Statistics for occurrence #1 of “U. S. Mortar” in chapter 18 of Admiral David D. Porter, The Naval History of the Civil War.:
...ccomplished. To yourself and the officers and seamen of the mortar flotilla the Department extends its congratulations. I am, respectfully, Gideon Welles. Commander David D. Porter, Commanding U. S. Mortar Flotilla, etc., etc....
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|†||U. S. Mortar||6||4||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.