Flavia nods, trying to recall the medicinal properties of aconite--as much for the mental exercise as to discern whether Mr. Lupin indeed fit any of the potential diagnoses. He didn't look in need of anesthetic; not wheezing enough for asthma; possibly quinsy, if only she could remember what, precisely, quinsy was.

"That's the interesting thing about poisons, isn't it?" she muses. "Too much, and one's dead as a doornail, but just enough and you're right as rain."