Statistics for occurrence #1 of “Zzz” in chapter 50 of The Atlanta (Georgia) Campaign: May 1 - September 8, 1864., Part I: General Report.:

...he campaign. Very respectfully, your obedient servant, L. P. Bradley, Brigadier-General, Commanding. Capt. George Lee, Asst. Adjt. Gen., Second Div., Fourth Army Corps. Zzz Hdqrs. Third Brig., Second Div., 4TH Army Corps, Near Atlanta, Ga., September 13, 1864.
...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
† ZZZ 3,532 210 0 0 0 user votes
Interrogavi Terramn Zzz 4 0 0 0 0 user votes
March Zzz 2 0 0 0 0 user votes
S. ZZZ 2 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.