Eastman roll film holder. An early attempt to reduce the weight of the number of glass negatives when working away from the studio. Forerunner of the cut-film. The holder was loaded with a length of film without paper backing and was returned for processing to Eastman. The later development was the paper safety backing which became the standard way for the smaller sizes that became popular. Some workers evolved personal methods of processing the films in their own darkrooms. Not very successful because of the difficulty in keeping the film level in the focal plan of large cameras.