Welcome, Angelique's portrait again. Are we hearing brand new classic DS music here? Have Barn and Carolyn forgotten they're desperate to get Julia's journal? I've always thought that at this point, they were just pushing past the bits of the pre-1795 storyline whether it made sense or not, but now I think it all may make sense that B&C have disengaged from battling Julia.
Julia has temporarily made herself valuable at Collinwood, as a doctor for Vicki, at least for now, as opposed to just being an historian/freeloader on her way out of town. Barnabas could still kill her, but it would create unpredictable ripples in things.... more suspicion, just when ECS accused B of knowing what's going on with Vicki for one thing.
If he's not killing her, he needs her cooperation re Vicki for info and access. Once he decides this, he starts allowing himself to notice that Julia never gave him away through all the threats and throttlings.... and relaxes about the damn notebook. I don't know if this makes her safe at all in the longer run, but for now it might.
Barnabas doesn't care who hears him, as he burns the portrait, and bellows his head off. Nice sense of hightened reality in this stretch of 1968. It all seems to promise great things ahead.