My intent is not to be argumentative, but I have found a reference which
better describes the "first blood" duel. The work is "Duell-Codex" by
Gustav Hergsell, page 74:

"If the motives for the duel are of a less serious nature, or both opponents
only took refuge in arms due to a wrong interpretation of the points of
honor, the seconds have to agree that the fight will be continued no further
after the first injury, even if it is light. This condition will have to be
communicated to the duellists just before the fight."

Hergsell is taking the Central-European position that tried to discourage
"first blood" duels preferring instead that the principles duelled until one
party was incapacitated. The French, according to the accounts I have read,
were much more disposed to "first blood" duels.

Respectfully,
Brian House
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