Here’s a dayburning General Electric M-400 I found during a walk in Hoboken. These lamps shine a greenish-white when fully illuminated at night, but during the day, or when first coming on, they’re distinctly green. Also, they emit an unmistakable buzz when first coming on at dusk, too. The light comes from mercury vapor.
The GE M-400s first appeared on NYC streets in 1958 in concert with the first Donald Deskey post to appear, at Broadway and Murray Street across from City Hall Park. They didn’t become widespread, though, until 1962 when they began to make major inroads on the Westinghouse AK-10 cuplight.
Westinghouse was not to be defeated so easily. Their own mercury vapor lamp, the OV-25, part of their OV series, battled tooth and nail with the GE-M400 for supremacy on NYC streets until 1968. That year, GE upped the ante with the first bright yellow sodium vapor lamp. Westinghouse followed suit with its own model. Other makes also followed with sodium lamps onto NYC streets over the next 30 years.
Cooper OVD completely replaced every other make on NYC streets in 2009 (the company has since discontinued the product), but NYC is currently replacing them with various makes and models of harsh white Light Emitting Diode lamps, which are supposedly cheaper to maintain. Your move, General Electric…
“Comment as you see fit.” firstname.lastname@example.org