The Twinlamp, originally produced for use on 5th Avenue at the dawn of the electrified lamppost era in the 1890s, originally had a different design (the mast of one of those originals can still be seen at the NE corner of 5th Avenue and East 23rd Street at Madison Square). Later, a modified design that set the template for subsequent Twinlamps appeared on 5th Avenue, and by the time 5th Avenue’s Twins were torn down in 1965, it was about 50/50 between the originals and the modifieds.
Both the original and modified Twin designs can be seen scattered around town throughout the 20th Century. The Twin was a favored design for roads with a separated median, and was used on roads that had them such as Queens Boulevard.
By the late 20th and early 21st Century, older Twins had become rare and could be found on occasion on 5th Avenue and City Hall Park, with lone wolves on 6th Avenue and Amsterdam Avenue uptown (the latter a monumental Twin that was only used at major intersections).
About 15 years ago, the DOT installed a set of retro-Twins on West 41st and 42nd and 6th Avenue around Bryant Park and the NY Public Library. They’re about an identical maps to the Twins Mach II that populated 5th Avenue and other major roads. Unlike other retro designs the City has been sparing in their use of Twins, though “monumental” versions of them with more wrought iron work has been installed at City Hall Park.
When I was over there the other day, I noticed that the “new” Twins had been “pimped out” with sets of mini-spotlights that supply decorative lighting on the NYPL building at night.
This one likely has an addition meant to facilitate cellphone calls. The red button atop the shaft
indicates (subtly) that there is a fire alarm nearby. is a photocell that turns the map on at dusk.