Max Ringelmann

Maximilien Ringelmann (10 December 1861 to 2 May 1931), known as Max Ringelmann, was a French professor of agricultural engineering, born and died in Paris. He studied at the Institut National Agronomique, taught rural engineering from 1881, and from 1888 directed the Paris facility for testing agricultural machinery. In 1888 he proposed the grid of smoke density charts known as the Ringelmann scale, and he was elected to the Academie d'Agriculture in 1887. Between 1882 and 1887 at the agricultural school at Grand-Jouan he had students pull on a rope singly and in groups and noticed that the effort of a group was less than the sum of the individual efforts. Published in 1913, this Ringelmann effect, also called social loafing, is one of the earliest findings in the history of social psychology, and some describe him as a founder of the field.