

Dujiangyan irrigation system - bane
https://en.wikipedia.org/wiki/Du_Jiang_Yan_Irrigation_System

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austinz
I always considered it fascinating how so many of China's cultural heroes were
people who built great works and disseminated knowledge. (Not that Chinese
mythology is necessarily unique in this manner, of course.)

\- Shennong, who invented agriculture.

\- Cangjie, who invented Chinese characters.

\- Yao, Shun, and Yu, who tamed the river floods and irrigated the fields.

~~~
HowardMei
Philosophic Taoism introduces Dao, the origin and derivatives of the essence
of nature, its laws and forms, on top of which the Taoist religion developed a
complete methodology for normal people to ascend into heaven by practicing
introductory transcending courses and eating natural/artificial elixirs.

The ultimate stage of ascended beings will be Tao itself, the advanced stage
is celestial being, and the intermediate stage is god, and the beginning stage
is 'trueman'.

Celestial beings have freedom to create new rules/universes with certain
backfiring possibility which may cease their own existence. Normally they
don't care about earth and human beings except for promoting new gods. Gods
are anthropomorphic and every one has a job. They either enforce specific
rules or govern certain domains to maintain the human world. Truemen are long
lived human beings and they can self-educate themselves ascending to be new
gods or destroyed by Tao if they fail to purify themselves.

Therefore, Taoism has two ways of creating anthropomorphic gods:
promoted/guided by Celestial beings or self-help to ascend.

The first way is for great inventors and heroes etc. The second way is for
Taoist priests and emperors, but neither of them succeeded.

LoL

In China history, many famous emperors were poisoned by mercury because Taoist
alchemists believed it's an essential ingredient for any elixir (on purpose?)
;D

------
chenster
A map of the irrigation system
[http://www.travelchinaguide.com/images/map/sichuan/dujiangya...](http://www.travelchinaguide.com/images/map/sichuan/dujiangyan-
irrigation-project.jpg)

Being there many times when I was living in Sichuan province. Its significance
though never really struck me util I was in adulthood. It's indeed a
magnificent project considering it was built more than 2000 years ago. It is
still in use today!

~~~
muxxa
On OpenStreetMap:
[http://www.openstreetmap.org/#map=15/30.9966/103.6092&layers...](http://www.openstreetmap.org/#map=15/30.9966/103.6092&layers=C)

Good to zoom out and see the context of the mountains vs. plain.

------
meric
"Modern studies suggest that, on purchasing power parity basis, one tael of
silver was worth about 4130 RMB (modern Chinese yuan) in the early Tang
Dynasty, 2065 RMB in the late Tang Dynasty, and 660.8 RMB in the mid Ming
Dynasty[citation needed]." [1]

So taking the nearest estimated value of a "tael", 100,000 taels of silver *
4130 CNY / 6 CNYUSD, the irrigation system costed around USD $68m in today's
dollars to build, back during the Qin dynasty.

There were an estimate of 20 million people living in Qin china.[2]

By the time of the Han dynasty, just 200 years later, the population tripled
to almost 60 million [3].

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

[2]
[http://en.wikipedia.org/wiki/Qin_dynasty](http://en.wikipedia.org/wiki/Qin_dynasty)

[3]
[http://en.wikipedia.org/wiki/Han_dynasty](http://en.wikipedia.org/wiki/Han_dynasty)

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azernik
Very cool:

    
    
      Cutting the channel proved to be a far greater problem as
      the tools available to Li Bing at the time, prior to the
      invention of gunpowder, were unable to penetrate the hard
      rock of the mountain so he used a combination of fire and
      water to heat and cool the rocks until they cracked and
      could be removed.

~~~
arbuge
This is the same method believed to have been used by Hannibal's army when it
crossed the Alps on its way to Rome: [http://en.wikipedia.org/wiki/Fire-
setting](http://en.wikipedia.org/wiki/Fire-setting)

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huxley
Ancient irrigation systems are often the ignored wonders of the world.

My favourite is the Zarch Qanat, which is about 3000 years old and has a
tunnel into the water table which is about 71 kilometres long with over 2000
vertical shafts into the tunnel.

[http://www.livius.org/q/qanat/qanat.html](http://www.livius.org/q/qanat/qanat.html)

[http://en.wikipedia.org/wiki/Traditional_water_sources_of_Pe...](http://en.wikipedia.org/wiki/Traditional_water_sources_of_Persian_antiquity)

------
gaoshan
Dujiangyan is astonishing to see in person. The scale of such an ancient
project is mind boggling. Sadly, much of the surrounding area was destroyed in
the 2008 earthquake as the epicenter was very nearby.

------
PhrosTT
There's a good documentary on this:
[https://www.youtube.com/watch?v=P4FRO1eYdgQ](https://www.youtube.com/watch?v=P4FRO1eYdgQ)

~~~
chenster
The correct ones:

[https://www.youtube.com/watch?v=KKkwb00MeEM](https://www.youtube.com/watch?v=KKkwb00MeEM)

[https://www.youtube.com/watch?v=dW2NJwH2fpI](https://www.youtube.com/watch?v=dW2NJwH2fpI)

