What are those grids of glass in the sidewalk and why are they purple?
I really love these, there was a story about a modern version here: <a href="https://www.youtube.com/watch?v=tJD-D2uLX70" rel="nofollow">https://www.youtube.com/watch?v=tJD-D2uLX70</a> where African's use plastic bottles filled with water as vault lights.