Note 193 — Chapter IX
Reading edition
Until after the middle of this century there were in the British navy three flags of the same general design, but with red, white, and blue grounds. Admirals were divided into three classes, of the Red, the White, and the Blue; and, according to their classification, ships under their immediate command showed the corresponding ensign. Nelson being at this time a rear-admiral of the Blue, his ships would usually carry the blue flag, almost invisible at night.
At the present day all British naval vessels wear the white flag, and merchant ships the red.