Statistics for occurrence #1 of “Dec” in chapter 17, page 335 of Emilio, Luis F., History of the Fifty-Fourth Regiment of Massachusetts Volunteer Infantry , 1863-1865:

...an 80 Independence, Ia. Knowles, Alfred H.; 1st Lieut. 28 Jan 42 Orleans; single; plumber; Orleans. 2d Lt 7 Oct 63, must. 7 Dec; 1st Lt 4 Feb 64, must. 30 Mch. Resigned 21 Feb 65. Wounded 9 Dec 64 Deveaux Neck, S. C. Other service:—Co. F 24th Mass. 7 Oct 61, Sergt. Arlington, Mass.
...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Nov Dec 390 390 0 0 0 user votes
Dec 638 0 6 0 0 user votes
M. O. Dec 26 0 0 0 0 user votes
John O. Dec 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.