Burroughs Duplex Subtractor

This black full-keyboard printing adding machine has 13 columns of black and white round plastic keys above an unpainted steel keyboard. On the right of the number keys are a variety of function keys. One column of these refers to register 1, the other to register 2. In back of the keyboard is a wide carriage, with a place for a paper tape. On the top are two sliding steel markers, one missing a piece. No cord or handle.
A red paper tag attached to the machine reads: PATENT DEPT. (/) #176. A metal tag with the object reads: B.A.M.CO. (/) MODEL (/) NO 1020. The machine is marked on the front: Burroughs. The mark has a hook over the “g” in Burroughs. A paper sheet received with the machine reads: Do not depress Register #1 motor (/) bars while operating machine as Register (/) wheels do not shift properly and machine (/) will lock on half cycle. A metal tag attached to the object reads: DONATED TO (/) The Smithsonian Institution (/) by (/) Burroughs Corporation.
The machine is associated with Burroughs inventor Ernst Racz. It was model #176 in the collection of the Patent Division of Burroughs Corporation.
Currently not on view
Object Name
adding machine
date made
ca 1940
Burroughs Adding Machine Company
Physical Description
plastic (overall material)
paper (overall material)
metal (overall material)
overall: 27.6 cm x 49 cm x 38.5 cm; 10 7/8 in x 19 9/32 in x 15 5/32 in
place made
United States: Michigan, Detroit
ID Number
catalog number
accession number
Science & Mathematics
Adding Machines
See more items in
Medicine and Science: Mathematics
Adding Machines
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Burroughs Corporation
Additional Media

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.