Quarantine "yellow jack" but this was also a name for yellow fever, which probably derives its common name from the flag, not the color of the victims (cholera ships also used a yellow flag). The plain yellow flag ("Quebec" or Q in international maritime signal flags) probably derives its letter symbol for its initial use in "quarantine", but this flag in modern times indicates the opposite—a ship that declares itself free of quarantinable disease, and requests boarding and routine port inspection. Australia has perhaps the world's strictest quarantine standards. Quarantine in northern Australia is important because of its proximity to South-east
Flag of Natal Flag of Natal The flag of Natal was the official flag of the South African colony of Natal from 1870 to 1910. It formed part of a system of colonial flags that were used throughout the British Empire. In a series of decisions made in 1864, 1865, and 1869, the British government decided that every colony should have a distinctive badge, to be displayed on flags at sea. The governor was to display the badge in the centre of the Union Jack when travelling by sea; vessels owned by the colony's government were to display it in the fly of