Purely from a Latin standpoint, here... since I've forgotten where this chapter is in conjunction with the rest of the story:
means 'narrow' or 'confined'.
is actually a pretty broad word, usually meaning 'affair' or 'thing', and it's meaning really depends on context -- it can mean a lot of different things depending on how and where it's used. In this case there isn't much context, so I can't say for sure exactly how it's used. Put them together as you will.
: Right, so apparently this means something a little different. My trusty Cassell's dictionary mentions that Cicero used the same phrase (well, the plural version), and he took it to mean 'uncertain circumstances'. Which pretty much goes to show the broad scope of the word res
more than anything, and that context = everything.