It [air] was liable, according to the phlogistians, to vitiation, by the addition to it of phlogiston, […]1810, George Wilson, “General Sketch of Cavendish's Scientific Researches and Discoveries”, in The Life of the Honᵇˡᵉ Henry Cavendish, page 39:
Bryan Higgins was a "phlogistian", while William, correctly as it turned out, didn't believe in the concept.2007, Charles Mollan, “William Higgins (1763-1825)”, in It's Part of What We Are (Science and Irish Culture; 3), volume 1, Dublin: Royal Dublin Society, →ISBN, page 236:
phlogistian
adj
Etymology From phlogist(on) + -ian.
1
Of or pertaining to phlogiston or phlogiston theory.
In Davy's time it was still necessary in considering any novel fact to keep the phlogistian hypothesis in view, and to demonstrate its inability to explain the new discoveries.1894 July 13, “Notices of Books”, in William Crookes, editor, The Chemical News and Journal of Physical Science, volume 70, number 1807: