Quarantine Edinburgh and Leith, grain was from that date declared to be a non-susceptible article. About 1788 an order of the council required every ship liable to quarantine, in case of meeting any vessel at sea, or within four leagues of the coast of Great Britain or Ireland, to hoist a yellow flag in the daytime and show a light at the main topmast head at night, under a penalty of After 1800, ships from plague-countries (or with foul bills) were enabled to perform their quarantine on arrival in the Medway instead of taking a Mediterranean port on the way for
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,