Formed by polymerization of cyanic acid (gaseous or liquid). Prepd by digesting equal parts of potassium cyanate and oxalic acid: Liebig, W"ohler, Berzelius Jahresber. 11, 85. Crude cyamelide contains cyanuric acid which is removed by washing with water: Senier, Walsh, J. Chem. Soc. 81, 290 (1902). Mechanism of polymerization: Werner, Fearon, ibid. 117, 1358 (1920).