We see it everyday: the street signs on the way to work, the menu at lunch, the countless websites visited over the course of the day, maps, charts and graphs, all use color to communicate their meanings. And this has been going on for who knows how long. Now I’m wondering what the first known example of such a use of color really is. My guess is that it probably dates back much farther than we would think.
One example of using color to communicate that started back in 1857 are the international maritime signal flags. While only using red, yellow, blue, white and black, these flags communicate special messages and have the capability to be used as individual letters to spell out any necessary messages from ship to ship while out at sea.
If you’re up for it, after studying up with this post jump over to the flag test to see if you’re ready for the open seas.
The Main Alphabet
C
Affirmative. With three numerals, course in degrees magnetic. |
D
Keep clear of me; I am maneuvering with difficulty. With two, four, or six numerals, date. |
E
I am altering my course to starboard. |
F
I am disabled; communicate with me. |
I
I am altering my course to port. |
J
I am on fire and have dangerous cargo on board: keep well clear of me, or I am leaking dangerous cargo. |
M
My vessel is stopped and making no way through the water. |
N
Negative.I am dragging my anchor. |
Q
My vessel is “healthy” and I request free pratique. |
R
The way is off my ship. With one or more numerals, distance in nautical miles. |
U
You are running into danger. |
V
I require assistance. With one or more numerals, speed in kilometres per hour. |
W
I require medical assistance. |
X
Stop carrying out your intentions and watch for my signals. |
The History of Signal Flags
The International Code of Signals has been in continuous use since 1857, when it was published by the British Board of Trade as a means of maritime communications. The original Code contained 17,000 signals using 18 signal flags, some of which were specific to the United Kingdom. The Code was revised in 1932 to include seven languages: English, French German, Italian, Japanese, Spanish and Norweigan. When the code was revised again in 1969, the revision included Russian and Greek, plus giving a complete meaning to each of the alpha-numeric nautical signal flags.
– Reed’s Nautical Almanac
Check out the numeric and secondary signal flags at wikipedia.