ABSTRACT
Secrets conjures up mysterious, perhaps marvelous knowledge, and many books of secrets gesture towards marvels and wonders or allude to the esoteric nature of their contents. In early modern Europe, craft secrets were to a large degree tacit and ineffable. They involved techniques and practices that were often too complicated to be written down but instead could only be learned by observing, attending, imitating. Recipes for softening hard substances and hardening soft substances or the related process of fixing volatile materials are to be found in overwhelmingly large numbers in such collections. Books of secrets often indiscriminately mix medical recipes for human health with instructions for pigment, dye and metallurgical recipes. Recipe collections, then, could encourage an attentive meditation on materials; they could develop a habit of regarding matter and its manipulation. Such a grounding in the habits of practice and the behavior of matter led to an ability to intuit, improvise and innovate.
