Statistics for occurrence #1 of “S. M. E. Clark” in chapter 1.5, page 125 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 7: Prisons and Hospitals.:
...enth Louisiana; W. D. DuBarry, Twenty-seventh South Carolina; H. L. Allan, First W. Artillery; G. R. Cooke, First Maryland Cavalry; J. Bozant, First W. Artillery; C. Rossiter, First W. Artillery, and S. M. E. Clark , First W. Artillery (abbreviation for Washington Artillery).
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