Liberty Loan Parade at Philadelphia, Pennsylvania, 28 September 1918
Naval Aircraft Factory float, featuring the hull of a F5L patrol seaplane, going south on Broad Street, escorted by Sailors with rifles. Note the crowd of onlookers. This parade, with its associated dense gatherings of people, contributed significantly to the massive outbreak of influenza which struck Philadelphia a few days later. U.S. Naval History and Heritage Command Photograph.