Tabulat with numbering rods

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This wooden frame, or tabulat, was used to hold numbering rods known as Napier's bones. The bones were invented by the Scot John Napier (1550-1617). They were used to convert multiplication and division into simpler problems of addition and subtraction.

In this photograph the tabulat holds three bones. Each bone has four sides, each with a multiplication table on it. On the left of the tabulat is a fixed multiplier rod.

The tabulat was invented after Napier's death. Its use is first recorded in 1648 by a London mathematician, but it probably dates earlier than this. Using the tabulat it was easier to line up the bones and to ready off the results.

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• Online ID: 000-180-000-742-C
• Image Rights Holder: National Museums Scotland
• Project: National Museums Scotland Part 2
  Project description   View all records in project
• Ref: National Museums Scotland  
• Date: Probably 18th century
  
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