Environmental radioactivity g) to that of the soil water (Bq ml). If the radioactivity is tightly bonded to by the minerals in the soil then less radioactivity can be absorbed by crops and grass growing in the soil. One dramatic source of man-made radioactivity is a nuclear weapons test. The glassy trinitite formed by the first atom bomb contains radioisotopes formed by neutron activation and nuclear fission. In addition some natural radioisotopes are present. A recent paper reports the levels of long-lived radioisotopes in the trinitite. The trinitite was formed from feldspar and quartz which were melted by the heat. Two samples
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,