Asked by pistol

this is one photographic process used in the mid-1800s
Answered by Writeacher
http://www.google.com/search?q=photographic+process+1800s&rlz=1C1GGGE_enUS379US379&oq=photographic+process+1800s&aqs=chrome.0.57j0l3j62l2.7217&sugexp=chrome,mod=1&sourceid=chrome&ie=UTF-8