Before I make any comments ...
Click
HERE to see an "animated" version of the "Battle of Trafalgar."
(You can also "fight" the Battle of Waterloo!)
Ok ...
We have said that we will deal harshly with "nitpickers" here at GW-PC !!!
But, when everyone is correct (and in agreement) ... It's ok ...
Rocroi said that a "Royal Navy" officer had a "blue" uniform jacket. That is correct!
However,
Stéphane already knew that!
But, let's not forget that in 1805 the "Royal Marine" officer wore a "red" jacket! ...

(It appears that we may only have a French-English translation problem. In English the word "Marine" refers to the "soldiers" of the Navy. And, "Navy" refers to the "sailors" of the Navy.)
A Royal Marine officer c.1805