You've got Avebury down for earth and water.

As water though, 'ab' or 'av' as in 'avon' or 'abhainn' is a water word/element so perhaps Avebury could be water?

And perhaps Marden is 'air'? The 'ar' bit is similar to 'air' and in galic is 'adhar' which is the same word really.

Sounds good to me.

Stonehenge = Sun = Fire
Avebury = Ab/Av = Water
Marden = Ahdar = Air

But where = Earth?

The Welsh for earth appears to be 'daear' and is used in a variety of compounds.

http://welsh-dictionary.ac.uk/gpc/gpc.html

Would Durrington Walls fit the bill?

Are there other places with similar names in the area? For that matter 'area' is almost an anagram of 'daear'.

I wonder if there is any connection there.

Dwelly has 'uir' 'uirach', 'cre' and others as well as the usual 'talamh' (pronounced 'talav' or possibly 'talloo')

The first two would fit with Durrington. Are there any others with 'cre' or 'tal' connections?

Dorchester Henges?

Four elements, is of course, just an assumption.

If each henge had an elemental role, perhaps we should be looking for seven or more elements?

Some say there are 115 elements others say 118 that we know of.

http://education.jlab.org/qa/element.html

Why would henges serve to illustrate a particular element?

If we combine certain henges would the result be a new element?

Is water an element anyway? Isn't it the combination of hydrogen and oxygen elements?

If we stick to the basic 'four elements' perhaps the purpose of each henge could be to inform the locals of changes within that particular elemental makeup? Some henges could be designed to give information on the sun, others on the stars in general or particular, others to do with the rotation or progression of the earth and yet others could be looking at changes in water patterns?

After the catastrophe of the ice age and whatever caused it it could be that people wanted to find a means of forecasting whether or when it was going to happen again.

I wondered who would be the first to mention the periodic table. My fault for not making it clearer that I meant the "classical" ideas of how many elements there are, not this "new fangled" version.

I am the only person in the world who thinks the Periodic Table is wrong.

You're not a forgetful Daily Mail reader by any chance?
http://www.dailymail.co.uk/sciencetech/ ... place.html

Or, presumably, you mean it's "wrong" in a more fundamental way than the Daily Mail is suggesting?

If you read carefully, nobody is actually challenging the validity of the Periodic Table (as I do). The classic sign that it is all wrong can be found in the first para of the Mail report

It has been a key part school chemistry lessons for more than a century, but now the periodic table may need to be redrawn after scientists found a rare element may be very different from originally thought.

As I say in THOBR re Linnaean Classification and Darwinian Evolution, not too much store should be given to systems that allow you to change the system every time something anomalous comes along. That get-out clause makes the paradigm immortal. Right or wrong. The actual truth (ie the next paradigm when we've overthrown the Periodic Table) is hinted at in this para:

In a paper published in the journal Foundations of Chemistry last month, he said: 'Though there are many misconceptions concerning the nature and function of the periodic law and table, perhaps the most prevalent among modern chemists is the belief that the periodic table is nothing more than an electron configuration table. 'While there is certainly a significant correlation between electron configurations and chemical periodicity, the correlation is far from perfect.