Albrecht von Haller, a Swiss physician and physiologist, made note in his 1747 book on physiology that the "water" in the brain was secreted into the ventricles and absorbed in the veins, and when secreted in excess, could lead to hydrocephalus.
Nahaja se v subarahnoidalnem prostoru (med arachnoideo mater in pio mater), v možganskih ventriklih in centralnem kanalu hrbtenjače.