The relation between alchemy and early chemistry is still open to debate. How did what is now often dismissed as a pseudo-science contribute to the emerging science of chemistry, a subject that by the late eighteenth century, was often held up as a model for other sciences? Alchemy may have bequeathed to chemistry some processes and apparatus; more fundamental, however, was a transformation in mentality. It was in the seventeenth century that much of this transformation took place.

A study that was deeply anthropomorphic, making constant use of allegories and symbolism, and with a language rejoicing in mystery and concealment, gradually became depersonalized, much more objective, and more open. Poetic descriptions, a moral dimension, and a hierarchical view of matter all disappeared. Practical considerations required a concern for greater purity of materials, necessary for the successful replication of experiments. A study of the series of seventeenth-century French textbooks of chemistry from Beguin to Lemery reveals a growing desire for practical results and plain speaking. Robert Boyle was particularly influential in urging the necessity of plain language. The creation of a suitable language to denote and differentiate among different chemical species was a crucial step in the development of early chemistry, thus preparing the way for the systematic names introduced in the following century and the full organization of the science on rational lines.

Both “early chemistry” and “modern concepts” are imprecise. The earliest references to the materials involved in metallurgy, painting, ceramics, and the like, reveal an awareness that one group of materials were called “salts” because of their similarities. I consider this a chemical “concept.” Seeking another example I claim to have found it in the so-called “mineral acids.” The evidence for the existence of this concept is cumulative during the period just before the emergence of “modern chemistry,” of which it may be considered a cause. That evidence is particularly found in the literature of pharmacy and of medicine, both of which belong to the practical arts.

The overall portrayal of early modern experimentation as a new method of securing assent within a philosophical discourse sketched in many of the recent studies on the historical origin of experimentation is questioned by the analysis of the experimental practice of chemistry at the Paris Academy. Chemical experimentation at the Paris Academy in the late seventeenth and early eighteenth century originated in a different tradition than the philosophical. It continued and developed the material culture of the chemical work shops of the sixteenth and seventeenth centuries, and explored epistemic objects which had rather loose connections to philosophy. On the other hand, I argue against the classical dichotomy between the work of the mind that of the hand, and for an epistemology of experimentation that acknowledges that experimental manipulation goes hand in hand with reflexion. In particuler, I argue against the view that chemists at the Paris Academy were “pragmatists” who merely gathered experimental facts and classified substances and operations without perplexing themselves over general conceptions. I claim that the chemists at the Paris Academy constructed a general conception framework which shaped the significance of their experiments. This conception that I call conception of the chemical combination, compound and reaction was rather quickly reified into an experimental fact. Despite its generality it was a genuine chemical conception rather independent of philosophy.

Etienn-François Geoffroy' Table des Rapports is generally regarded as a landmark in the evolution of chemistry during the eighteenth century. Issues have arisen among historians concerning the significance and originality of the Table that require fuller attention to the immediate context of chemical research in the Academie des sciences during the two decades that preceded its appearance. The present paper argues that, despite the transition from communal to individual research projects that marked the reorganization of the Academy in 1699, chemists continued to pursue shared problems within a communal ethos. The interactions between Wilhelm Homberg, Etienne-François Geoffroy, and Louis Lemery were particularly prominent. The paper traces one example of this interaction, involving the sulfur principle and its influence on one entry in Geoffroy's Table. Further such studies are needed to elucidate the relation between the concepts of chemical composition and reactions implied in Geoffroy's table and the concepts embodied in the previous work of Geoffroy and his associates in the Academy.

In chemistry one observes different relationships [rapports] between different bodies, which act such that they unite easily with one another. These relationships have their degrees and their laws. One observes their different insofar as, among several materials are confounded and that have some disposition to unite together, one perceives that one of these substances always unites constantly with a certain other [substance] preferably to all others.