The brain under the knife: serial sectioning and the development of late nineteenth-century neuroanatomy.

Major changes took place during the last quarter of the nineteenth century in the ways that the brain tissue was maintained, manipulated and studied, and, consequently, in the ways that its structure, functions and pathologies were seen and represented in neurological literature. The paper exemplifies these changes by comparing German neuroanatomy in the 1860s and early 1870s (represented above all by Theodor Meynert) with the turn-of-the-century view of the brain (represented by Constantin von Monakow and others). It argues for the crucial importance of a method--serial sectioning--to the emergence of the new view of the brain. Serial sectioning in turn owes its existence to the new techniques in staining and sectioning that were introduced in the 1870s and 1880s. In particular, the paper highlights the role of a cutting device, the microtome, in enabling serial sectioning and in thereby contributing to the emergence of a new view of the brain.