Hundreds of these reverse-crooked, simple posts containing a parallelogramatical 4-paned glass surface light the streets of Society Hill near downtown Philadelphia. They are named “Franklin lights” because they were inspired by Benjamin Franklin’s street lighting idea in the colonial era. Noticing that the glass luminaires on oil lamps found in London and Paris had to be frequently cleaned because of accumulating soot, Franklin proposed a 4-paned surface with a funnel above and small holes or crevices admitting air below. This allowed the glass to stay clear.
Like most NYC lamps, Franklin lights bear the date of installation on the base, 1968 in this case.