
Peruvian puquios were a “hydraulic system constructed to retrieve water” (2016) - pseudolus
http://www.bbc.com/future/story/20160408-the-ancient-peruvian-mystery-solved-from-space
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mannykannot
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.

~~~
njharman
from the side view here
[https://www.tandfonline.com/doi/full/10.1080/22797254.2018.1...](https://www.tandfonline.com/doi/full/10.1080/22797254.2018.1537684)

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

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twic
They remind me of qanats:

[https://en.wikipedia.org/wiki/Qanat](https://en.wikipedia.org/wiki/Qanat)

~~~
growlist
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.

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petard
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?'

~~~
dogma1138
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.

~~~
memling
> 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](https://en.wikipedia.org/wiki/Pythagorean_theorem#History)

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

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benj111
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')?

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la_fayette
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?

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

[https://www.tandfonline.com/na101/home/literatum/publisher/t...](https://www.tandfonline.com/na101/home/literatum/publisher/tandf/journals/content/tejr20/2019/tejr20.v052.sup01/22797254.2018.1537684/20190322/images/medium/tejr_a_1537684_f0011_oc.jpg)

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.

~~~
la_fayette
Thanks for your explanation!

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trebligdivad
They remind me of Indian Step wells.

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aaron695
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...](https://www.tandfonline.com/doi/full/10.1080/22797254.2018.1537684)

Pics of the tunnel

[http://people.umass.edu/proulx/online_pubs/Zurich_Puquios_re...](http://people.umass.edu/proulx/online_pubs/Zurich_Puquios_revised_small.pdf)

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hobs
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"

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pumanoir
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.

~~~
hobs
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.

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jaclaz
>8 April 2016

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

[2016]

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

