John Napier

John Napier of Merchiston, known as Marvellous Merchiston, was a Scottish landowner who lived from 1550 to 1617. He was a mathematician, physicist, and astronomer.

He is famous for discovering logarithms, which made hard calculations much simpler.

Napier also invented an early tool for calculating called Napier's bones. He helped make the decimal point popular in math. He was the 8th Laird of Merchiston, meaning he owned a big estate.

His birthplace, Merchiston Tower in Edinburgh, is now part of Edinburgh Napier University. You can see a memorial for him at St Cuthbert's Parish Church in Princes Street Gardens in Edinburgh.

Life

John Napier was born in 1550 in Scotland. His father was very young when John was born. John studied in Europe and learned Greek, which was unusual.

In 1571, John returned to Scotland. He bought a castle and later moved into Merchiston Castle after his father passed away. John made clever inventions to help with math, including tools called Napier's bones. He also wrote about ways to defend ships. John passed away in 1617 from an illness called gout.

Mathematics

John Napier helped a lot with mathematics. He created something called logarithms, which made hard math much simpler. In 1614, he wrote a book with tables of these logarithms. He also talked about special math rules for shapes on a sphere.

Napier also made numbers easier to use with decimals. He even made a tool called Napier's bones to help with multiplying numbers. He worked with other famous scientists and shared his ideas about logarithms. His work helped make many new discoveries in science, like learning about stars and how things move.

Theology

John Napier was very interested in the Book of Revelation. He believed the Pope was the Antichrist and wrote about this.

Napier thought his book A Plaine Discovery of the Whole Revelation of St. John was very important. He wrote it so many people could read it. In this book, Napier used math to study the Book of Revelation. He believed big events might happen in the future. He thought the end of the world might come in 1688 or 1700, but he said no one really knows the exact date.

Napier dedicated this book to James VI. The book was popular and was translated into other languages.

Interest in the occult

John Napier was also interested in things that seemed magical to people. Some stories say he tried alchemy and necromancy. A few people even thought he had a special animal helper called a familiar spirit.

His neighbors sometimes thought he was doing magic, especially after a few strange events. For example, Napier had a black chicken that he used in a clever way to find a thief. He told his servants to touch the chicken in a dark room, but he had secretly covered the chicken with soot. When they came out, he checked their hands to see who was too scared to touch the chicken.

Napier also used clever tricks with animals. Once, he wanted to stop pigeons from eating his grain, so he spread grain mixed with alcohol in a field. The pigeons got too drunk to fly, and he could easily catch them.

There is also a story about Napier agreeing to look for hidden treasure at Fast Castle with Robert Logan of Restalrig, but he never found any treasure there.

Influence

John Napier had many followers who used his ideas. Two of them were instrument makers named Edmund Gunter and John Speidell. Napier's discovery of logarithms helped people use decimal arithmetic more easily. Another writer, Thomas Urquhart, used Napier's work in his book.

A mathematician named Henry Briggs also liked Napier's logarithms. He made a new table of logarithms using base 10.

Eponyms

Many things are named after John Napier. In electrical engineering, a unit called the neper is used, and it is named after him. There is also a university in Edinburgh, Scotland, called Edinburgh Napier University, named in his honor.

The Moon even has a crater named after him, called Neper. In several languages, the natural logarithm and the mathematical constant e are named after him.

Family

In 1572, John Napier married a girl named Elizabeth, who was only 16. She was the daughter of James Stirling, the Laird of Keir and Cadder. They had two children together, but Elizabeth passed away in 1579. Napier married again to Agnes Chisholm, and they had ten more children.

Napier's father-in-law, Sir James Chisholm, was part of a plan that led to him being banned by some church leaders. Napier was in that group and asked the king, James VI and I, to make sure the punishment happened, but the king chose a calmer way. Napier also had a half-brother named Alexander Napier, who was called Lord Laurieston.

List of works

John Napier wrote several important books. In 1593, he wrote A Plaine Discovery of the Whole Revelation of St. John. In 1614, he published Mirifici logarithmorum canonis descriptio. An English translation by Edward Wright came out in 1616. After he died in 1617, his book Rabdologiæ seu Numerationis per Virgulas libri duo was released. Another book, Mirifici logarithmorum canonis constructio, was written earlier but published later by his son Robert in 1619. Much later, in 1839, De arte logistica was published.