Like his cousin, Charles Darwin, Francis Galton (1822 - 1911), worked on the study of heredity. He
founded the science of eugenics (the study of improving human races), and in 1865 documented his findings in his best-known work "Hereditary Genius, its Laws and Consequences". In the history of photograph
y, one attributes to Galton the development of composite photography
- a multiple exposure process in which he generated typological portraits.
As an anthropologist and statistician, Francis Galton embarked on a photographic mission in the late 1870s to produce “portraiture of the invisible.” Instead of making photographs of individual objects or things observable to the eye, Galton aimed to create photographs of ideas and concepts that encompassed all individuals within that class.
If you are a follower of his work, then there is a lecture on Galton's photographic work entitled "The Monstrous, the Meaningless, and Margins of Error", details of which can be found here