History of the metric system levels of the krypton 86 atom as the new standard for the metre. The standard metre artefact was retired. In 1960, Giorgi's proposals were adopted as the basis of the "Système International d'Unités" (International System of Units), the SI. This initial definition of the SI included six base units, the metre, kilogram, second, ampere, degree Kelvin and candela, and sixteen coherent derived units. The evolution of the SI after its publication in 1960 has seen the addition of a seventh base unit, the "mole", and six more derived units, the "pascal" for pressure, the "gray", "sievert" and "becquerel" for radiation,
Si Prat are found in "Khamhaikan Khun Luang Ha Wat" and "Khamhaikan Chao Krung Kao", documents derived from an original Mon chronicle compiled from the testimony of Siamese captives following the fall of Ayutthaya in 1767. These documents focus on his banishment and death, but state that they happened during the reign of King Suriyenthrathibodi, several decades later than Narai. The detailed biography which gives explicit years for Si Prat's birth and death and places his lifetime during Narai's reign was written by Phraya Pariyattithammathada (Phae Talalak) and published as "Tamnan Si Prat" ("The Legend of Si Prat") in 1919. The work,