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Cranmer Abacus

Cranmer Abacus

Usage conditions apply
This modification of the Japanese abacus or sorobon is designed for use by the blind. It sits in a black plastic box, with red felt in the bottom of the box to prevent the beads from sliding inadvertently. A black plastic cross bar is pierced by 13 parallel metal rods. Each rod has one spherical white plastic bead above the crossbar and four below. Raised dots can be felt on the cross bar and the lower rim of the box at each column, and as raised slashes between every 3 dots. At the top of the front are the raised letters: A.P.H.
This type of abacus was designed by Terence V. (Tim) Cranmer (1925-2001) of the Kentucky Division of Rehabilitation Services for the Blind in early 1962, and soon placed on the market by the American Printing House for the Blind. It is still manufactured today. Cranmer was blind from childhood. He made and sold plastic jewelry in his early years, worked briefly at Kentucky Industries for the Blind, and then spent 10 years as a piano technician. In 1952, he began working for the Kentucky Division of Rehabilitation Services for the Blind, rising through the ranks. He was an active member of the National Federation of the Blind, and made several inventions.
The donor, Russell Kletzing of Sacramento, California, was a lawyer blinded as a child. He 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.
References: Fred L. Gissoni, Using the Cranmer Abacus for the Blind, Louisville, Kentucky: American Printing House for the Blind, 1962.
National Federation of the Blind, "NFB Awards 2000," Braille Monitor, August / September 2000.
Buffe Hanse, "Tim Cranmer Dies," Braille Monitor, January / February 2002.
Deborah Kendrick, “Tim Cranmer: One of Our Great Pioneers,” Access News, vol. 3 #1, January 2002.
Currently not on view
Object Name
date made
ca 1970
place made
United States: Kentucky, Louisville
Physical Description
felt (overall material)
plastic (overall material)
metal (overall material)
overall: 1.2 cm x 15.6 cm x 8.4 cm; 15/32 in x 6 5/32 in x 3 5/16 in
ID Number
catalog number
accession number
Credit Line
Gift of Russell Kletzing and Ruth S. Kletzing
See more items in
Medicine and Science: Mathematics
Learning Arithmetic
Arithmetic Teaching
Science & Mathematics
Data Source
National Museum of American History
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