SHEILA TERRY / SCIENCE PHOTO LIBRARY SHEILA TERRY / SCIENCE PHOTO LIBRARY
Manufacture of guncotton in 19th century France. Cotton is immersed in a solution of nitric and sulphuric acid to convert the cellulose in the cotton to nitrocellulose (cellulose nitrate), a highly inflammable compound. This eventually became the main ingredient in modern gunpowder, replacing the saltpetre, and was an essential component of the earliest man-made fibres and plastics. After immersion the acids are recovered using a press. The nitrocellulose is then thoroughly washed before drying otherwise it would be dangerously unstable.
Model release not required. Property release not required.