This description of processes of burning was much more in keeping with the ideas of the time than that given by Boyle, Rey and Mayow.

It was adopted by Stahl, and made the basis of a general theory of those changes wherein one substance disappears and another, or others, very unlike it, are produced.
That he might bring into one point of view, and compare the various changes effected by the agency of fire, Stahl invented a new Principle, which he named _Phlogiston_, and constructed an hypothesis which is generally known as the phlogistic theory.

He explained, and applied, this hypothesis in various books, especially in one published at Halle in 1717.
Stahl observed that many substances which differed much from one another in various respects were alike in one respect; they were all combustible.

All the combustible substances, he argued, must contain a common principle; he named this supposed principle, _phlogiston_ (from the Greek word _phlogistos_ = burnt, or set on fire).

Stahl said that the phlogiston of a combustible thing escapes as the substance burns, and, becoming apparent to the senses, is named fire or flame.