(1) (1821) German physician and physicist Hermann von Helmholtz is born. He measured the speed at which a message is carried along a nerve fiber and also focused his research on the mathematics of the eye.
(2) (1870) Italian physician and educator Maria Montessori is born. She developed the Montessori educational approach for learning, which she developed when working with special needs children.
(3) (1925) Canadian physician and academic Moran Campbell is born. He was the founding chair of McMaster University’s Faculty of Health Sciences and also invented the Venturi mask, which delivers oxygen to patients on controlled oxygen therapy.