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What are those grids of glass in the sidewalk and why are they purple?

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Re: What are those grids of glass in the sidewalk and why are they purple?

#52
> Vault lights were used to light some of New York City's first subway stations and were placed in the ground of the opulent passenger concourse in the city's original Pennsylvania Station.

I will never get my head around the fact that the old Pennsylvania Station was destroyed. It must be one of the biggest mistakes in urban development of the 20th century.

> Another architectural critic, Ada Louise Huxtable, wrote in The New York Times in 1963: "The tragedy is that our own times not only could not produce such a building, but cannot even maintain it." [0]

https://upload.wikimedia.org/wikipedia/commons/6/60/Penn_Sta...

https://upload.wikimedia.org/wikipedia/commons/3/39/NYP_LOC5...

https://upload.wikimedia.org/wikipedia/commons/thumb/d/d9/So...

https://upload.wikimedia.org/wikipedia/commons/f/f8/The_New_...

https://live.staticflickr.com/5085/5383028384_a22f3605e4_b.j...

https://static01.nyt.com/images/2019/04/24/lens/24pennnstati...

[0] https://en.wikipedia.org/wiki/Pennsylvania_Station_(1910%E2%...

Re: What are those grids of glass in the sidewalk and why are they purple?

#53

Lots in London, and many very old - but I've never spotted purple ones.

Well, the color being due to exposition of the prisms to UV radiation, it will take a lot longer to reach the purple tint in London than in California.

Re: What are those grids of glass in the sidewalk and why are they purple?

#54
post #47
post #26

Earlier quoted context omitted.

That must be a western concept. On the east coast it's common for sidewalks to be owned by the landowner yet have to remain unencumbered for the public right of way. Some owners find out the hard way that they are also responsible for maintaining the sidewalk when the city hits them with a notice.

> Some owners find out the hard way that they are also responsible for maintaining the sidewalk when the city hits them with a notice. I live in Phoenix; in my neighborhood it's basically the same way. City comes around, tears up the sidewalk to fix something (water main or such) - and you the homeowner are responsible for fixing the sidewalk. Yay. About all the city will do is put some asphalt over the bare dirt, bu…

> I live in Phoenix; in my neighborhood it's basically the same way. City comes around, tears up the sidewalk to fix something (water main or such) - and you the homeowner are responsible for fixing the sidewalk. Yay.

What in the holy hell? That's insane and ridiculous. Is this for both residential and commercial? (I could understand the latter slightly more.)

Sounds like a great way to piss off your citizens by cutting a very small corner in what is probably already an expensive endeavor.

Re: What are those grids of glass in the sidewalk and why are they purple?

#55
post #7

These are ubiquitous in London

Notably the ones in Crystal Palace [1] which are above an old underground toilet, now converted into someone's house! [2] I guess — in this case, at least — the fogging-up of the glass is actually a privacy feature.

[1] http://1.bp.blogspot.com/-SuRJ4LN5LhQ/T3GQS8rUN9I/AAAAAAAAAM...

[2] http://crystalpalacetoilets.blogspot.com/

Re: What are those grids of glass in the sidewalk and why are they purple?

#56

Denver has these, you can see them on Larimer and Market street in LoDo. Around the 1890s, the locals dug out a series of tunnels through the city. The snows would come in and people would just go underground for a few days for business. There was a bar that closed about a year ago called the Blake Street Vault—it used to be a bank—and if you asked they would take you into the basement to see the vault and the dumbwa…

I've got some friends in Minneapolis that November - ~May don't leave the skyway system. Seems similar, but connects buildings at the 2nd story instead of underground.

http://www.skywaymyway.com/

Re: What are those grids of glass in the sidewalk and why are they purple?

#57

Lots in London, and many very old - but I've never spotted purple ones.

Well, the color being due to exposition of the prisms to UV radiation, it will take a lot longer to reach the purple tint in London than in California.

About a million years

Re: What are those grids of glass in the sidewalk and why are they purple?

#58
post #11

This is interesting, but raises a question. The article mentions: In San Francisco, vault lights are mostly used to illuminate sub-sidewalk basements — ie. basements that extend under the sidewalk. How does this work, legally? Where I live, sidewalks are property of the city (or the HOA, in some cases), and I'd presume the same in SF. Does the title of the sidewalk-adjacent property allow you to excavate N feet beyon…

I read somewhere (Atlas Obscura?) that there are some hollow sidewalks in NYC, and the sidewalk-adjacent property owners pay for the real estate underneath. To get around this, some owners have sealed off access from their building to the sub-sidewalk spaces, leaving closed off, empty chambers.

Re: What are those grids of glass in the sidewalk and why are they purple?

#59
post #52

> Vault lights were used to light some of New York City's first subway stations and were placed in the ground of the opulent passenger concourse in the city's original Pennsylvania Station. I will never get my head around the fact that the old Pennsylvania Station was destroyed. It must be one of the biggest mistakes in urban development of the 20th century. > Another architectural critic, Ada Louise Huxtable, wrote…

[deleted]

Re: What are those grids of glass in the sidewalk and why are they purple?

#60
post #52

> Vault lights were used to light some of New York City's first subway stations and were placed in the ground of the opulent passenger concourse in the city's original Pennsylvania Station. I will never get my head around the fact that the old Pennsylvania Station was destroyed. It must be one of the biggest mistakes in urban development of the 20th century. > Another architectural critic, Ada Louise Huxtable, wrote…

Interesting enough the glass floor was never removed during the demolition of the original Penn Station and can still be seen from the track level. Of course the floor has been tiled over and no longer functions as a light source, but it serves as a hidden reminder of the old Penn Station.

https://ny.curbed.com/2018/10/23/18009496/penn-station-new-y...

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