Napier, John

Napier, John, 1550–1617, Scottish mathematician. He invented logarithms and wrote Mirifici logarithmorum canonis descriptio (1614), containing the first logarithmic table and the first use of the word logarithm. His Rabdologiae (1617) gives various methods for abbreviating arithmetical calculations. One method of multiplication uses a system of numbered rods called Napier's rods, or Napier's bones; this was a major improvement on the ancient system of counters then in use. In 1619, after Napier's death, his Mirifici logarithmorum canonis constructio, which gave the method of construction of his logarithms, was published by his son Robert and edited by Henry Briggs. Napier introduced the decimal point in writing numbers. Napier was also known as an outspoken exponent of the Protestant cause. His religious writings include A Plaine Discovery of the Whole Revelation (1593), the earliest Scottish interpretation of the scriptures.

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Napier, John

(born 1550, Merchiston Castle, near Edinburgh, Scot.—died April 4, 1617, Merchiston Castle) Scottish mathematician and champion of Protestantism. He divided his life between attacks on the church of Rome and the pursuit of numerical calculations. On a number of occasions he urged James IV of Scotland to deal firmly with the Catholic threat. From 1594 he worked on developing secret weapons, including a metal chariot with small holes through which shot could be fired. He developed the concept of the logarithm to facilitate calculations involving multiplication, division, roots, and powers. He also introduced the decimal point as a notation for decimal fractions. The set of calculating rods he designed was a precursor to the slide rule.

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Napier, John 

Born 1550 in Merchiston, near Edinburgh; died there Apr. 4, 1617. Scottish mathematician; inventor of logarithms.

Napier studied at the University of Edinburgh. He had mastered the fundamental concepts of logarithms before 1594; however, his Mirifici logarithmorum canonis descriptio . .. (Description of the Marvelous Canon of Logarithms), in which he set forth this knowledge, was published in 1614. This work contained a definition of logarithms; an explanation of their properties; tables of the logarithms of sines, cosines, and tangents; and applications of logarithms to spherical trigonometry. In Mirifici logarithmorum canonis constructio . .. (Construction of the Marvelous Canon of Logarithms), published 1619, Napier set forth the principles for calculating the tables. The kinematic definition of a logarithm given by Napier is essentially equivalent to the definition of a logarithmic function in terms of a differential equation. Napier also discovered a number of formulas for solving spherical triangles that can be conveniently given in logarithmic form.

WORKS

Mirifici logarithmorum canonis descriptio; ejusque usus, in utraque, trigonometria, ut etiam in omni logística mathematica . . . explicatio. Edinburgh, 1614.

REFERENCE

Istoriia matematiki, vol. 2. Moscow, 1970.