What did Camillo Golgi discover and how does it deal with cell? When did he discover this?

Camillo Golgi contributed much to the study of the brain. 
Thanks to a method for staining nervous tissue he created (now known as Golgi's method),
the paths of nerve cells in the brain were viewable for the first time in history.  It
is because of this discovery that the theory stating the nervous system is made up of
individual cells was accepted (also known as the neuron
doctrine), and the anatomy of neurons became a viable
study.

Also the result of Golgi's research was the
discovery of the Gogli apparatus found in most eukaryotic cells
(cells contained within membranes).  This apparatus is fundamental for
the processing and packaging of proteins and lipids after synthesis for secretion.  With
relation to the brain, the Golgi apparatus is fundamental for the release of
neurotransmitters from neuron
cells.