<Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2008) (Learn how and when to remove this template message) </Td> </Tr> <P> The gelatin silver process is the photographic process used with currently available black - and - white films and printing papers . A suspension of silver salts in gelatin is coated onto a support such as glass, flexible plastic or film, baryta paper, or resin - coated paper . These light - sensitive materials are stable under normal keeping conditions and are able to be exposed and processed even many years after their manufacture . This is in contrast to the collodion wet - plate process dominant from the 1850s--1880s, which had to be exposed and developed immediately after coating . </P> <P> The gelatin silver process was introduced by Richard Leach Maddox in 1871 with subsequent considerable improvements in sensitivity obtained by Charles Harper Bennett in 1878 . </P> <P> Gelatin silver print paper was made as early as 1874 on a commercial basis, but it was poor quality because the dry - plate emulsion was coated onto the paper only as an afterthought . Coating machines for the production of continuous rolls of sensitized paper were in use by the mid-1880s, though widespread adoption of gelatin silver print materials did not occur until the 1890s . The earliest papers had no baryta layer, and it was not until the 1890s that baryta coating became a commercial operation, first in Germany, in 1894, and then taken up by Kodak by 1900 . </P>

Where did the dry plate (gelatin-silver) system originate