The document was printed during or soon after the American Civil War and we know this because of the background of the "Army of the Potomac" and this was a time of transition in photographic processes. Daguerreotypes, Ambrotypes and Tintypes were single positives that were purchased as soon as they were made. With the negative processes the person had to return to the studio to obtain the final print or have it sent on. This added a level of uncertainty to the photographer unless he received payment in advance and one of the paragraphs explains this to the public.
