Wash the jar with hot water and lemon washing up liquid, leave to dry.
Fill with approx 100g of glass beads, aquarium gravel, or screwed up balls of aluminum foil.
You can also cover the neck with foil and poke a hole with the stick to hold it upright. I put mine in a steel balti dish to catch the ash.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.