Statistics for occurrence #1 of “U. S. Gun” in chapter 13 of Admiral David D. Porter, The Naval History of the Civil War.:

... U. S. Gun
James B. Eads engaged to build gun-boats. depot established at Cairo. Navy yard at Mound City. Flag-officer Foote ...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
U. S. Gun 8 8 0 0 0 user votes
U. S. Gunboats 4 0 0 0 0 user votes

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