The American realist painter and photographer Thomas Eakins was one of the people who convinced Provost Pepper to sponsor Muybridge’s project. Eakins was interested in what physiology could tell the artist about the body in motion. In 1884, he constructed a shed near Muybridge’s outdoor studio at the University of Pennsylvania, and modified a Marey-wheel camera to make chronophotographs of men running and jumping. By 1885, as Muybridge perfected his multicamera system and abandoned his own experiments with a Marey-wheel camera, Eakins dissociated himself from the Muybridge project and left the university grounds to work on his own.
By June 1885, Muybridge was making up to 36 images at a time to document movement from three different angles. With assistants hired by the university, Muybridge worked right through until the fall. By October 1885, he had made close to 20,000 photographs.
During the winter of 1885, Muybridge organized and assembled the camera negatives, and printed them as cyanotypes (his working proofs). He then went back to his original negatives, enlarged them, and assembled them in composite glass plates. The 781 plates were printed as collotypes, put into portfolios, and sold by subscription in the fall of 1887.