Statistics for occurrence #1 of “Slack” in chapter 2, page 36 of Col. John M. Harrell, Confederate Military History, a library of Confederate States Military History: Volume 10.2, Arkansas:

...icers and men would quickly spring forward to obey it. One of his aides, Colonel Allen of Saline, was killed while receiving an order. Weightman and Cawthorn and his adjutant were mortally wounded; Slack was fearfully lacerated by a musket ball, and Clark
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
† Slack 107 20 39 4 0 user votes
William Y. Slack 59 0 7 0 0 user votes
W. Y. Slack 55 0 3 0 0 user votes
William Yonely Slack 26 0 2 0 0 user votes
Charles Slack 22 0 6 0 0 user votes
J. R. Slack 22 0 2 0 0 user votes
Charles W. Slack 16 0 0 0 0 user votes
James R. Slack 11 0 7 0 0 user votes
C. W. Slack 10 0 0 0 0 user votes
Charles B. Slack 8 0 0 0 0 user votes
John Slack 4 0 0 0 0 user votes
A. H. Slack 2 0 0 0 0 user votes
C. H. Slack 2 0 0 0 0 user votes
E. H. Slack 2 0 0 0 0 user votes
F. Slack 2 0 0 0 0 user votes
J. T. Slack 2 0 0 0 0 user votes
Thomas Slack 2 0 0 0 0 user votes
Wm Slack 2 0 0 0 0 user votes
Hedgman Slack 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.