This DIY lightbulb is incredibly practical
To survive in the wild, the power of nature needs to be harnessed. This means taking advantage of natural resources such as creeks, prey, vegetation, and even sunlight. Shelters can be very dark, even during the day, but there is a way to use the sun to brighten the space.
All that’s needed is a transparent bottle of any size filled with water. Then, simply cut a hole into the roof of your shelter and stick the bottle through. A process called diffraction will make it so that the light spreads further.