Roger Bacon ((1210 to 1215?)-1294) was an English Alchemist and Philosopher during the Middle Ages who insisted on conducting his own experiments and observing the results, as opposed to depending upon the writings of others.
Hans Nintzel selected these four works for inclusion in the R.A.M.S. Library:
    Radix Mundi
    The Mirrour of Alchimy
    The Oil of Antimony
    Miracles of Art, Nature and Magick

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Roger Bacon an Englishman, a founded Scholar of Merton-College in Oxford, a very quick Philosopher, and withal a very famous Divine, he had an incredible knowledge in the Mathematicks, but without Necromancy (as John Balleus doth report) although he be defamed for it by many: Now this man after he had sharply reproved the times wherein he liv’d; these Errours, saith he, speak Antichrist present. Nicholas the Fourth Pope of Rome did condemn his Doctrine in many things, and he was by him kept in prison for many years together; as Antonine hath it in his Chronicle. He flourished in the year of our Lord, 1270.