In a mixture of reinterpretation of ancient knowledge and the dissemination of new scientific and religious theories, the protagonist discusses: the material, figure, colour, form, energy and eternity of heaven; the motion and the central pole of the heavens; the sun, the moon, the stars; fire; comets and rainbows; lightning, snow and rain; the motion and rest of projectiles in the air; the impulsion of mortars and crossbows; winds and breezes; corrupt airs; the element of water; the birth of the rivers; the rising of the Nile; the extent and saltiness of the sea; the roar and the motion of the water; the motion of projectiles; the creation of islands and mountains, as well as the cause of earthquakes; the genesis, root and colour of the gems, as well as spots of stones; life, food, and the death of the stones; the strength of the magnet to attract iron and its direction toward the Earth's poles; plants; the explanation to be given to certain phenomena of everyday life; semen; the reproduction, nature, respiration and nutrition of fish; the reproduction of birds; the reproduction of bees; the first generation of man; stains contracted by children in the womb; the generation of male and female; parts of monsters; the faces of children covered by larvae; the growth of man; the length of human life; sight; hearing; smell; taste; touch and tickle; the affections of man; God; appearances in the air; oracles; the Sibyls; the possessed; sacred images of the pagans; augurs; the miraculous healing of diseases reported in pagan times; the resurrection of the dead; witchcraft; dreams.