# John Thing

John Machin (1680 - 1751) is known mainly to have calculated in 1706 100 decimals of pi thanks to the formula which bears its name, the Formule of Thing:

$\ frac \left\{\ pi\right\} \left\{4\right\} = 4 \ arctan \ frac \left\{1\right\} \left\{5\right\} - \ arctan \ frac \left\{1\right\} \left\{239\right\}$

## Biography

John Machin taught mathematics with Brook Taylor in 1701, two years before Taylor enters to the St John' S College (Cambridge). He continued to correspond with him during several years.

John was friendly with Keill, which taught in Oxford, and with De Moivre which was like Machin, a private teacher of mathematics in this time.

The May 16th 1713, Machin was named as Professor of Astronomie to the Gresham College with London. It succeeded Dr. Torriano and continued to hold the pulpit until its death later 38 years.

John Machin was used as secretary of the Royal Society of 1718 for 1747. He also formed part of the commission which decided prioriété of Calculation between Leibniz and Newton in 1712.

With regard to the Formula of Thing established in 1706, the interested parties will be able to make use of the properties of the function arctan and to also note that 120*239-119=119*239+120 to try redémontrer

## Works

• The Laws off the Moon' S Motion According to Gravity (1729)
• The solution off Kepler 'S problem (1738)
• Squaring off the Circle (1758)

## External bond

 Random links: Historia del santo San Cristobal y Nieves | Pierre abbot | Claude-Victor Perrin | Consejo de ciudad de Castlereagh | Monique Barbut | Marian Čišovský | Carl Storck | Morganton,_la_Géorgie