All the anatomical plates that illustrate this medical treatise are grouped together (anarchic chronology) at the end of the book. Each plates contains one or more figures that are accompanied by Roman letters. These refer to textual descriptions which in the case of this print are found on pages 166-168 of the treaty (1 Fig.). For this engraving it is specified that Dom Vernay to carry out the medical operation which allowed to remove the veins from the base of the brain in order to see the origin of the nerves : "Dom Vernay exhibet basin cerebri Humani, liberatam ab omnibus vasis sanguiferis, ad ostendendam originem decem parium nervorum, qui e medulla oblongata proveniunt(...)"
