What is "sendivogius"

Michał Sędziwój (also Michael Sendivogius, Sędzimir or simply Sendivogius; 1566–1636) of Ostoja coat of arms, was a Polish alchemist, philosopher, and medical doctor. A pioneer of chemistry, he developed ways of purification and creation of various acids, metals and other chemical compounds. He discovered that air is not a single substance and contains a life-giving substance-later called oxygen 170 years before similar discoveries by Scheele and Priestley. He correctly identified this 'food of life' with the gas (also oxygen) given off by heating nitre ( saltpetre). This substance, the 'central nitre', had a central position in Sendivogius' schema of the universe.