Monroe Model LA5-160 Calculating Machine

Monroe Model LA5-160 Calculating Machine

Usage conditions apply
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.
Accession file.
National Office Machine Dealer’s Association, Blue Book, May, 1975, as compiled by Office Machine Americana, January, 2002.
Currently not on view
Object Name
calculating machine
date made
Monroe Calculating Machine Company
place made
United States: New York, New York City
Physical Description
wood (overall material)
aluminum (overall material)
plastic (overall material)
steel (overall material)
rubber (overall material)
overall: 16.3 cm x 29 cm x 28 cm; 6 13/32 in x 11 13/32 in x 11 1/32 in
ID Number
catalog number
accession number
Credit Line
Gift of Friends Meeting of Washington
See more items in
Medicine and Science: Mathematics
Calculating Machines
Science & Mathematics
Data Source
National Museum of American History
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