Quickfire 101 is a series of short videos showing you lots of interesting ways to make fire. NEW VIDEOS EVERY TUESDAY. How to start a fire with a tea bag. And a vacuum. So yes, I suck. But just this once.To make a parabolic mirror for solar concentration, we use a basic principle of physics. According to Pascal's law, the pressure within a closed container is the same at all points within that container. This serves to pull our film down into a parabolic shape.