Barnabas' vampire abilities have me quite puzzled. The various things he did to frighten Trask - the voice, making the candles go out, the vision of the hand, dreams, etc. all seem to be things that Angelique as a witch would have done. I've certainly never heard of vampire having those sorts of powers. Back in the present, when he wanted to frighten Julia, he did something similar. He told Carolyn a story about where he learned to do this (I forget just who the person was who had taught him). I suppose this could have been the same thing, but it does seem rather strange.
Meanwhile, his "real" vampire abilities are quite suspect! He does manage to turn into a bat and dematerialize at times. He does manage to bite some people. Given that he's surviving, he must be getting blood somewhere (we saw graphic evidence of that in the beginning).
However, most times when he goes to bite someone, he bares his fangs, they see it and scream (I always thought that a vampire had some sort of hypnotic power that prevented them from screaming or resisting). So, he ends up trying to strangle them, and in most instances someone hears the screams and comes on the scene, forcing him to leave with the job undone! He seems extremely inept!!
