Tiled tunnel under Belgian river "staggeringly monotonous"


Originally published at: https://boingboing.net/2018/05/11/tiled-tunnel-under-belgian-riv.html


With the right tile nobody would notice:



Know what would break up the monotony? A nice little kid on a Big Wheel. That’d do the trick.


Can we get some 70’s SciFi spinning lights in here?





You mean diameter, or radius of curvature? Nobody would ever build a tunnel so enormous the walls appear flat - what would be the purpose? You could fly the Starship Enterprise through such a tunnel, but demand for that is pretty slim.

A short tunnel could be imperceptibly curved - in fact, I’ll bet some of them are. Maybe all of them are, if you got out your micrometer calipers. I would imagine the answer is a function of the length of the tunnel. In Minecraft the answer would be 128 meters, but there are no curved things at all in Minecraft.


Imagine the highlight articles: “This tunnel beneath Antwerp’s gone PLAID!!!”


Of course there is a REASON that wooden escalators are rare these days…


If the moon had a flat surface, would it seem flat flat to someone standing on it?


This is my own reminiscence :


It could definitely stand to have some art here and there.


Many of the tunnels under Montreal are similarly monotonous and long.


It would be greatly improved by the crooked installation of exactly one tile. The excitement would be unbearable.


The latter! The curvature of the circle, not the curvature of the walls. Like a particle accellerator.


Fine, you cover the costs of all the lawsuits from cyclists with OCD.


I figure that a well-lit circular tunnel (especially with clear geometrical qualities like the lighting strip), would indeed have to be of celestial dimensions to fool a human observer with good sight into thinking it was straight. But I’m hoping that a dimly lit one with slightly irregular walls (such as ones lined with full bookshelves) could be quite small. I’m hoping to get away with 10 kilometers in diameter, but that might be too much to hope for.

1km is ideal, but then it would have to be so dimly lit that even a few meters of visibility might reveal the curvature. Dim lighting is nice in libraries, though.


It does not take a very powerful telescope to see the curvature of the Earth along a canal.


If you want a frighteningly non-monotonous bike tunnel, the Paw Paw tunnel on the C & O Canal towpath is just the ticket, with no lights and a very uneven surface on the narrow, barely railing-ed ledge path next to the canal. (Tripadvisor pic).


I have gone through this tunnel a few times; the monotony is broken up by the mild unease, and the occasional puddle.


Ah, that makes more sense!

I suspect it would depend more on the atmosphere than any other factor. If there’s a lot of haze and visibility is limited to something like 20 meters you could get away with a much tighter curve than if visibility out to the horizon distance is possible. “Tight” in such a case would still be pretty big, but in the first case you just need to fool somebody into thinking 40 meters of tunnel is straight, in the second you need to get them thinking something like 20km worth of tunnel is straight.

I don’t think the books alone would affect your question, but if the shelves were crooked and the book placement was chaotic, it might make it harder to detect curvature. The human eye / mind system is really really good at judging whether lines are parallel / converge into the distance, so the presence of such cues as a regularly tiled wall in tunnel would likely be a big help in determining whether it is straight or not.

It might be possible to hijack that perception and create the illusion of a straight tunnel by using slightly smaller books / shelves on the inside wall of the curve…