Merchant marine house flags and stack insignia

This USN H.O. publication was part of every USN & CG Signal Bridge/Pilot House Library; to assist in early and correct identification of merchantmen. The markings upon the ships funnel(s), or (smoke)stack(s), the House Flags distinctive marks, emblems and colors depicted therein could be discerned from several miles, with good binoculars. The ship could be signalled visually, as necessary, using the International Code of Signals by flaghoist or flashing light (Morse). From H.O 102, INTERNATIONAL CODE OF SIGNALS: CODE U; You are running into danger**strong text** **strong text**