What’s That Measurement Tool? The World’s Oldest Computational Device

Next time you crank up Excel to crunch some data, consider the earliest known computational tool, the Ishango Bone. This 10 cm-long section of the fibula (outer calf bone) of a baboon now resides in the Royal Belgian Institute of Natural Sciences in Brussels. That’s it up above, with a pair of views below.

It was discovered in 1960 near Lake Edward, on the border between Uganda and today’s Democratic Republic of Congo, during the excavation of an ancient settlement that was buried in a volcanic eruption. It’s 20,000 years old, more or less, from about the time of the height of the last Ice Age.

The Ishango Bone has a sharp piece of quartz affixed to one end, apparently for use as a marking or notching tool. (Perhaps it’s also the first known pencil?) Most importantly, it has three columns of notches running down its length, represented here:

Ishango Bone Left Column

Ishango Bone Left Column


Ishango Bone Center Column

Ishango Bone Center Column


Ishango Bone Right Column


The notches are organized in a way that implies that this artifact is much more than the world’s oldest data storage device. Scholars have put forth various interpretations of the purpose of the notches. What do you think it was used for? A tally of goods? A number system? A procedure for multiplication or division? A very early tax return?

Let us know what you think. Write us directly, or leave your thoughts in the comments below.

About Author

Bill Paarlberg

Bill Paarlberg is the Editor of The Measurement Advisor. He has been editing and writing about measurement for over 20 years. He was the development and copy editor for "Measuring the Networked Nonprofit" by Beth Kanter and Katie Paine, winner of the 2013 Terry McAdam Book Award.