how do the captain and black dog react to one another? how does this make Jim feel?

When Bill finally appears, he looks like he has seen a ghost when he sees the stranger, whom he identifies as Black Dog, one of his shipmates. After telling the boy to leave, the two talk together in low voices. The only thing that the boy overhears is the captain speaking about all "swinging," (meaning hanging), before there is a loud commotion. After the outcry, Black Dog, with a cut on his shoulder flees, the captain pursues him, both with drawn cutlasses. The captain aims at Black Dog but misses and hits the inn's signboard instead, leaving Black Dog to escape.

Afterwards, the captain orders rum but before Jim can deliver it to the captain, he hears a loud fall and finds the captain unconscious on the floor.

Oh, I think this makes Jim feel rather scared and confused. He has two notorious pirates duking it out in his establishment. Dr. Livesy shows up to check on Jim's father which is a relief for Jim to have an adult male he can trust on the premises.