Seventeenth-century experimenta , magisterial formulae and the ‘animal alkahest ’: new documents found in Royal Society archives

In this paper we present three newly rediscovered documents from the Royal Society archives that, together with the four described in our previous publications, constitute a set on a cognate theme. The documents were written by, or addressed to, members of the early Royal Society, and their subject is several magisterial formulae, including J. B. van Helmont's alkahest and Ludus. In addition to the interest in those formulae as medicines for various grave illnesses, our analysis showed that some seventeenth-century scholars sought to explain operations of the animal body by invoking similar but natural substances, while attempting to assimilate the latest anatomical discoveries into a novel framework. The complete set of documents sheds some new light on the interests of seventeenth-century networks of scholars concerned with experimenta.