Quarantine with a disinfecting stove, have a right to navigate the Canal, in quarantine, subject only to the landing of those who were suffering from plague. Plain yellow, green, and even black flags have been used to symbolize disease in both ships and ports, with the color yellow having a longer historical precedent, as a color of marking for houses of infection, previous to its use as a maritime marking color for disease. The present flag used for the purpose is the "Lima" (L) flag, which is a mixture of yellow and black flags previously used. It is sometimes called the
Flag of Australia Union Flag in the UK, when the House of Representatives proclaimed that the Blue Ensign "should be flown upon all forts, vessels, saluting places and public buildings of the Commonwealth upon all occasions when flags are used". The government agreed to fly the Blue Ensign on special flag days, but not if it meant additional expense, which undermined the motion. The Blue Ensign could only be flown on a state government building if a state flag was not available. On 2 June 1904 a resolution was passed by parliament to replace the Union Jack with the "Australian Flag" on forts.