Seven circular celluloid-covered steel buttons, coloured to imitate horn. Celluloid, like Parkesine, is based on cellulose nitrate but includes camphor as a plasticiser making moulding easier. It was patented in America in 1870. Early applications included billiard balls, knife handles and small decorative items, often succesfully imitating ivory or tortoiseshell. Once it was cast as film, celluloid made the development of cinema posible.
© Science Museum / Science & Society Picture Library