ABSTRACT
The introduction of the microscope into the study of histology has been in nineteenth century for the world of the infinitely little, what at another period of human development the intervention of the telescope was for the exploration of the sidereal world. It has rendered distinctly visible all those myriads of elements which, from the extreme smallness, were concealed from the eyes of our predecessors. The general view of cerebral topography having thus been fixed by the processes, the regions of more delicate texture, the special points which it was necessary to study in the minute elements, were further sufficiently magnified and reproduced, with successively increasing powers. The cerebrospinal system in man and the vertebrates consists of three departments, independent one of another, and yet very intimately connected. These are: the cerebrum proper, the cerebellum and the apparatuses of cerebellar innervation annexed thereto, and the medulla spinalis and its encephalic expansions.
