Meanwhile, in Colby's "diary" (actually, Walt Whitman's written account, drawn through Colby's eyes):
Following the big parade for the 4th of July 1863, news arrives of a hard-won Union victory at Gettysburg!
SOURCE TEXT = Walt Whitman: Memoranda During the War (1875-76)
Yep, you recognized him! That "older fellow" is indeed Walt Whitman, who originally recorded this moment (which I have drawn through Colby's eyes). Here's the source, so you can see how I've selected & arranged Whitman's original text:
As I went down the Avenue, saw a big flaring placard on the bulletin board of a newspaper office, announcing "Glorious Victory for the Union Army!" Meade had fought Lee at Gettysburgh, Pennsylvania, yesterday and day before, repuls'd him most signally, taken 3,000 prisoners &c. (I afterwards saw Meade's despatch, very modest, and a sort of order of the day from the President himself, quite religious, giving thanks to the Supreme, and calling on people do same, &c.)
I walk'd on to Armory Hospital—took along with me several bottles of blackberry and cherry syrup, good and strong, but innocent. Went through several of the Wards, announc'd to the soldiers the news from Meade, and gave them all a good drink of the syrups with ice water, quite refreshing.........Meanwhile the Washington bells are ringing their sundown peals for Fourth of July, and the usual fusillades of boys' pistols, crackers, and guns. (p.19-20)
Here, then, is a useful alignment of our sources. Walt Whitman visits Armory Hospital, where Sarah Low is currently working as a nurse. Colby & co. are helping to carry wounded to hospitals (although probably NOT to Armory, as Colby describes a 2+ mile transit by stretcher & Armory is next to a boat landing where wounded could arrive by boat; but still...). This is the kind of topical convergence that helps me flesh out the details of one source's story with the details of another. If I allow my Colby (character) to cross paths with my Whitman & Low (characters), their composite experience will help us understand their time.
I have no historical PROOF that they crossed paths -- that's MY fictional conceit in the interpretive process of drawing this narrative.
The sundown DC skyline is taken from this "Early photographic view of Washington, D.C. from the Capitol, looking southeast":
Whitman's text provides a poppin' soundtrack to the dimming scenery... Just imagine the relief of the capital city, which has for days has awaited word of whether the union "can long endure"...!