architect who is credited with the invention of Greek fire, a highly incendiary liquid that was projected from “siphons” to enemy ships or troops and was almost impossible to extinguish.

Born in Syria, Callinicus was a Jewish refugee who was forced to flee the Arabs to Constantinople. The ingredients of Greek fire were kept a state secret, known only by the Byzantine emperor and Callinicus' family, which manufactured it. The precise composition is still unknown, but it is generally accepted that it was a mixture of naphtha, pitch, sulfur, possibly saltpetre, and some unknown ingredients. First used in the Battle of Cyzicus (c. AD 673) by the Byzantines against a Saracen fleet off Constantinople, Greek fire proved to be instrumental in that Byzantine victory.