Except for the Monitor vs. Virginia ( Merrimack ), naval battles get short shrift in Civil War history. James M. McPherson fills that gap with War on the Waters, The Union and Confederate Navies, 1861-1865. Land battles were certainly decisive, but the Union might have lost the war without Gideon Welles and the Navy Department. McPherson even makes a strong argument that Rear Admiral David Glasgow Farragut deserves to be ranked with generals Grant and Sherman when giving credit for the Union victory. Inventions and innovations by both the Confederate States and the United States revolutionized naval warfare. Steam power, screw propellers, ironclads, submarines, weaponry, and naval tactics all advanced significantly during those four years. By Appomattox, the United States owned the largest navy in the world, and arguably the most technologically advanced. War on the Waters does an admirable job of describing blue-water and brown-water (river) battles and explaining the signi...