Translations:Manfred Klett: Von der Agrartechnologie zur Landbaukunst/1396/en

In September we obtain the bark of an oak — preferably one grown within the farm precincts — and a skull, preferably from an animal kept on the farm (Illustration 29). With older oaks whose bark is deeply fissured, it is advisable to scrape away the outermost layer — often lightly mossed — with a draw iron, and to use only the younger bark layers beneath. The mass, which already crumbles somewhat during removal, is then chopped thoroughly into a friable, crumbling structure. After slaughtering, the brain is removed from the domestic animal skull through the occipital foramen, together with any remaining flesh and skin adhering to the exterior. One then uses the upper portion of the skull and fills the cranial cavity — through that same opening in the occipital bone through which the nerve cord of the spinal column passes into the cerebellum — with the bark mass. The opening is sealed with a splinter of skull bone and made airtight with clay.