SURVIVAL FIRE WITH A WATER BOTTLE! - YouTube
Sometimes you find yourself without a way to start a fire, but usually there are plastic bottles of water somewhere to be had, or just go out and fill up an empty water bottle with water in order to use it as a magnifying glass.
Here's a cool video on how to focus the light from the sun through the water bottles onto paper, the young man in the vid uses black paper because it obsorbs light and heat better, while white paper reflects light and heat to some extent.
Sometimes you find yourself without a way to start a fire, but usually there are plastic bottles of water somewhere to be had, or just go out and fill up an empty water bottle with water in order to use it as a magnifying glass.
Here's a cool video on how to focus the light from the sun through the water bottles onto paper, the young man in the vid uses black paper because it obsorbs light and heat better, while white paper reflects light and heat to some extent.