Urban CAT Scan

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

The London-based ScanLab Projects, featured here many times before, have completed a new commission, this time from the British Postal Museum & Archive, to document the so-called "Mail Rail," a network of underground tunnels that opened back in 1927.

As Subterranea Britannica explains, the tunnels were initially conceived as a system of pneumatic package-delivery tubes, an "atmospheric railway," as it was rather fantastically described at the time, "by which a stationary steam engine would drive a large fan which could suck air out of an air tight tube and draw the vehicle towards it or blow air to push them away."

That "vehicle" would have been a semi-autonomous wheeled cart bearing parcels for residents of Greater London.

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

Alas, but unsurprisingly, this vision of an air-powered subterranean communication system for a vast metropolis of many millions of residents was replaced by a rail-based one, with narrow, packed-heavy cars running a system of tracks beneath the London streets.

Thus the Mail Rail system was born.

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

While the story of the system itself is fascinating, it has also been told elsewhere.

The aforementioned Subterranea Britannica is a perfect place to start, but urban explorers have also gained entrance for narrative purposes of their own, including the long write-up over at Placehacking.

That link includes the incredible detail that, "on Halloween night 2010, ravers took over a massive derelict Post Office building in the city and threw an illegal party of epic proportions. When pictures from the party emerged, we were astonished to find that a few of them looked to be of a tiny rail system somehow accessed from the building."

Surely, this should be the setting for a new novel: some huge and illegal party in an abandoned building at an otherwise undisclosed location in the city results in people breaking into or discovering an otherwise forgotten, literally underground network, alcohol-blurred photographs of which are later recognized as having unique urban importance.

Something is down there, the hungover viewers of these photographs quickly realize, something vague and hazily glimpsed in the unlit background of some selfies snapped at a rave.

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

This would all be part of the general mysticism of infrastructure that I hinted at in an earlier post, the idea that the peripheral networks through which the city actually functions lie in wait, secretly connecting things from below or wrapping, Ouroborus-like, around us on the edges of things.

These systems are the Matrix, we might say in modern mythological terms, or the room where Zeus moves statues of us all around on chessboards: an invisible realm of tacit control and influence that we've come to know unimaginatively as nothing but infrastructure. But infrastructure is now the backstage pass, the esoteric world behind the curtain.

In any case, with this handful of party pictures in hand, a group of London explorers tried to infiltrate the system.

After hours of exploration, we finally found what we thought might be a freshly bricked up wall into the mythical Mail Rail the partygoers had inadvertently found... We went back to the car and discussed the possibility of chiselling the brick out. We decided that, given how soon it was after the party, the place was too hot to do that just now and we walked away, vowing to try again in a couple of months.

It took some time—but, eventually, it worked.

They found the tunnels.

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

The complete write-up over at Placehacking is worth the read for the rest of that particular story.

But ScanLab now enter the frame as documentarians of a different sort, with a laser-assisted glimpse of this underground space down to millimetric details.

Their 3D point clouds afford a whole new form of representation, a kind of volumetric photography that cuts through streets and walls to reveal the full spatial nature of the places on display.

The incredible teaser video, pieced together from 223 different laser scanning sessions, reveals this with dramatic effect, featuring a virtual camera that smoothly passes beneath the street like a swimmer through the waves of the ocean.



As the British Postal Museum & Archive explains, the goal of getting ScanLab Projects down into their tunnels was "to form a digital model from which any number of future interactive, visual, animated and immersive experiences can be created."

In other words, it was a museological project: the digital preservation of an urban underworld that few people—Placehacking's write-up aside—have actually seen.

For example, the Museum writes, the resulting laser-generated 3D point clouds might "enable a full 3D walkthrough of hidden parts of the network or an app that enables layers to be peeled away to see the original industrial detail beneath."

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

Unpeeling the urban onion has never been so gorgeous as we leap through walls, peer upward through semi-transparent streets, and see signs hanging in mid-air from both sides simultaneously.

[Image: By ScanLab Projects, with permission from the British Postal Museum & Archive].

Tunnels become weird ropey knots like smoke rings looped beneath the city as the facades of houses take on the appearance of old ghosts, remnants of another era gazing down at the flickering of other dimensions previously lost in the darkness below.

(Thanks again to the British Postal Museum & Archive for permission to post the images).