Please read the title frame of each movie for specific information. In this movie we are viewing the Milagro detector pond from the side (below the white line). In order to build up an intuition we are not hitting the pond with a complete EAS, but a toy model instead. The toy model consists of a plane of equally spaced particles of all the same energy, later we will look at full EAS interacting with the Milagro pond. In this movie note in particular the refraction of the showerfront at the pond surface.