[Je veux présenter mes excuses devant un capitaine de frégate française qui m'a attaqué hors du côte de Cuba.]

Une petite précision.

Dans l'armée Française l'utilisation du "mon" n'est usuel dans la marine. On le dit pour l'armée de terre (et peut-être pour celle de l'air). Dans la marine on ne dit que "bonjour capitaine". Ou mieux, si le capitaine a le commandement d'un bâtiment, on le nomme comandant. Donc "bonjour comandant".

Et là, tu es au top !

 

Dans la Marine il y a Mon Dieu et mon cul, pas mon capitaine!

[Question of the day - ship rig vs brig rig]

A passage from a book I found about the convertion to ship rig

[Question of the day - ship rig vs brig rig]

While not a direct answer to your question I have found an interesting article on wikipedia about the difference between a Snow (derived from Three masted ships) and a Brig.

 

https://en.wikipedia.org/wiki/Snow_%28ship%29#Difference_with_brig

Difference with brig

While in the 21st century, the snow and the brig look closely related, this is in fact not the case. The two rigs evolved from two opposite ends, with the brig evolving from the generally smaller brigantine and the much older snow evolving from the larger three masted ship.^[6]

The most visible difference between the brig and the snow is in the snow-mast stepped directly behind the main mast.^[7] On a snow, in contrast to the brig where the gaff and boom are attached directly to the main mast, the gaff and, in later times, the boom were attached to the snow-mast. The use of this characteristic snow mast offered several advantages over attaching the gaff directly to the main mast.^[8]

The yoke (or jaw) of the gaff and the lacing of the gaff sail on a snow could move freely on the snow mast, not hindered by the iron bands that held together the (main) mast, nor limited by the main yard. As a result of the latter, the gaff could be raised higher than the main yard and independently of it. The resulting freedom allowed a snow, in contrast to the brigs, to fly a main course without complications, as they typically did.^[9]

However, in the late 18th century, brigs started to set main courses as well, which gave rise to the term snow-brig. The difference was lessened even further when the snow-mast was replaced by a steel cable, at which point the term snow-brig gradually became interchangeable with the term brig and the term snow fell in disuse.