"Boyle was one of the most active experimenters, and certainly the greatest chemist of his age. He introduced the use of tests or s, active substances for detecting the presence of other bodies: he overturned the [prevalent] ideas... that the results of operations by fire were the real elements of things, and he ascertained... important facts respecting inflammable bodies, s, es, and the phænomena of combination; but neither he nor any of his contemporaries endeavoured to account for the changes of bodies by any fixed principles."