The Dexter Blue Tide Flag - Maritime Code for Lamba

The International Maritime Flag for Lambda had many incarnations.  No doubt ,this signal flag was used by several navies, nations, and communities across time.  But its modern historical fame would begin as a pattern within the Royal Navy of the United Kingdom.  Lord Howe, Admiral of the Royal Fleet, put this pattern on the historical map in 1790 to indicate the numerical value of 'zero.'  By the battle of Trafalgar in 1803 this pattern was coded to 'six,' since a copy of the code book was lost to potential enemies.

Then sometime in the middle of the 1800s this flag became associated with the letter 'S.'  However with the USA it was associated with the letter 'J' and then with the number six.  By WWII, the UK was code this pattern the number 7.   Upon the dawn of the Space Age, all the major navies of the world would abandon this earliest of signal flags from the Enlightenment Era.

Today this flag well known to many of Generation X and below as the middle signal flag on a fictional restaurant at Bikini Bottom, The Krusty Krab.  However, it has a Sinister Blue Tide—meaning that the hoist is blue with a blue bottom and the fly is white.

Since 2020 this flag has been rechristened as the Greek Letter Lambda.  This new association gives the ancient pattern a new life.  Since zero, six, seven, and the other letters already have established patterns, it makes sense to adopt this flag a new symbol.