Such was the case with Horatio Nelson. He had always been a brilliant strategist, but wasn't elevated to hero's status till after Battle of Trafalgar, he was victorious, but for that he also gave his life (out of all things, to a musket ball from a sniper sitting atop the mizzentop of the French ship of the line Redoutable).
Brits won because pretty much everything went as Nelson had planned. Unable to direct much of the action that day, being mortally wounded. The exact count of orders Nelson issued during Battle of Trafalgar was...2.
These messages were broadcasted to the fleet via signal flags hoisted up the mizzenmast (the mast immediately after the main mast) on Nelson's flag ship Victory. They were displayed word by word, each word represented by a 3 flags arranged according to the 1803 Popham's code book. Illustrated below.
The last 4 letters D-U-T-Y were each signaled by 2 digits. Interestingly, this system omitted the letter "J" due to sailor superstition. More interestingly, such tradition is still in place today.
Nelson's last order was illustrated with 2 flags, for the letter O. Or in other words, a code within a code. The letter "O", when displayed alone, meant " Engage the enemy more closely".
In the above example, we also saw use of the first substitute flag.
A substitute flag is used to represent another flag that's currently being used.
A substitute flag is used to represent another flag that's currently being used.
In the common 4 letter system, there are 3 substitute flags, for repeating first, second and third letter in the message respectively without requiring the same flag at 2 positions simultaneously. (Or a second set of flags would be required). There are also systems that use 5 flags, with a 4th substitute flag.
F-O-O-D = F-O-2sub-D
T-R-E-E = T-R-E-3sub
A-A-R-O-N = A-1sub-R-O-N
F-O-O-D = F-O-2sub-D
T-R-E-E = T-R-E-3sub
A-A-R-O-N = A-1sub-R-O-N
More on codes
The systems used by militaries today are derivatives of the international signal system installed in the 1850s, but differ from country to country.
Here are our upcoming 1:350 signal flag sets. One for U.S. Navy, and the other for Imperial Japanese Navy.
The U.S. Navy decal includes 2 size 10 sets and 2 size 3 sets of flags, also all the special flags, pennants and rank displays. The size 3 set, is mathematically equivalent to size 10 in 1:700, so this product actually suits both scales.
The Japanese decal includes 2 types of flags. One set according to WWII Japanese Navy regulation, and the other based on measurements from the impressive flag collection of the Mikasa Museum.
Design of hoists are different on the 2 sets, the 2 navies had different ways of hanging their flags. The decals come with detailed instructions.
Another use of signal flags is to display ship's ID. Each ship has a 4 letter ID, also known as radio call sign.
More on ship ID
USN
IJN
Some examples of ship ID and messages.
A century after Nelson's death, Japanese Admiral Tōgō Heihachirō displayed a similar message to encourage his men during Battle of Tsushima (Russo-Japanese War). This time, the long message was pre-assigned to one specific flag (Z) and hoisted up on Mikasa. Hanging of Z-flag became a Japanese military tradition. One example being the carrier Akagi displaying the Z-flag before the attack on Pearl Harbor.
NW35041 1:350 USN Flag decal set
NW35042 1:350 IJN Flag decal set
NW35042 1:350 IJN Flag decal set
Nice post, thanks for writing it. I've been looking for a clear illustration of the Popham's code all morning.
ReplyDeleteI think the number 16 (flags 1 & 6) was the reference for "Engage the enemy more closely" ("O" was just the letter this translates to when spelling something out). The same way the number 253 (flags 2, 5 & 3) was the code for "England" etc. Same thing really but keeps the consistency with the other sets of flags shown.
It's always interested me how they knew when flags meant a letter or a phrase. In the example above, 16 meant both "O" or "Engage the enemy more closely".
Would also love to see a list of the pre-determined phrases too, perhaps I'll try and find a copy of the book.
Thanks again, Ben.
Thanks for your interests, although, the write-up was to illustrate the signal flags, not the code system :)
ReplyDeleteThere were hundreds of entries in the code book, and a number representing each entry. Some numbers, especially the single digits, each represent more than a single meaning. The number 14, represents both the capital letter "O" and the order "engage enemy more closely".
What I didn't mention though, was that the flags were not assigned during battle of Trafalgar according to the 1803 Popham's book. Still the 10 flags, but they were shuffled and only the flag officer knew which flag meant which number. This was because the 1803 Popham's code was already compromised at the time, and the 1805 code book had not been distributed.
The first message was however, flown according to the original flag assignments because it was for all sailors to observe. The "engage enemy more closely" order, was flown with the cyphering of new flag assignments, where the one flag was unchanged, but the six flag was reassigned to the numerical value 4.
Here's link to the ebook
http://books.google.com/books?id=qxZEAAAAYAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false