[Harry said] "You're a lot braver now that you're back on the ground
and you've got your little friends with you," said Harry coolly. There
was of course nothing at all little about Crabbe and Goyle, but as the
High Table was full of teachers, neither of them could do more than
crack their knuckles and scowl. "I'd take you on anytime on my
own," said Malfoy. "Tonight, if you want. Wizard's duel. Wands only -
no contact. What's the matter? Never heard of a wizard's duel before,
I suppose?" "Of course he has," said Ron, wheeling around.
"I'm his second, who's yours?" Malfoy looked at Crabbe and
Goyle, sizing them up. "Crabbe," he said. "Midnight all right?
We'll meet you in the trophy room; that's always unlocked." When
Malfoy had gone, Ron and Harry looked at each other. "What is a
wizard's duel?" said Harry. "And what do you mean, you're my second?"
"Well, a second's there to take over if you die," said Ron
casually, getting started at last on his cold pie. (Harry Potter and
the Sorcerer's Stone)
By about 1770 however, the duel had undergone a number of important
changes. Firstly, unlike their counterparts in many continental
nations, English duellists had enthusiastically adopted the pistol and
few duels were now being fought with the sword. Secondly, the office
of 'second' had developed into 'seconds' or 'friends' being chosen by
the aggrieved parties to conduct their honour dispute. These friends
would attempt to resolve a dispute upon terms acceptable to both
parties and, should this fail, they would arrange and oversee the
mechanics of the encounter. By this time the values of the duel had
spread into the broader and emerging society of gentlemen.
So a combat between two gentlemen could continue until round two, so to speak.