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
Götheborg (ship) ordinary, rectangular flag. Swedish warships, or ships carrying a military commander, fly the Swedish ensign a triple-tailed or swallowtail and tongue version of the rectangular flag. The Swedish East India Company displayed a fork-tailed or swallow-tailed flag on their ships. The intention was that the ship should resemble a warship and thereby not attract pirates. This was against the rules and regulations for flags at that time. The use of the swallowtail was prohibited in a royal decree in 1751, but the SOIC ignored this and ordered their flags in Canton instead. In a memorandum to the Riksdag in 2012,