This important work on seventeenth-century anatomy and medicine offers a rich and varied account of one of the well-known centers of early modern anatomy, namely the University of Leiden and its Theatrum anatomicum. The novel information unearthed in Huisman's study is somewhat surprising, since Leiden is far from overlooked in existing accounts of the history of anatomy. Many earlier standard studies include engravings of the anatomical theater of Leiden, and chapters on its famous professors Petrus Paaw and Goverd Bidloo. Huisman's thorough chronological account is nonetheless full of newly accumulated knowledge about the Leiden theater, from its creation in the late sixteenth century until its gradual demise in the early 1700s.

The foundation of the Theatrum anatomicum in 1594, under the direction of Petrus Paaw, coincided with the establishment of Fabricius ab Aquapendente's extant anatomy theater at the University of Padua. This was hardly coincidental; like other prominent anatomists of the late Renaissance, Paaw was originally educated in Padua. The joint establishment of an anatomical theater and a botanical garden in Leiden was another imitation of similar facilities at the University of Padua. The early history of anatomical practice in Leiden was furthermore linked to Paduan humanist culture in its allegorical view of nature and classical antiquity. In the anatomical theater of Leiden contemplations on life and mortality were emphasized by mounted human frames bearing banners with Latin inscriptions asserting the fragility of man and brevity of life. Contemporary engravings of the theater show a rectangular dissection table surrounded by circular rows of wooden benches, and mounted skeletons of humans and animals. At this early stage activities within the theater were still concentrated on public demonstrations of anatomy taught through dissection. Under Paaw's unlikely successor Otho Heurnius, however, this priority changed significantly, and the Theatrum anatomicum developed into one of the most well-known Kunst- and Wunderkammern of Northern Europe after his appointment in 1618. Heurnius seems to have had little interest in dissection, and instead spent most of his thirty years as the chair of anatomy in the establishment of a renowned collection of naturalia and artificialia within the theater precincts. Among the rarities collected by Heurnius was a large Egyptian stone sarcophagus, later referred to as the “groote mumie” (“large mummy”), which became one of the highlights of the collections within the Theatrum anatomicum. Under Heurnius's professorship the teaching of anatomy was instead left to his assistant Adrianus Volckenburg.

The collecting activity of Heurnius was not continued by his successor Joannes van Horne, whose only addition was the acquisition of a rich collection of anatomical preparations produced by his colleague Louis de Bils. Under Horne, the study and teaching of anatomy and physiology once again became the central occupation within the Leiden anatomy theater. Several of the most renowned anatomists of the seventeenth century (including Frederik Ruysch, Jan Swannerdam, and Nicolaus Steno) were students of van Horne, and their joint research and discoveries opened new chapters in the study of anatomy and physiology, helped along by systematic use of the microscope. The practice of descriptive anatomy taught for large audiences became secondary to new small-scale studies carried out elsewhere in more private settings. Besides microscopes these studies included regular usage of syringes applied for the injection of hot wax into veins and organs of humans and animals. Numerous vivisections were carried out on dogs, rabbits, and frogs, and vividly documented by the Danish polymath Ole Borch, who visited the University in the early 1660s. The objective of tracing “the finger of God” in the investigation of his most refined creation was continued during this period of still more subtle anatomy studies. Prior allegorical interpretations of nature presented in a public theatrical setting by banner-carrying skeletons, were replaced with more private and professional contemplations of the divine creation and its remarkable workings.

Huisman's The Finger of God presents a rich account of the often conflicting activities of anatomy and antiquarianism within the Leiden anatomy theater. Curiously, the “anatomy servants” originally appointed to assist in the dissections increasingly became custodians of the collections of the Theatrum anatomicum. At the turn of the seventeenth century the latter activity proved much more profitable, and these assistants had catalogues of the collections printed at their own expense, which were sold to theater visitors. The development of the Theatrum anatomicum from a center of anatomical research and demonstration, and towards a museum of curiosities continued until its demise in the early nineteenth century, and is vividly described in Huisman's fine book.