In medieval and early modern Europe, the practice of alchemy promised extraordinary physical transformations. Who would not be amazed to see base metals turned into silver and gold, hard iron into soft water, and deadly poison into elixirs that could heal the human body? To defend such claims, alchemists turned to the past: scouring ancient books for evidence of a lost alchemical heritage--and seeking to translate their secret language and obscure imagery into replicable, practical effects. Tracing the development of alchemy in England over four hundred years, from the beginning of the fourteenth century to the end of the seventeenth, Jennifer M. Rampling illuminates the role of alchemical reading and experimental practice in the broader context of national and scientific history. Using new manuscript sources, she shows how Roger Bacon, George Ripley, John Dee, Edward Kelley, and Isaac Newton, as well as many previously unknown alchemists, devised new practical approaches to alchemy, while seeking the support of English monarchs, including Henry VIII and Elizabeth I. By reconstructing their alchemical ideas, practices, and disputes, Rampling reveals how English alchemy was continually reinvented over the space of four centuries, resulting in changes to the science itself. In so doing, The Experimental Fire bridges the intellectual history of chemistry and the wider worlds of early modern patronage, medicine, and science.