In ancient time before the invention of metal and clay pots. Humans had been boiling water in large cup shaped leaves. We know this is old method of boiling water but for fun and learning how it works we will boil water in a bag made out of paper.
- Make a simple cup shaped paper bag. Keep the bottom area of the bag larger than the area of the fire of your gas stove
- Put your bag on stove and pour some water in it. Start fire gently and keep its flame level lower than the corner and sides of your bag. Otherwise sides of your bag may burnout. Wait until water starts to boil. If you have house hold thermometer use it to check water temperature.
Paper has ability to absorb water when you pour water in your paper bag, it absorbs some water which prevents it from burning and fire keeps the paper dry. In this way water that becomes hot goes to surface and cold water takes its place. This process continues as long as your bag has water.