In 1795 Barker read Lavoisier’s chemistry, experimented on tainted meat made edible by soaking in alkalis, and began using alkaline therapy such a limewater. He wrote about this to Samuel Mitchill and Benjamin Rush, telling them that he had been called a “dangerous innovator.” A brief history of the acid/alkali debates of the seventeenth and eighteenth centuries includes information about Otto Tachenius, John Colbatch, Hermann Boerhaave, George Ernst Stahl, William Cullen, Joseph Black, and Antoine Lavoisier. Barker wrote about his experiments, azotic air (nitrogen), and his difficulty understanding the mechanism of this apparently successful therapy. His results were published in the Medical Repository, beginning a correspondence with Samuel Latham Mitchill, professor of chemistry at Columbia University. Contributors to the discussion of alkalis included David Hosack, Thomas Beddoes and James Watt, Humphry Davy, and Matthew Carey. Comments by Charles Rosenberg, John Harley Warner, Lester King, and others help us make sense of medical science and the acid/alkali battle.