[An] impressive book. Newman has pulled off two remarkable achievements in a single book--and one of modest size at that. To begin with, he has reconstructed the career of an intellectual adventurer whose talents for investigating the natural world and for promoting his own fame were equally outsized. [Starkey] was not only a medical reformer, he was also one of the most ingenious and prolific of those strange figures, half con man and half high-tech entrepreneur, who were known at the time as projectors. This story of a forgotten career, though told with much learning and occasional wit, forms only one strand in the double helix of Newman's book. He also seeks to identify the sources and explain the contents of Starkey's chemical thought and practice. The obstacles to such a project that the historian of alchemy confronts would daunt most scholars. By painstaking and meticulous analysis [Newman] establishes the exact chemical experiments that Starkey had devised, identifying their ingredients in both seventeenth-century and modern terms.

The dark language of alchemy emerges as an early form of scientific notation: precise, rigorous, inaccessible to the outsider but clear to the expert. Considered simply as a piece of historical craftsmanship, Newman's efficient decoding and partial rehabilitation of these rebarbative texts compels admiration. Gehennical Fire deserves to reach a wide public. It helps to revise a revisionist historiography of science which has become something of an orthodoxy in its own right. The boundaries between Aristotelianism and alchemy, establishment science and reform, traditional natural philosophy and the Scientific Revolution emerge from his analysis as permeable, even fluid: territories long described as separate turn out to overlap. Above all, Newman offers powerful evidence that the dark science of alchemy formed part of the high intellectual tradition in medieval and Renaissance Europe. Neither the alchemists' alembics not their lives will ever look quite the same.