Ancient tides computer?

[zoidberg]

There are lots of Tides Data Tables. Some of them even fit onto a smartphone. How about this....

Update: The Stonehenge “Computer” Just Got Even More Interesting​

Yesterday we looked at the Aubrey Holes as a lunar–eclipse calculator — a machine for predicting when Sun, Moon and nodes line up.

Today we push it one step further.
And suddenly Stonehenge looks even more like the work of a maritime civilisation.

We’ve adapted the model — and it works better for tides than eclipses.​

The same 56-hole system that can spot eclipse seasons also tracks the geometry that controls:

• • spring & neap tides
  • super-tides (perigean spring tides)
  • the 18.6-year nodal tide cycle
  • dangerous surge periods in estuaries
  • windows where long-distance sea travel is safest

This isn’t speculation — it’s physics:

• • Syzygy (Sun–Moon in line) → biggest tides
  • Moon near a node → tides get more extreme
  • Moon at perigee → extreme spring tides
  • Node drifting through its 18.6-year cycle → multi-decade tide shifts

And what does the 56-hole Aubrey computer track?
Syzygy. Nodes. Declination. Long cycles.

Exactly the ingredients of a tidal-risk predictor.

So what did we discover?​

When you map the four-marker system onto modern tidal behaviour:

• • It predicts tidal danger windows better than eclipse windows.
  • It gives advance warning of super-tide eras.
  • It flags seasonal periods when sailing is safe or hazardous.
  • It creates a multi-decadal memory of flood cycles — vital in a wetland world.

In other words:

It works more accurately as a maritime computer than as an eclipse oracle.

Now look at Plato again…​

Plato describes a civilisation that:

• • travelled by boat to all the known world,
  • lived on low-lying islands,
  • relied on precise knowledge of water, tides and weather,
  • and possessed “advanced knowledge” that later peoples lost.

A machine that tracks:

• • tidal extremes,
  • safe sailing seasons,
  • 18.6-year surge cycles,
  • and long-distance navigation windows…

…is exactly the kind of tool a maritime “Atlantis-era” society would create.

If Stonehenge Phase 1 was built in a water-rich Mesolithic landscape (as the archaeology actually shows), then this interpretation makes far more sense than any farming calendar ever did.​

It’s becoming clear:
Stonehenge wasn’t built for wheat.
It was built for water.

And its first phase looks like the world’s oldest tidal navigation computer.

Credit: Robert John Langdon

 

[Alan S]

What has Plato got to do with Stonehenge?
Plato did not know about the relationship between moon and tides or anything about Stonehenge.

 

[Minerva]

Jeewizz. How big a boat do you need to carry your own personal stone henge!?

Think I’ll stick to my wee paper book / phone thank you very much!

 

[neil_s]

I use WXtide!

 

[zoidberg]

Well, has anyone checked yet whether it's accurate?