Statistics for occurrence #1 of “Commander J. D. Johnston” in page 567 of Admiral David D. Porter, The Naval History of the Civil War.:

..., speed 7 1/2 knots; battery, four 10-inch columbiads of 16,000 lbs. and two 7 1/2-inch Brooke rifles of 19,000 lbs. The Tennessee was the flag-ship of Admiral Franklin Buchanan, and was commanded by Commander J. D. Johnston . The following gun-boats also belonged
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