Statistics for occurrence #1 of “Washington” in chapter 1.1, page 15 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 7: Prisons and Hospitals.:

... Washington
...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Washington (United States) 21,192 174 3,586 2 0 user votes
Washington (Washington, United States) 232 0 0 0 0 user votes
Washington (Virginia, United States) 224 0 4 0 0 user votes
Washington (Alabama, United States) 88 0 0 0 0 user votes
Washington (West Virginia, United States) 14 0 2 0 0 user votes
Washington (Georgia, United States) 6 0 6 0 0 user votes
Washington (Idaho, United States) 4 0 4 0 0 user votes
Washington (California, United States) 2 0 0 0 0 user votes
Washington (Missouri, United States) 2 0 2 0 0 user votes
Washington (Louisiana, United States) 1 0 1 0 0 user votes
Washington (Arkansas, United States) 0 0 0 0 0 user votes
Washington (Kansas, United States) 0 0 0 0 0 user votes
Washington (Maine, United States) 0 0 0 0 0 user votes
Washington (Michigan, United States) 0 0 0 0 0 user votes
Washington (Minnesota, United States) 0 0 0 0 0 user votes
Washington (Mississippi, United States) 0 0 0 0 0 user votes
Washington (Missouri, United States) 0 0 0 0 0 user votes
Washington (Nebraska, United States) 0 0 0 0 0 user votes
Washington (Nevada, United States) 0 0 0 0 0 user votes
Washington (New Jersey, United States) 0 0 0 0 0 user votes
Washington (New Mexico, United States) 0 0 0 0 0 user votes
Washington (New Mexico, United States) 0 0 0 0 0 user votes
Washington (Ohio, United States) 0 0 0 0 0 user votes
Washington (Ohio, United States) 0 0 0 0 0 user votes
Washington (Ohio, United States) 0 0 0 0 0 user votes
Washington (Oklahoma, United States) 0 0 0 0 0 user votes
Washington (Texas, United States) 0 0 0 0 0 user votes
Washington (United Kingdom) 0 0 0 0 0 user votes
Washington (Utah, United States) 0 0 0 0 0 user votes
Washington (Vermont, United States) 0 0 0 0 0 user votes

† This entity has been selected by the automated classifier as the most likely match in this context. It may or may not be the correct match.