Post by: Petrochemicals on 26/07/2023 21:16:23
Post by: alancalverd on 26/07/2023 22:07:51
I think a clue is in a bronze-age tomb in Wiltshire, where archaeologists found Scandinavian leather, Irish gold, and Indian silk and spices. As I see it, there was an established trade route along the European coast and through North Africa long before the Romans got their act together. The Phoenicians certainly traded with Cornish tin miners (vital for making bronze) and Celtic-style glass turns up in all sorts of places. The close relationship between west Britain and Brittany survived until WWII, with clear linguistic connections between the Welsh, Breton and Basque languages (and, oddly, Hungarian).
The direct sea route from Britain to Spain is still dangerous, but if the natives are friendly (and they still are) it's relatively easy to cross the English Channel and take the land route through west France. So when the Romans invaded Brittany, it really disgruntled the coastal traders. In de Bello Gallico Caesar grudgingly admits that the Gauls did not submit willingly and indeed seemed particularly keen and able to fight. Hence the long, shallow French coast was not as defensible as they would like, and the "savages" across the water were actually well equipped guerrillas prepared to fight to keep their businesses and families connected.
Thus it made sense to invade England and establish a defensible land border at the narrowest point of the big island. What always amazes me is the accuracy of their maps and intelligence - Hadrian's Wall is perfectly positioned along a geological fault across the thinnest neck of the island, and an astonishing feat of planning, execution and development over subsequent hundreds of years. South of the border, Roman domination was more political than military, achieved by a series of bribes, deals and occasional skirmishes with individual tribes: a true divide and conquer policy that diluted rather than opposed any aggression from the west.
Post by: Petrochemicals on 26/07/2023 23:16:28
South of the border, Roman domination was more political than military, achieved by a series of bribes, deals and occasional skirmishes with individual tribes: a true divide and conquer policy that diluted rather than opposed any aggression from the westI get the impression the Romans will have increace the living standards and opportunities many many times thus giving a take over by mutual consent, there where battles but I guess there where people who where glad to see the Romans come. I doubt even the roman empire could have mounted a campaign across the channel against a resolute large populace, they couldn't sustain occupation across the Rhine, thus likewise for the celts across the water could not have caused a revolt in Gaul.
I'm sure there where trading links many years ago, recently I read about Europe's earliest complex culture.
https://en.m.wikipedia.org/wiki/Varna_culture
Post by: Bored chemist on 26/07/2023 23:33:26
It's always worth asking why the Romans bothered to invade these cold, wet islands at all."Because it's there".
Even poor people are worth taxing.
Also, silver, lead salt, iron etc.
Post by: paul cotter on 27/07/2023 08:59:57
Post by: paul cotter on 27/07/2023 14:16:01
Post by: alancalverd on 27/07/2023 15:14:22
They took one look at Ireland, decided it was a land of perpetual rain( right now it most certainly is ), not worth the bother, and called it Hibernia, ie land of winter.
Possibly, but the Irish Sea is a bigger challenge than the English Channel (you can't see across it from anywhere south of Scotland, and the magnetic compass hadn't reached Europe) and the west coast of England and Wales was either defensible (cliffs and rocks) or populated by folk whose loyalty could be bought, so it seemed a reasonable boundary to an empire with plenty of infantry but little in the way of a navy.
Post by: Bored chemist on 27/07/2023 16:28:40
you can't see across it from anywhere south of ScotlandReally?
https://www.dailypost.co.uk/news/north-wales-news/amazing-north-wales-views-ireland-11654334
https://www.historic-cornwall.org.uk/can-you-see-ireland-from-cornwall/
https://www.anglezarke.net/can-you-see-the-republic-of-ireland-from-england/
Even if they didn't see it, they knew it was there.
Incidentally...
Did Britain bring down the roman empire?
No.
Post by: alancalverd on 27/07/2023 17:33:15
So technically, yes, I have seen the Irish coast "from" Cornwall, but I was about 10,000 ft above Bodmin at the time.
Standing on a Pembrokeshire beach, your horizon is about 3 miles away. If it isn't raining or snowing you might indeed catch a glimpse of Mullaghcleevaun from the top of Yr Wyddfa, but could you tell anyone?
I think the Romans just gave up the battle against Celtic languages and went home. On one side of the sea, it was all consonants, and on the other, they didn't pronounce most of the letters, yet these people were cousins! Years later, England was allegedly defended by an advertisement on the Dover cliffs: "Ovaltine - pronounced success!"
Post by: paul cotter on 27/07/2023 18:26:56
Post by: Bored chemist on 27/07/2023 19:05:37
, I have seen the Irish coast "from" Cornwall, but I was about 10,000 ft above Bodmin at the time.It doesn't matter how high you were, does it?
Ireland can be seen from England.
Post by: alancalverd on 27/07/2023 22:23:26
It doesn't matter how high you were, does it?I never considered you to be a flat-earther.
http://www.totally-cuckoo.com/distance_visible_to_the_horizon.htm
Post by: Petrochemicals on 28/07/2023 05:29:54
It's 26 miles from Dover to Calais, Dover cliffs are maximum 350 ft height.It doesn't matter how high you were, does it?I never considered you to be a flat-earther.
http://www.totally-cuckoo.com/distance_visible_to_the_horizon.htm
calais-cliffs-e1538558616100.jpg (135.79 kB . 800x387 - viewed 260 times)I think they are incorrect. They may be higher that the beach though and I hay be wrong.
Post by: alancalverd on 28/07/2023 11:27:02
Hartland - Waterford is about 140 miles, Whitehaven - Downpatrick 88 miles, neither visible from ground level.
In a small plane we usually route Strumble- Rosslare or Holyhead - Dublin , about 60 miles and just visible from 2000 ft, but the departure points aren't in England.
Post by: Bored chemist on 28/07/2023 13:29:17
Even if you are at the bottom of a mine, Ireland can still be seen from England- just not by you.It doesn't matter how high you were, does it?I never considered you to be a flat-earther.
http://www.totally-cuckoo.com/distance_visible_to_the_horizon.htm
The fact that you saw it from 1000 feet is irrelevant, isn't it?
Post by: Bored chemist on 28/07/2023 13:30:22
That pretty much concurs with the horizon table, particularly at low tide.Does the table take refraction into account?
Post by: alancalverd on 28/07/2023 15:09:00
Even if you are at the bottom of a mine, Ireland can still be seen from England- just not by you.Nor by any Roman colonist.
So technically, yes, but....
Post by: Bored chemist on 28/07/2023 18:28:20
Nor by any Roman colonist.Maybe the odd ghost of a Roman.
Post by: Petrochemicals on 28/07/2023 22:31:42
That pretty much concurs with the horizon table, particularly at low tide.It's probably down hill.
Hartland - Waterford is about 140 miles, Whitehaven - Downpatrick 88 miles, neither visible from ground level.
In a small plane we usually route Strumble- Rosslare or Holyhead - Dublin , about 60 miles and just visible from 2000 ft, but the departure points aren't in England.
Post by: alancalverd on 29/07/2023 12:16:28
Post by: Petrochemicals on 31/07/2023 08:38:03
Of course! Light travels faster downhill, so the Irish can see me coming before I see them on the ground. All that wartime stuff about Chain Home Radar was public disinformation: it really was the Royal Observer Corps on a diet of carrots!I suppose that's how we get tides too.
Screenshot_20230729_041700.jpg (190.97 kB . 1804x1065 - viewed 243 times)I think that this is correct, swingate is a transmitter station with 100m ish tall masts. It does produce a quandary.
This is a shot of Aberystwyth from about 7.5 miles away,
IMG_20230731_083639.jpg (1230 kB . 2301x1447 - viewed 245 times)It does show the line of sight, the waves are obviously raising the sea level, there is a bit of miraging, but you can see the height of the buildings. The building on the end is the castle and then Aberystwyth University.
0_Old-College-Yr-Hen-Goleg-Aberystwyth.jpg (47.4 kB . 615x409 - viewed 249 times)Post by: Bored chemist on 31/07/2023 11:52:19
That pretty much concurs with the horizon table, particularly at low tide.Does the table take refraction into account?
Post by: alancalverd on 31/07/2023 14:04:42
This is a shot of Aberystwyth from about 7.5 miles away,Entirely reasonable. Assuming the camera was about 6ft above sea level, you can't see the beach or even the hulls of the inshore yachts. The minimum sum of observer height plus target height at 7.5 miles is about 35 ft.
Does the table take refraction into account?no. But it's not a lot of help over a long stretch of water: any significant temperature layering is usually accompanied by fog!
Post by: Bored chemist on 31/07/2023 14:56:31
Post by: alancalverd on 31/07/2023 16:59:21
Post by: Bored chemist on 31/07/2023 17:33:24
But when we talk about visibility to the horizon from the shore, both the target and the observer are at the same altitude and therefore pretty close to the same pressure and, if we are looking across the sea, the same temperature. At most, you might add 10 - 15% to the visible distance.Do you remember the Daedalus cartoon/ column in Nature and or New Scientist?
Written by David Jones.
He covered the subject. I will see if I can find the book.
But the point is that the change of refraction with altitude is such that light "curves down" and the curvature is nearly the same as the curvature of the earth.
This sometimes upsets flat earthers .
Post by: Bored chemist on 31/07/2023 17:44:00
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Post by: Bored chemist on 31/07/2023 17:46:48
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Obviously, the copyright isn't mine.
I'd recommend the book
https://www.amazon.co.uk/Inventions-Daedalus-Compendium-Plausible-Schemes/dp/0716714132
Post by: alancalverd on 31/07/2023 23:17:54
the curvature is nearly the same as the curvature of the earth.So you can establish line of sight communication between any two points with a decent laser. Just as well the Romans didn't know that. Surveyors use an "effective radius" of about 1.17 times the actual radius of the planet to correct their optical height measurements, but clearly they know nothing about surveying.
Post by: Bored chemist on 31/07/2023 23:38:41
So you can establish line of sight communication between any two points with a decent laser.What?
Who said that?
Post by: alancalverd on 01/08/2023 10:26:37
the curvature is nearly the same as the curvature of the earth.then a collimated beam will always follow a great circle around the planet, at its initial altitude.
Post by: Bored chemist on 01/08/2023 11:47:48
If the path of a light beam is curved such thatTell us you don't know what "nearly" means without saying "I don't know what 'nearly' means".the curvature is nearly the same as the curvature of the earth.then a collimated beam will always follow a great circle around the planet, at its initial altitude.
If, on the other hand, you made a tunnel 13 km below the earth's surface and let it fill up with air then, yes, you could send a beam of light round the world.
Whether 13 Km is deep or not depends on perspective.
It about as deep as we have ever drilled.
But compared to the 6300Km radius of the earth, it's pretty near the surface.
Was the problem that you didn't read my post, or that you didn't read the article in the book?
Post by: alancalverd on 01/08/2023 11:59:05
Post by: alancalverd on 01/08/2023 12:04:57
OK, how near is nearly? If I fire my laser horizontally from 100 ft above a featureless (no mountains to get in the way) earth-size planet, at what height will it return along some elliptical path? Or if I tilt it down a bit from the top of the only (arbitrary height) mountain, will it get back to me?This does raise some interesting possibilities with respect to small planets with dense atmospheres - like Venus - or all-gas giants .
Post by: Bored chemist on 01/08/2023 18:09:29
OK, how near is nearly? If I fire my laser horizontally from 100 ft above a featureless (no mountains to get in the way) earth-size planet, at what height will it return along some elliptical path? Or if I tilt it down a bit from the top of the only (arbitrary height) mountain, will it get back to me?I don't see any reason to assume that it will be elliptical.
Feel free to do the maths.
Post by: Petrochemicals on 01/08/2023 22:22:42
It appears on the one hand you can see roughly down to the road which appears about the 10m mark, but the tides can be 7m, the uni building is in orange. The pink boxes display some sort of downward markings as though the image is stretched.This is a shot of Aberystwyth from about 7.5 miles away,Entirely reasonable. Assuming the camera was about 6ft above sea level, you can't see the beach or even the hulls of the inshore yachts. The minimum sum of observer height plus target height at 7.5 miles is about 35 ft.Does the table take refraction into account?no. But it's not a lot of help over a long stretch of water: any significant temperature layering is usually accompanied by fog!
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The sea has waves, but it could be altered in its level by the tidal flow, tides are not equal.
Post by: alancalverd on 01/08/2023 23:59:52
I don't see any reason to assume that it will be elliptical.Because it's "nearly" circular!
Post by: Bored chemist on 02/08/2023 08:42:43
If the "force" vs distance function was an inverse square you would get elliptical orbits.I don't see any reason to assume that it will be elliptical.Because it's "nearly" circular!
But the bending vs height is not quadratic.
And any other function won't give stable orbits.
Post by: Pseudoscience-is-malarkey on 13/08/2023 20:08:57
There was defiance in the British Illes that at times made things difficult for the Roman occupiers - defiances led by warriors and political figures of sorts who were possibly the influencers of the Matter of Britain. But in the grand scheme of things, the fat statesmen of Imperium Romanum considered them as worrisome as a cloud day.
Post by: alancalverd on 17/08/2023 09:12:21
the fat statesmen of Imperium Romanum considered them as worrisome as a cloud day.And there you have the key to the collapse of all empires. The political core (being composed of parasites) rots, and like any other cancer, it draws resources from the periphery to feed and defend itself, or issues central commands that do not reflect local intelligence. The distant warriors, farmers and traders who establish, maintain and benefit from an organised society are withdrawn or ignored. Some become rebels, others succumb to depredation from outside, and gradually the Huns, Visigoths, Americans and Scottish Nationalists replace order with chaos, then build a new order remarkably like the old one, until their own internal parasites repeat the process.
Post by: Petrochemicals on 17/08/2023 17:43:18
No, the Roman Empire was mostly brought down by the "uncivilized" Visigoths who had colonized much of Western Europe,That was rather the point in the op, Britian being a island, also with atrocious weather, even worse back then, with little development(Britian has been habituated and emptied many times due to ice ages). It must have taken much in resources to conquer Britian for little gain in manpower or riches, stopping a conquest of the East of the Rhine being captured and leaving Rome vulnerable. Would you reccomend invading a militant Canada if Mexico where a threat?
https://historypoints.org/index.php?page=britains-oldest-burial-site-gower
Post by: alancalverd on 18/08/2023 09:18:29
Britian being a island, also with atrocious weather, even worse back then,Depends on your definition of atrocious. The east coast of Scotland was known in Roman times for its grape harvest and subsequent Vikings found the climate very conducive to invasion and agriculture. Roman soldiers seemed quite content with their short skirts and bare arms for the entire occupation and AFAIK there is little evidence of uniform greatcoats or fur skins, though they were common enough further north. Chimneys and the use of indoor fires for space heating rather than just cooking, did not appear until the 11th century AD.