Unlike the motion studies of Muybridge, who depicted movement as a series of discrete moments on separate, sequential negatives, Marey's analyses of motion are characterized by multiple exposures on a single photographic plate. In this photograph, Charles Fremont, a civil engineer who assisted Marey in his laboratory, used Marey's method to study blacksmiths at the anvil. Fremont's photographic investigations into the conservation and expenditure of energy during human labor established principles that laid the foundation for modern industrial production. ?tienne-Jules Marey (March 5, 1830 - May 21, 1904) was a French scientist, physiologist and chronophotographer. In 1882 he made his chronophotographic gun. This instrument was capable of taking 12 consecutive frames a second, and the most interesting fact is that all the frames were recorded on the same picture. His research on how to capture and display moving images helped the emerging field of cinematography. He died at the age of 74.