I am no British military expert, so do not hold this against me.
If you google some Highlander images, all captains have the second pictured sword. Perhaps the other sword was used byNCO's or Junior officers, if the Military has them. My book about the revolutionary war (How dare I compae it, but Highlanders were in this war) All Field officers have them (Second picture) They are called claymores.
If you google some Highlander images, all captains have the second pictured sword. Perhaps the other sword was used by