Statistics for occurrence #1 of “Johnson's Island” in chapter 1.24, section c.1.24.376, page 379 of Southern Historical Society Papers, Volume 17.:

...t until after Christmas. I am well acquainted with a Confederate captain now living in Richmond, a perfect Hercules in physique, who (if I remember rightly) weighed fifty pounds less upon leaving Johnson's Island than when he entered its prison walls.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
† Johnson's Island (Ohio, United States) 590 8 12 0 0 user votes
Johnson's Island (Illinois, United States) 2 0 0 0 0 user votes
Johnson's Island (Florida, United States) 0 0 0 0 0 user votes
Johnson's Island (Michigan, United States) 0 0 0 0 0 user votes
Johnson's Island (North Carolina, United States) 0 0 0 0 0 user votes
Johnson's Island (Tennessee, United States) 0 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.