John Napier

John Napier’s first marriage was in 1572 to Elizabeth, daughter of James Stirling, the 4th Laird of Keir and of Cadder. The couple had two children. Elizabeth died in 1579.

He then married Agnes Chisholm with whom he had ten more children.

He died on 4 April 1617, in Edinburgh, Scotland.

John Napier was born on 1 February 1550, in Merchiston Tower, Edinburgh, Scotland. His father, Sir Archibald Napier of Merchiston Castle was a wealthy landowner and his mother, Janet Bothwell, was a daughter of the politician and judge Francis Bothwell, Lord of Session.

His Latinized name was Joannes Neper and he was also known as Jhone Neper.

As was customary for young boys of his social stature, he received his early education at home from private tutors. He was sent to St Salvator's College, St Andrews, for his formal education when he was 13.

He developed an interest in theology while at the college and the love for the religion dominated his life till the very end. But, he did not study at the college for long and appears to have left before earning his degree.

Not much is known about how he acquired his training in mathematics. It is believed that young John travelled to Mainland Europe for his further education at the advice of his maternal uncle. It is likely that he studied at the University of Paris and it is also probable that he spent some time in Italy and the Netherlands.

After completing his studies he returned to Scotland in 1571, at the age of 21. Now that he was a young man, most of the estates of the Napier family were transferred to him in 1572.

He also bought a castle in Gartness in 1574. He soon engaged himself in managing the estates. During this time he also got married and began raising a growing family.

In addition to managing his estates, he became involved in mathematical research during his leisure time. He was also an ardent Protestant and was actively involved in the religious controversies of the time which sometimes hindered his scientific pursuits.

In 1594, he published ‘Plaine Discovery of the Whole Revelation of Saint John’, a religious work written with the intent of influencing contemporary political events. The text holds a prominent place in Scottish ecclesiastical history.

His father died in 1608 and John Napier moved to Merchiston Castle in Edinburgh with his family and resided there for the remainder of his life.

John Napier is regarded as the founder of what is now known as Napierian logarithm or Naperian logarithm. The term is often used to mean the natural logarithm. His invention of logarithms paved the way for much further advancement in not just mathematics, but also in astronomy, dynamics, and other areas of physics.

He developed the manually-operated calculating device which came to be known as Napier's bones. The device could be used for calculation of products and quotients of numbers. The method was based on a combination of techniques used in Arab mathematics and the lattice multiplication.