18 - Book 6, pt. 3 - About the temperature of waters. About magnets and why metals are attracted to them. About the origin and cause of diseases. Description of the plague that depopulated Athens during the Peloponnesian war.

Summary: 18 - Book 6, pt. 3 - About the temperature of waters. About magnets and why metals are attracted to them. About the origin and cause of diseases. Description of the plague that depopulated Athens during the Peloponnesian war.