Trade Secrets

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Re: Trade Secrets

Postby Mick Harper » 9:18 pm

Extract Four

Great Circles are any circumference of the earth. The equator for instance is a Great Circle but no other line of latitude is; all lines of longitude are Great Circles. It is possible to draw a Great Circle line between any two points on the earth's surface and that will be the shortest distance between the two points. However this 'Great Circle route' is not necessarily the 'best' route. Here is an illustration of why:

For your Sunday walk this week you decide on a hike across the Sussex Downs, from Duckinfield to Cuckoosmere, a roughly east to west stroll of some twenty miles. There are no obvious paths and you can walk anywhere but, since you have a train home to catch at Cuckoosmere, you decide on a direct route, following a compass bearing taken from your OS map.

You are accompanied by your twin-brother (note 1) who walks at exactly the same pace as you do. By an odd working of a local space-time wormhole, this twin brother of yours happens to have been born c 1000 BC and to be a native of, or at any rate familiar with, the South Downs of Sussex. Despite the gulf in your interests he agrees that a Duckinfield to Cuckoosmere walk would be agreeable so the two of you set off companiably enough.

After a few miles though conversation gets a little strained because you have become separated by several yards. When you ask your brother why he points to something vague on the horizon, “The route to Cuckoosmere.” Not so, you say, the map clearly shows that the route is this way. Your twin shrugs and since you share an obstinacy gene, your respective journeys continue to diverge.

Irritatingly, your twin seems to be ever-so-slightly forging ahead of you and, infuriatingly, he actually arrives at Cuckoosmere a little ahead of you. After dispatching the little tick back down the wormhole you trace out his route on your map. Your own route is a straight line, his is slightly bowed and follows a path slightly to the north of yours.


[Diagram of the two Duckinfield to Cusckoosmere routes.]

It turns out that his was the Great Circle route, the shortest route between any two points on the earth’s surface, whereas yours was a compass bearing which (unless it is exactly north-south) never is the shortest route. It looks straight on the map but this is because a map is a two-dimensional rendering of a three-dimensional object. On a globe it would be your twin's journey that is the direct line.

But how did your primitive twin know about Great Circles, familiarity with which would appear to imply a somewhat sophisticated grasp of Global geometry? The answer of course is that he had no such knowledge, he was merely following the line-of-sight route between Duckinfield and Cuckoosmere. Or rather he was following the line-of-sight markers that marked out the line-of-sight route. This is as automatically a Great Circle route as your compass bearing and map route isn’t.

But why is this important for our purposes? If we summon up the wormhole again and get an archaeologist a thousand year into the future to have a look at cropmarks (or whatever they do a thousand years hence) in order to tell us about routes between Duckinfield and Cuckoosmere, he will likely tell us:

The crop marks indicate there are two routes.

1. This one is clearly following the ‘map’n’compass route’ and is therefore relatively modern ie after maps and compasses c 1000 AD. There is no road so the route is presumably recreational ie after c 1900 AD. There will be no other evidence in the landscape though there might be historical evidence.

2. This is the Great Circle route and therefore relatively ancient following line-of-sight markings in the countryside. These markers, or the evidence for same, ought still to be there. It is highly unlikely there will be any historical evidence
.

(1) Given the overwhelming gender of British recreational walkers more likely ‘twin-sister’ but we will stick with convention.
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Re: Trade Secrets

Postby Mick Harper » 9:20 pm

Extract Five

The Great Circle line between Burgh Island and Marseille might be of interest to an airplane pilot but how might it be relevant to a prehistoric trader? It is all very well claiming that line-of-sight routes might be ‘mapped out’ on land but how could the same possibly be done at sea?

The answer is, “Rather straightforwardly and the evidence is still there for all to see.” We know where to look for that evidence since the sea section of the Great Circle route is relatively short.

Image

As we know, the British end of the route is a causewayed tidal island, Burgh Island, and that Burgh Island is one of only two causewayed tidal islands on the south coast of Britain. It comes therefore as something of a statistical surprise to discover that the French end of this maritime connection is Mont St Michel, also a causewayed tidal island.

How to deal with this coincidence? The first of course is to dismiss it as a coincidence or more accurately as an artefact arising from overzealous historical revisionism. But a more realistic stance is to suppose that ancient mariners, for whatever reason, sought out tidal islands, built causeways on them and then arranged trade routes to exploit them. However, this is only acceptable by summoning up more coincidences:
1. why would nature provide so precisely for two tidal islands to be positioned at either end of the British tin-mining area
2. why would nature provide another tidal island at the precise place most convenient for land-sea transport of goods to the Continental interior
3. why would nature ensure that two of the islands so precisely lie on the shortest route to the mouth of the Rhone?
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Re: Trade Secrets

Postby Mick Harper » 5:33 pm

Extract Six

The purely statistical aspect of this conundrum would be solved by the simple positing of the notion that the traders were able to arrange for tidal islands to be situated where the trade routes needed them but since this challenges some of our most fundamental beliefs about the abilities (or more precisely the non-abilities) of Ancient Britons we might leave this on one side for the moment. If we return to the maritime section of our proposed tin route, it becomes evident that it crosses one other piece of land, the island of Guernsey.

Image

As will be recalled, there are just two causewayed tidal islands on the south coast of Britain so it comes as another statistical surprise to discover that there are two causewayed tidal islands on Guernsey. The first, the Vale, is represented here as the northern red portion. The channel between it and the rest of the island was filled in in 1806 but before that date the connection was made via a causeway at the western end between the two red sections.

Image

The bay here is called Grande Havre (Large Haven) and while the picture here shows that this might indeed be the case, there are only very small jetties there now so it would appear that at some time in the more distant past, this was a rather more considerable undertaking.

Image
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Re: Trade Secrets

Postby macausland » 9:59 pm

Time is money as we say today.

We build small jetties because it is more cost effective just like exporting jobs abroad or importing cheap labour here. Or getting slave labour perhaps.

In the past it is possible that the niceties of financial transactions weren't fully understood.

As with the standing stones perhaps there were many people willing (or not) available to do the work.

Build something large and permanent with the available labour and resources rather than build something small and cheap.

I believe Mao Tse Tung said something similar once when asked why the Chinese used so many people to build dams by hand when they could use machinery.

I imagine the megalithic people had a different philosophy but used what they had available. And what they knew would work.
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Re: Trade Secrets

Postby Mick Harper » 8:40 am

Extract Seven

The reason for positioning a ‘Grande Havre’ here is apparent if the actual line of the Great Circle is inspected. It goes through or is immediately adjacent to (it is difficult to reconstruct precisely at this scale) the other causewayed tidal island on Guernsey, Lihou Island

Image

The southern littoral of Guernsey is incredibly rocky and hostile to shipping in contrast to the generally benign conditions in the north. We may be sure then that careful provision is made for ships that, because they are following the Great Circle, have to round the south west corner of Guernsey.

The Great Circle itself, and presumably the ships also, leaves Guernsey at Corbière on the south coast whereupon the Circle and the ships have an unencumbered passage save the avoiding of the southwest corner of Jersey. This is called Corbière Point which of course may be just another coincidence.

Image
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Re: Trade Secrets

Postby Mick Harper » 4:53 pm

Extract Eight

This strictly geographical evidence will butter few historical parsnips. What is required is some historical link between the various causewayed tidal islands. We have circumstantial reasons to believe that Mont St Michel, Lihou Island, the Vale, Burgh Island and St Michael’s Mount are all concerned with the tin trade but what unites them in the historical record?

St Michael. All five islands have close connections with this enigmatic saint. Mont St Michel is of course the ‘Mount of St Michael’ as is St Michael’s Mount. Burgh Island used to be called St Michael’s Island. The Vale’s full name is St Michel du Valle and Lihou Island’s main feature was a priory that was subordinated to St Michel du Valle which was in turn an out-station of Mont St Michel. As indeed was St Michael’s Mount, and presumably, though there is no direct evidence, St Michael’s (Burgh) Island.

But of course this curious concatenation has a ready orthodox explanation, not requiring any elaborate pre-Christian trading connectivity. It can be plausibly argued that the sequence was

1. Some monks set up a monastery on Mont St Michel, choosing a tidal island presumably for reasons of security and/or seclusion

2. The monastery proved so popular that it was found advantageous to build a causeway to serve the establishment – it presumably did not adversely affect security and/or seclusion

3. So popular indeed that, in the way of all successful monastic orders, it was decided to bud off a daughter-colony using the same general method

4. In the nearby Channel Islands they found a tidal island, the Vale, built a priory on it and a causeway and called it St Michel du Valle

5. The Vale priory was so successful that it caused to have built a daughter establishment of its own on nearby Lihou Island, a tidal island, soon connected by its own causeway

6. Meanwhile the monks of St Michael were busy looking at the British mainland for suitable sites and found Burgh Island, built a monastery, and a causeway, called it St Michael’s

7. And finally did the same at St Michael’s Mount.

Of course this would require some fairly tortuous explanations as to why these monks, seeking solely divine inspiration, should happen to find their inspiration at places of such incredible geographic and economic significance. No doubt though something or other can be cobbled together. What is rather more difficult to explain is, not content with his dominance of the Great Circles on the sea-lanes, why St Michael should pitch up throughout the tin mining areas, dominating the most important Great Circle route on the British mainland.
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Re: Trade Secrets

Postby Boreades » 9:47 pm

Where do you get to if you project that line further south?
Does it go anywhere near the Corbières region in southern France?

http://fr.wikipedia.org/wiki/Massif_des_Corbi%C3%A8res
and
http://fr.wikipedia.org/wiki/Corbi%C3%A8res_(AOC)

The cultivation of vines in the Corbieres goes back to the 11th century BC , it was introduced by Greek merchants (see the Phoenician connection)
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Re: Trade Secrets

Postby hvered » 8:17 am

I'm glad you mentioned the Corbieres region as I'd been meaning to do more work on it. It's an important salt-producing area, the etangs or salt-lakes on the western half of the Golfe du Lion cover a large area of Languedoc-Rousillon

Image

The importance of the area to my mind is due to its location at the start of the east-west route that became known as the Camino to Santiago though it should perhaps be Las Medulas road.

Las Medulas are the largest, perhaps the oldest, gold mines in Europe

Image

The name Corbieres i.e. place of crows was the reason I was interested in the first place. The crow-name may have arisen from the straight-ish link between the land and sea routes of the Med and the Atlantic coast which Mick hasn't got to yet.
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Re: Trade Secrets

Postby Mick Harper » 10:23 am

Extract Nine

Loading ingots onto ships and dispatching them overseas is of course only half the story. There is at least as much difficulty (not to mention cost) in getting the material from the minehead to the port. If we assume the ‘Michael’ system utilises the twin causewayed islands at either end of the tin-zone, St Michael's Mount and Burgh (né Michael's) Island, then there is a need for transport provision from all over the peninsula to these two points since tin-mining itself takes place so widely. It is a fact of life then as it is now that the English West Country is not terrain that permits ease-of-travel either in terms of roads or an abundance of natural harbours.

Fortunately though the English West Country is long and thin and therefore amenable to the Great Circle method. We do not have historical records but we do have the geographical facts in an effort to reconstruct, at least in outline, how the problem was solved. Just as the Mont St Michel Great Circle exploits a helpful circumstance in the shape of France, so the St Michael’s Mount Great Circle exploits the shape of Britain. Here’s how:

1. The longest continuous land-line, ie not crossing water, it is possible to draw in a roughly west-to-east orientation across Britain, is surveyed.
2. If done by direct observation this will be a Great Circle
3. This turns out to be from Land’s End to the coast of Norfolk
4. And handily bisects the entire tin-producing zone.

Image
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Re: Trade Secrets

Postby Boreades » 11:51 pm

And handily bisects the entire tin-producing zone.


It might also handily bisect the lead, silver and coal producing areas in Somerset.
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