In 1851 englishman Frederick Scott Archer invented the wet collodion process, which supplanted the daguerreotype and only lasted a little over 20 years.
In 1852 he also published the first manual on wet collodion called the Manual of the Collodion Photographic Process.
The discovery of the wet colloidal process is one of the most important milestones in the history of photography. But he had his shortcomings. Ambrotype differs from the original collodion process in that a positive image is obtained directly from a glass negative, which is viewed against a dark background. The image on the plate was not durable: people put black paper on it, getting a positive image, and then inserted it into a “frame”, and so the photo adorned the chest of drawers until time took its toll. Under the influence of oxygen, the silver oxidized and spoiled the plate.In 1854, James Anson Cutting patented a method for mounting wet collodion plates. He came up with the idea of covering the side with a layer of collodion with varnish, and then covering it with a second glass on top. Thus, the access of oxygen to the collodion layer was completely prevented, which contributed to longer storage.
James called this method "ambrotype" - which means "immortal".