The development of problems within the phlogiston theories, 1766-1791

This is the first of a pair of papers. It focuses on the development of the most notable phlogistic theories during the period 1766-1791, including the main experiments that they attempted to interpret. There was a rapid proliferation of late phlogistic theories, particularly from 1784, and the compositional features and implications of the main theories are set out and their issues analysed. Each of the main phlogistic theories either reached impasses due to internal problems, or included features which made them unacceptable even to other phlogistians. The expositions and analyses of these theories are given in terms of details that were in the literature at the time or otherwise potentially understandable by the participants given current practices. Some relevant methodological aspects of the history of science are discussed, and the secondary literature is briefly surveyed.