: MONROE. A red tag attached to it reads: PATENT DEPT. (/) #254. A white tag attached to it reads: Monroe Calculator 8 Banks (/) Hand Side Crank (/) #92701 (/) (A. Williamson) (/) Rack B Shelf #3.
This is model #254 from the Patent Division of Burroughs Corporation. Date based on assumption model number is 92701.
Compare to MA.334711, MA.307386, and 1983.0831.1.
Reference:
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, p. 551.
Location
Currently not on view
date made
1927
maker
Monroe Calculating Machine Company
ID Number
1982.0794.58
catalog number
1982.0794.58
accession number
1982.0794
In 1921 the Monroe Calculating Machine Company expanded its offerings to include calculating machines of several different capacities, selling the new machines as the model K. Soon thereafter, it began to sell automatic or electrically powered machines.
Description
In 1921 the Monroe Calculating Machine Company expanded its offerings to include calculating machines of several different capacities, selling the new machines as the model K. Soon thereafter, it began to sell automatic or electrically powered machines. This is an example of Monroe’s first electrically powered model, the KA.
The full-keyboard non-printing modified stepped drum machine has a metal frame painted black, with rounded corners. The steel plate under the keyboard is painted green. Eight columns of black and white plastic concave keys are colored according to the place value of the digit represented, with a red clearance key at the bottom of each column. Rods between the rows of keys serve as decimal markers. They are painted the same green as the plate underneath them on one side and white on the other.
To the right of the number keys are two bars and three keys in a column. The bars are for addition and subtraction. One key clears the entire keyboard. The other two are set to determine whether or not the keyboard clears after each calculation. A metal lever and a metal knob are to the left of the keyboard. A crank for operating the machine fits into the right side. It rotates clockwise for addition and counterclockwise for subtraction. A black motor attached to the left side at the back can be used to drive the machine. It has an on-off switch.
Behind the keyboard is a carriage that has a row of 16 numeral dials for recording results and a row of eight numeral dials behind these in the revolution register. Two thin metal rods between the rows of windows carry decimal markers. A 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 on the carriage is on its right side. The machine has four rubber feet and a black two-pronged electrical cord.
A mark on the front reads: MONROE (/) Calculating Machine Company (/) New York. The serial number, on the frame of the mechanism on the right side under the carriage is: A7530. A red tag attached to the object reads: PATENT DEPT. (/) #253. This is model #253 from the collection of the Patent Division of Burroughs Corporation.
Compare MA.334711, MA.304386, 1983.0831.1, and 1984.0682.05.
References:
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1924, p. 551.
J. H. McCarthy, The American Digest of Business Machines, Chicago: American Exchange Service, 1928, vol. 2, pp. 9-29 to 9-33.
Location
Currently not on view
date made
ca 1925
maker
Monroe Calculating Machine Company
ID Number
1982.0794.57
catalog number
1982.0794.57
maker number
A7530
accession number
1982.0794
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
This machine incorporates ideas of Purdue University graduate Clyde Gardner (1881-1923) who had a long career in the adding machine industry. He began as a draftsman at the Pike Adding Machine Company in 1903.
Description
This machine incorporates ideas of Purdue University graduate Clyde Gardner (1881-1923) who had a long career in the adding machine industry. He began as a draftsman at the Pike Adding Machine Company in 1903. By 1909, when Pike was acquired by the Burroughs Adding Machine Company, Gardner was chief engineer. He moved with the Pike plant to Detroit, where he worked as an engineer and patent expert at Burroughs.
In 1919 Gardner left Burroughs to work on his own design for an adding machine. On April 19, 1923, the Gardner Calculator Company was established in Ebensburg, Pennsylvania. Gardner died only two days later. His patents eventurally were acquired by the Monroe Calculating Machine Company, which manufactured this printing adding machine to complement its line of calculating machines.
The object has a green-black steel frame, a green keyboard, and 13 columns of black and white color-coded plastic number keys. To the right of the keyboard are total, error, and subtotal keys, and subtraction and addition bars. A non-add key is to the left of the keyboard. In back of the keyboard is a printing mechanism and a fixed carriage for the three-inch paper tape. The machine prints results of up to 14 digits. An asterisk printed next to a number indicates that it is a total. There is a black rubber-covered cord that plugs into the back.
The machine is marked on the front: MONROE (/) REGISTERED TRADE MARK. It is marked on a white sticker on the bottom of the machine: DATE (/) INSTALLED 10/Apr/57. It is marked on a gold sticker on the bottom of the machine: Licensed under Gubelman Patents. It is also marked there: 213-11-011-D (/) # 15128. According to the National Office Machine Blue Book, the serial number dates a Monroe machine to about 1932.
References:
American Office Machines Service vol. 3, 1937, 3.21. According to this source, the machine was introduced as the Gardner adding machine in 1924.
National Office Machine Blue Book, May, 1975, as compiled by Office Machine Americana, January 2002.
John E. Gable, History of Cambria County, Pennsylvania, Topeka, Kansas: Historical Publishing Company, 1926, pp. 781-782.
Location
Currently not on view
date made
1937
maker
Monroe Calculating Machine Company
ID Number
1987.0403.01
catalog number
1987.0403.01
accession number
1987.0403
This illustrated leaflet describes the 14 1/2 pound portable Model LA and Model LA-5 calculating machines.Currently not on view
Description
This illustrated leaflet describes the 14 1/2 pound portable Model LA and Model LA-5 calculating machines.
Location
Currently not on view
maker
Monroe Calculating Machine Company
ID Number
1979.3074.23
catalog number
1979.3074.23
nonaccession number
1979.3074
Each of these sheets describes a different Monroe calculating machine. The models described are the KAA Series 3, the LA-X, the Executive (e.g. the L 160-X, the L 200-x, and the L1207), and the MA.Currently not on view
Description
Each of these sheets describes a different Monroe calculating machine. The models described are the KAA Series 3, the LA-X, the Executive (e.g. the L 160-X, the L 200-x, and the L1207), and the MA.
Location
Currently not on view
date made
ca 1930s
maker
Monroe Calculating Machine Company
ID Number
1979.3074.22
catalog number
1979.3074.22
nonaccession number
1979.3074

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