Monroe Model 8N-213 Calculating Machine

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.

Date Made: 1960

Maker: Monroe Calculating Machine Company, Inc.

Location: Currently not on view

Place Made: United States: New Jersey, Orange

Subject: Mathematics

Subject:

See more items in: Medicine and Science: Mathematics, Calculating Machines, Science & Mathematics

Exhibition:

Exhibition Location:

Credit Line: Gift of University of Pittsburgh

Data Source: National Museum of American History

Id Number: 1980.0255.01Catalog Number: 1980.0255.01Maker Number: B973812BAccession Number: 1980.0255

Object Name: calculating machine

Physical Description: rubber (overall material)plastic (overall material)steel (overall material)Measurements: overall: 20.5 cm x 37 cm x 34.2 cm; 8 1/16 in x 14 9/16 in x 13 15/32 in

Guid: http://n2t.net/ark:/65665/ng49ca746a5-1d00-704b-e053-15f76fa0b4fa

Record Id: nmah_690566

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