Oil, Alchemist's Fire

Source Core Rulebook

You can throw a flask of alchemist's fire as a splash weapon with a range increment of 10 feet.

A direct hit deals 1d6 points of fire damage. Every creature within 5 feet of the point where the flask hits takes 1 point of fire damage from the splash. On the round following a direct hit, the target takes an additional 1d6 points of damage. If desired, the target can use a full-round action to attempt to extinguish the flames before taking this additional damage. Extinguishing the flames requires a DC 15 Reflex save. Rolling on the ground provides the target a +2 bonus on the save. Leaping into a lake or magically extinguishing the flames automatically smothers the fire.