A. T. Mahan,
From Sail to Steam, Recollections of Naval Life
“ To such doubters, before the war, there was always ready the routine reply that a navy protected commerce; and American shipping, then the second in the world, literally whitened every sea with its snowy cotton sails, a distinctive mark at that time of American merchant shipping. In my first long voyage, in 1859, from Philadelphia to Brazil, it was no rare occurrence to be becalmed in the doldrums in company with two or three of these beautiful semi-clipper vessels, their low black hulls contrasting vividly with the tall pyramids of dazzling canvas which rose above them. ”
