Statistics for occurrence #1 of “McClurg” in chapter 5, page 65 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 5: Forts and Artillery.:

...appointed first-lieutenant and assigned to duty in the ordnance department. Hence, and because of heavy losses, the battery was merged, at the expiration of the year for which it had enlisted, with McClurg 's Battery, and its history after that time is the history of that battery.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
McClurg 13 2 3 0 0 user votes
A. C. McCLURG 24 0 14 0 0 user votes
Alexander C. McClurg 8 0 0 0 0 user votes
James McClurg 5 0 1 0 0 user votes
Joseph W. McClurg 4 0 0 0 0 user votes
J. W. McClurg 2 0 0 0 0 user votes
W. McClurg 2 0 0 0 0 user votes
D. C. Mcclurg 1 0 1 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.