Cities 101: What are the Little Glass Circles in the Sidewalks of Soho?

Small circular glass bulbs dot the sidewalks of Soho–are they chic street stylings or art? The glass circles are actually remnants of Soho’s industrial past, a signifier of the original factory function of the buildings. The glass bulbs are actually tiny windows–called “vault lights” or deadlights–to allow sunlight into the basement factories before the introduction of electricity.

They are inlaid onto a metal frame on the ground but many deadlights have been filled in with a variety of materials–from concrete to stone– as they were viewed as a hazard. Many still remain as glass, however, and you can see some at the intersection of Greene Street and Canal Street.

According to one of our favorite books, Secret New York – An Unusual Guide, the signs that alert pedestrians to “hollow sidewalks,” is not an unfounded warning: “Sidewalks have caved in before. One of the uglier details of the 1911 fire at the Triangle Shirtwaist Factory–the third most lethal disaster in New York history–was bodies falling from the burning building, and right through the ground to the basement.”

Next time you are walking the streets of Soho, be sure to note those little glass circles that often adorn the sidewalks!

Soho is a fascinating neighborhood that has drastically evolved over the 20th century. Be sure to check out our article on the history of Crosby Street–which borders the Soho-Nolita border–to understand this history!

Read more from our Cities 101 series about how stuff works in the city. Get in touch with the author @spencercnyc.