The Abacus: Index

Introduction Construction · Basics · Java Applet · Technique · The Abacus Today
History Timeline · Salamis Tablet · Counting Board · Roman Hand Abacus · Suan Pan · Soroban · Schoty · Nepohualtzitzin · Khipu · Lee Abacus
Interactive Abacus Tutor Sarat Chandran and David A. Bagley's incredible Java abacus with a built-in tutor for counting, addition and subtraction.
Calculations Addition · Subtraction · Multiplication & Division · Square Roots · Cube Roots
The Lee Abacus The manual for the Lee Abacus, c. 1958 is available as Text
The Abacus as Art Michael Mode builds exotic abaci as art objects.
Abacus: Mystery of the Bead Abacus Techniques by Totton Heffelfinger & Gary Flom.

Articles, Excerpts and Analysis

The Abacus vs.The Electric Calculator In 1946, a contest held in Tokyo, pitted an abacus against an electric calculator; the abacus won, of course.
Feynman vs. The Abacus Richard Feynman battles against the abacus; the result is not surprising (if you know Feynman).
Comparing the Chinese and the Mesoamerican Abacus An analysis contributed by David B. Kelley.
The Roman Hand-Abacus An analysis contributed by Steve Stephenson.
Ancient Computers Steve Stephenson contributes another analysis on the Salamis Tablet and the Roman Hand-Abacus and proposes a theory on how these devices evolved.
Using a Counting Board In this video, Steve Stephenson explains how to use a Counting Board like the Salamis Tablet.
The Incan Khipu String, and Knot, Theory of Inca Writing by John Noble Wilford. Talking Knots of the Incas by Viviano and Davide Domenici.
Lost Tribes, Lost Knowledge An article about the dangers of forgetting knowledge learned from the past, by Eugene Linden.

All Things Abacus

Additional Abacus Resources Purchase or build an abacus · An abacus for your Palm · Books about the abacus · Java applet source code · The Mesoamerican abacus
Resources For Teachers The abacus in the classroom · Abacus lesson plan · Math and science resources for teachers
Photos High-resolution photos of my abacus collection.

What's New

NOTE: The webserver hosting this site will be offline on Dec. 28-29, 2011 for scheduled building electrical systems maintenance.

Updated: Thu 08 Dec 2011 03:41:03 PM EST

Frequently Asked Questions

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Awards & Honours

In existence since 1995, this site has collected a few awards and the Java applet appeared in several books and magazines.

Thanks

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Contents

Introduction

History

Interactive Abacus Tutor

Calculations

The Lee Abacus

The Abacus as Art

Abacus: Mystery of the Bead

Articles, Excerpts and Analysis

The Abacus vs.The Electric Calculator

Feynman vs. The Abacus

Comparing the Chinese and the Mesoamerican Abacus

The Roman Hand-Abacus

Ancient Computers

Using a Counting Board

The Incan Khipu

Lost Tribes, Lost Knowledge

All Things Abacus

Additional Abacus Resources

Resources For Teachers

Photos