Confession: This snippet starts by saying the distraction we’ve been talking about all this time (the sounds of the night) isn’t the real reason why the narrator is avoiding their obligations (to study Burke and Wills).
Status of the victim: The narrator updates us about the victim, but in an emotionally neutral way.
Downplaying concern: Then they deny they’re concerned.
Of course, because of all the resonant details to this point, we know the narrator is not telling the truth, because we have been coaxed into feeling worried ourselves.