Visual Pathways c . 1901 (Spain) 1 sheet, drawing with India ink on paper; 21,8 × 31,2 cm Cajal Legacy Cajal Institute (Spanish Main Research Council). Madrid. Cajal Legacy-26115 Our understanding of the human central nervous system took a major step forward at the beginning of the 20th century, with the work of the Spanish physiologist Santiago Ramón y Cajal (1852-1934). Ramón y Cajal contributions to neuroanatomy are manifold but his most important was without doubt the clarification of the nature of nerve cells, showing the individual character of neurons, and the highly interconnected networks formed by these cells. His careful and striking drawings are superb examples of scientific diagrams and of illustrations carefully conceived to explain complex anatomical and physiological structures. The document presented here is a drawing made by Ramon y Cajal around 1901, showing an outline of the optical pathways. The document is a general scheme of the nerve cells from t...