Olfactory bulb image by Camillo Golgi, 1875
In 1875 the physician Camillo Golgi invented the reazione nera (black reaction) cell-staining technique, which allowed anatomists to view individual neurons in their entirety for the first time. Potassium dichromate and silver nitrate are added to preserved nervous tissue, and the neurons become visible as tiny silver chromate crystals form inside the cells.
Golgi used the technique to make detailed neuronal maps, such as this drawing of a dog’s olfactory bulb, made in the year he discovered the reaction. The technique became widely known as “Golgi’s method” and marks the beginning of modern neuroscience.
Click here to see other images from the book Portraits of the Mind by Carl Schoonover