This paper investigates the emergence, in the second part of the 17th century, of a new body of experimental knowledge dealing with the chemical transformations of water taking place in plants. We call this body of experimental knowledge a “chemical history of vegetation.” We show that this chemical natural history originated, in terms of recipes and methods of investigation, in the works of Francis Bacon and that it was constructed in accordance with Bacon's precepts for putting together natural and experimental (...) histories. Our paper covers a wide array of experimental investigations, carried out by people with different backgrounds, theoretical assumptions, and metaphysical allegiances (Thomas Browne, Robert Sharrock, Robert Boyle, Nehemiah Grew, John Beale, and John Evelyn). We claim that, despite their differences, these naturalists had a lot in common. First, they treated plants as laboratories of chemical investigation. Second, they used the experiments with plants to develop tools, hypotheses, and operational concepts, which travelled from one naturalist to the other, even when their respective explanatory vocabularies were widely different. Third, we show that some of them also manifested an interest in defining and clarifying the limits and structure of this new body of experimental knowledge, displaying, thus, a certain disciplinary unity. (shrink)