Characters: Thirty brief sketches of human weaknesses and faulty behavior as manifested in everyday life or in peculiar circumstances. Examples include: the flatterer, the talkative person, the braggart, the miser, the gossip, the rustic, etc.
On piety: Moral discourse in fragmentary form. Examples.
On stones: A physiognomic work on those who study environmental issues. Varieties, types, and characteristics of minerals.
On fire: The study of fire, its nature in itself and in relation to other simple elements. Aristotelian influences.