Calculating device, called Arithmeticall Jewell

Add to album

This calculating device called the 'Arithmeticall Jewell' permitted addition, subtraction, multiplication and division to be undertaken without use of pen and paper. It was designed by William Pratt in 1616.

The device comprises two ivory faced wooden tablets. One (below in the picture) has 14 columns, each with small brass parallel sectors. The other has seven pairs of columns for laying out 'astronomical fractions' to the base 60.

In England at this time the new form of ciphering with Hindu-Arabic numerals had largely, but only recently, replaced the traditional manual arithmetic done with counters on a counting board, with the results recorded in ledgers in Roman numerals.

Record details

To search on related items, click any underlined text below.

• Online ID: 000-100-102-829-C
• Image Rights Holder: National Museums Scotland
• Project: National Museums Scotland
  Project description   View all records in project
• Ref: National Museums Scotland  T.1985.114
• Date: Around 1616
  c. 1616
  
• Material: Wood, ivory
  Arithmeticall Jewell / perpetual pro-forma / tablet
  
• Dimensions: 122 mm x 65 mm x 5 mm (each tablet)
  
• What: Arithmeticall Jewell / perpetual pro-forma / tablet
  
• Subject:
• Who: William Pratt (Maker)
  
• Where:
• Event:
• Description: Arithmeticall Jewell, consisting of two wooden tablets, perpetual pro-forma for undertaking arithmetic procedures, designed by William Pratt, c. 1616
  
• References:
  • Bryden, D. J., 'The Arithmeticall Jewell or Jewell of Arithmetick' in Quanto: Abbot Hall Art Gallery, Kendall Quarterly Bulletin 23, no 2 (1985), pp 9-14 
• Translations:
• Related Records: