Peruvian puquios were a “hydraulic system constructed to retrieve water” (2016) | Hacker News Reader

Peruvian puquios were a “hydraulic system constructed to retrieve water” (2016)

bbc.com

93 pointspseudolus27 comments

I curious as to whether the spiraling ramp helps direct the wind through the tunnels in some way, or if it is for some other purpose, such as to help remove construction debris.

Somewhat tangentially, I recall reading, years ago, about an ingenious pre-columbian self-regulating aqueduct in northern Peru. It had an asymmetrical constriction where a vortex formed if the flow reached a certain speed, restricting the flow and causing a hydraulic jump that directed flood water into an overflow channel.

from the side view here https://www.tandfonline.com/doi/full/10.1080/22797254.2018.1...

It's clear they follow the "funnel" shape. Optimized for laminar (air) flow. Not for hauling (which you'd want a fixed slope for.

> I curious as to whether the spiraling ramp helps direct the wind through the tunnels in some way

To me it looks like it channels wind coming from any direction down the spiral. At the bottom it presumably channels the air current to push the water in one direction.

They remind me of qanats:

https://en.wikipedia.org/wiki/Qanat

There was a documentary about these on the BBC maybe 15 years ago, part of a series the theme of which was dangerous places or similar. The presenter walked the length of a Qanat and seemed genuinely worried by the poor state of it in parts, which was unintentionally amusing, but he did make it out in one piece in the end. Can't find it on the web sadly.

Yes, these are independently invented examples of qanats.

The geometry of the access holes resulting in wind-powered water motion is unique.

I wonder how such technology develops since it is not something you discover by accident. Like 'Hey let's dig a whole there and see what happens?'

Probably was just the product of leveraging the observations and knowledge their society had at the time to produce a novel solution to a region-specific problem. Humans don't seem to have gotten any more or less intelligent than our ancient predecessors, those of us in this particular time period were just were born with a different and relatively more advanced set of tools. If you constrain the set of possible methods to achieve a solution, you usually increase the creativity required to achieve that solution.

I've always have thought it is the result of diversions developed by very smart and curious people.

Don’t underestimate unintentiofnal lucky accidents and coincidence.

Many cultures were burying things such as fruit, fish and cattle in fields before planting the seeds and burning fields after the harvest as a form of a religious offering without understanding what was going on, on a chemical level in the soil.

No one would think of burning “sky rocks” to make daggers and swords out of them either in a rational manner. But it makes sense that they would do so in some odd religious ritual.

Pretty much every initial technological advancement in human history was likely driven by an irrational thought completely unrelated to what would be achieved in the end before the scientific method was developed.

> Pretty much every initial technological advancement in human history was likely driven by an irrational thought completely unrelated to what would be achieved in the end before the scientific method was developed.

This strikes me as highly unlikely, considering how recently the scientific method was formalized.

It's hard to imagine, for example, that the Babylonians' or Egyptians' use of the Pythagorean theorem[1] was irrational, even though it undoubtedly had mystical and religious overtones to it. (The idea of separating science and religion as such is a relatively modern invention. The medievals called theology "queen of the sciences," for example,[2] perhaps due to their belief that rational study of the universe required a rational cause of the universe.)

[1]: https://en.wikipedia.org/wiki/Pythagorean_theorem#History

[2]: https://en.wikipedia.org/wiki/Theology#As_an_academic_discip...

Those rituals evolved in the first place because they were effective. Religion only becomes relevant when you look at the explanation of why it works. They believed that the gods would take those gifts as offerings. If some ritual didn't work, then it seems that ritual couldn't convince the gods to make the plants grow better, so they tried something different. Sure, a scientific explanation might help with finding out which things work and which don't, but in theory, trial and error doesn't need a proper explanation for the phenomenon.

It's not clear to me that ancient smiths making blades out of meteoric iron were aware of the connection between streak of light in the sky phenomena and the iron/nickel stones they found on the ground and discovered to be suitable for making blades.

Most meteoric iron probably fell long before it was used. For instance the Cape York meteorite used by the Inuit for making blades fell 10,000 years ago. That's many thousands of years before the Inuit are believed to be in Greenland.

Trying things based on existing understandings leads to discovery, but so does trying things "just because." It's worth pointing out that the former often involves an existing understanding that isn't actually correct.

Both activities are useful, and they're both rational because they're useful. (Obviously you can't try out every possible thing "just because," so formalized science has to prioritize.)

Can someone explain why they didn't build the canal on an incline? Do these holes have other uses to make them worthwhile (wells, 'manholes')?

If you try to dig a hole in the ground, without machinery like a ground drill just something like a shovel, it is only natural that one requires to extend the diameter of the whole? It is like one tries to dig a hole in the sand. So it seems like these people just went stepwise, that digging deeper was possible. Would they had any other possibility to dig a deep hole into the ground?

Not sure if this will happily link directly without a referer but here goes:

https://www.tandfonline.com/na101/home/literatum/publisher/t...

The funnel shape of the ramp appears very deliberate, and not the kind of thing you'd naturally arrive at digging in sandy soil.

The agressive slope towards the botttom would be especially frustrating. If the ground is very loose and wants to crumble and cave in like sand, getting the steep part of the ramp to hold its shape all these years required a lot of deliberate effort.

At first I thought maybe it was just a spiral ramp for the laborers, since there's a lot of material to remove manually making such holes in general. But that agressive slope towards the end is not doing them any favors. It really does appear to be engineered with fluids in mind.

Thanks for your explanation!

They remind me of Indian Step wells.

Sure, it's not a easy way to walk to the water and clean the tunnel, it's an atmospheric pump.

Common in other cultures -

https://www.tandfonline.com/doi/full/10.1080/22797254.2018.1...

Pics of the tunnel

http://people.umass.edu/proulx/online_pubs/Zurich_Puquios_re...

I do not understand how the following sentences can be coherent in the same article about why these wells exist -

"Could only be solved using space technology"

"Some of the wells are still operating today"

It is irritating, especially as the article is not clear about what contribution space technology made. It seems that satellite images revealed that the system was larger and more sophisticated than known beforehand, and, given that the images are available, it is presumably at least a much cheaper and faster way to find this out than an extensive ground survey.

Poor wording. It is not that using wing tunnel pressure to pump water is space tech. But that only seen from space they could map it to the civilization for context.

If tomorrow all humans and humans artifacts disappear except the great china wall, an alien will be very confused why it exists, not how it was built.

Happens a lot on articles about non-western civilizations technological advancements. The writers -of this articles- assume that western technology is the best/most advanced (most probably without malice) and the others' are just cute or magical.

Right, and if some secondary source called out the fact that they are still in use and these guys are idiots then at least the original article would have made the sin of omission, and not the sin of outright contradicting yourself.

>8 April 2016

>This story is featured in BBC Future’s “Best of 2016” collection.

[2016]

The admins asked us to email this kind of thing to them using the footer Contact link, which I’ll do now.

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