Contex Adding Machine

Contex Adding Machine

Usage conditions apply
This non-listing adding machine has a gray plastic case and gray and white plastic keys. The ten white numeral keys are on the top right, with the zero bar three times as long as the others. To the left of the numeral keys are four function keys marked C, X, Div, and -. A red plastic place marker is controlled by two keys beneath it. The large actuating bar is on the right. Results appear in 11 windows at the front of the machine. Numbers up to ten digits long can be entered. A twelfth window, to the right of the others, shows the number of times the actuating bar has been pressed. Instructions for operating the machine are given on a sticker attached to the bottom. The four plastic feet are rubber-covered.
The machine is marked on the front and on back: BDC CONTEX. It has serial number on a paper tag attached to the back: 516272. It is marked on the back: BOHN DUPLICATOR CORP. (/) New York 16, New York, U.S.A. (/) MADE IN DENMARK (/) PATENTS PENDING. Bohn would later distribute electronic calculators.
Given to donor Michael Sherman by a friend, Jack Schuss, but never used by donor.
Accession file.
Currently not on view
Object Name
adding machine
date made
ca 1965
Bohn Duplicator Corporation
place made
place distributed
United States: New York, New York City
Physical Description
plastic (overall material)
paper (overall material)
rubber (overall material)
overall: 11 cm x 21 cm x 26 cm; 4 11/32 in x 8 9/32 in x 10 1/4 in
ID Number
accession number
catalog number
Credit Line
Gift of Michael Sherman
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Adding Machines
Data Source
National Museum of American History
Nominate this object for photography.   

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.


I also have one of these. It was my mother's who recently passed. I remember her using it to pay the monthly bills.

Add a comment about this object