The ambrotype process (from Greek ambrotos, "immortal") or amphitype is a photographic process that creates a positive photographic image on a sheet of glass using the wet plate colloion process. It was patented in 1854 by James Ambrose Cutting of Boston, in the United States. The wet plate collodion process was invented just a few years before that by Frederick Scott Archer, but Cutting used it as a positive, instead of a negative.