Estimage of time to construct ringfort

Meathlass · 18-12-2014 6:14pm #1

I remember from college that there's a formula to estimate how long it may have taken to construct certain sites. I think it was originally taken from observing men digging trenches during war time. It's often cited in tv programmes to make archaeology more accessible and I'm trying to do the same for a lecture this weekend.

So I have a ringfort which is 61m in diameter and ditch is c.2m deep. The formula is somethink like 2 men can move x amount of soil in x days.

I've tried googling but can't seem to hit on it.

AngryHippie · 18-12-2014 10:53pm

http://archive.org/stream/cu31924004135061/cu31924004135061_djvu.txt

See cost of shovelling.

Of course that will be making the assumption that modern tooling was available. I would reduce the production rates by at least 30% to allow for using bronze age tools.

slowburner · 19-12-2014 11:03am

Meathlass wrote: »

I remember from college that there's a formula to estimate how long it may have taken to construct certain sites. I think it was originally taken from observing men digging trenches during war time. It's often cited in tv programmes to make archaeology more accessible and I'm trying to do the same for a lecture this weekend.

So I have a ringfort which is 61m in diameter and ditch is c.2m deep. The formula is somethink like 2 men can move x amount of soil in x days.

I've tried googling but can't seem to hit on it.

The WW1 formula was that it took 450 men 6 hours to dig 250m of front-line trench.
By my calculation it would take 7 people (a more reasonable number for a prehistoric period?) 96 hours to dig a 61m ditch.

Both estimates sound pretty fast.

AngryHippie wrote: »

http://archive.org/stream/cu31924004135061/cu31924004135061_djvu.txt

See cost of shovelling.

Of course that will be making the assumption that modern tooling was available. I would reduce the production rates by at least 30% to allow for using bronze age tools.

Applying the increase in time required by 30% to the calculation above would give a figure of 125 hours for 7 people. Assuming an eight hour day of constant effort; that's around 16 days.
An eight hour day of constant digging is improbable. If we estimate a five hour day of productive digging, this produces an estimate of 22 working days for seven people to dig a 61m ditch. Which intuitively seems about right.
Of course this hinges on AngryHippie's estimated increase in time required due to the relative inefficiencies in prehistoric tools. It could be a higher percentage, it could be lower - who knows?

Meathlass · 19-12-2014 11:26am

Thanks for doing those maths Slowburner. I've recalculated it as 10 men would take 17 days just to have a round number.

As you say intuitively this seems right.

Hopefully now no-one questions me on my sums!

slowburner · 19-12-2014 11:39am

Meathlass wrote: »

Thanks for doing those maths Slowburner. I've recalculated it as 10 men would take 17 days just to have a round number.

As you say intuitively this seems right.

Hopefully now no-one questions me on my sums!

Or me!!

cfuserkildare · 19-12-2014 11:56am

AngryHippie wrote: »

http://archive.org/stream/cu31924004135061/cu31924004135061_djvu.txt

See cost of shovelling.

Of course that will be making the assumption that modern tooling was available. I would reduce the production rates by at least 30% to allow for using bronze age tools.

Perhaps even more time added to it due to not having things like Wheel-Barrows etc?

No?

Meathlass · 19-12-2014 11:58am

cfuserkildare wrote: »

Perhaps even more time added to it due to not having things like Wheel-Barrows etc?

No?

Wouldn't have needed them; they would have just heaped up the soil on the inside of the ditch to form a bank.

Meathlass · 19-12-2014 12:05pm

Just realised that the ringfort is 61m in diameter which makes its circumference 192m so it would have taken 10 men 41 days to dig the ditch.

cfuserkildare · 19-12-2014 12:49pm

10 men 41 days for the ditch, then how long to trample down the spoil-heap into a solid mound that would bear weight?

Meathlass · 19-12-2014 12:54pm

It would only need to take the weight of a palisade so wouldn't need too much time to shape it.

The interior of the ringfort is the same ground level as the exterior.

tac foley · 19-12-2014 11:07pm

No shovels, remember, just deer antlers. Probably carried spoil in backpacks supported by head-bands, á la Sherpa/porter in Nepal. As far as I know, there has never been any tool like a shovel found on or near any site of ring-fort construction. Of course, this may have been due to the fact that such a commodity may well have been melted down afterwards for re-use as another form of tool, or made shovels out of perishable wood.

Of course, we'll never know.

tac

slowburner · 20-12-2014 2:05am

tac foley wrote: »

No shovels, remember, just deer antlers. Probably carried spoil in backpacks supported by head-bands, á la Sherpa/porter in Nepal. As far as I know, there has never been any tool like a shovel found on or near any site of ring-fort construction. Of course, this may have been due to the fact that such a commodity may well have been melted down afterwards for re-use as another form of tool, or made shovels out of perishable wood.

Of course, we'll never know.

tac

As Meathlass said, there was no need to transport the spoil. It was just hefted up out of the ditch to form the bank.
We have shovels surviving from the Bronze Age but you are right, most perished. The few that survive are oak and were in exceptional conditions, such as the copper mines of Mount Gabriel.
Picks for breaking up soil were most probably cut from branching hardwood boughs. Not unlike the selection made by someone making a shillelagh.
I tried this myself once or twice with a suitable bough from a Holly tree and was astounded at how effortless and efficient it was in breaking up soil.

tac foley · 20-12-2014 12:04pm

Makes one wonder how long and how many it took to build Avebury or even bigger 'projects' like Maiden Castle.

But then we Irish have always been great with the pick and shovel...it's a genetic thing, I guess.

tac

RDM_83 again · 20-12-2014 6:16pm

I think its going to be massively influenced by the soil type and how many rocks are in it. I've dug a few ring-forts now including one monster one and it just seems to me that these estimates are a bit on the low side. You might race through the top meter if the soil is nice but once you get towards the bottom you will be slowing down a lot particularly since its not just the 2 meters depth its also the height of the bank your throwing the spoil onto.
I'm also not sure if 30% is enough an adjustment for the use of primitive tools, the right tools make a huge difference, even using a shovel with shorter handle is a nightmare and thats a comparatively trivial difference.
I also suppose it would depend a lot on the physical fitness level of the men digging, are they weedy calorie deprived serfs (can't think of the word- Beaghta?) or big well fed men, having dug beside a 17 stone man before I would say he worked at twice my speed

These are just my two cents though and not based on anything but feeling

tac foley · 20-12-2014 9:18pm

My guess is that all this happened before 'serfs' and slavish bondage were thought of as part of life's rich pattern - before Brehon laws, too. I would like to imagine that they were built by free men expressing maybe a religious belief as much as a way of affording themselves protection. It depends on how much credence you give to 'documentary evidence' like the 'Cooley Cattle raid' and similar semi-mythical accounts purporting to come from pre-Christian Ireland.

tac

slowburner · 21-12-2014 4:01am

RDM_83 again wrote: »

I think its going to be massively influenced by the soil type and how many rocks are in it. I've dug a few ring-forts now including one monster one and it just seems to me that these estimates are a bit on the low side. You might raise through the top meter if the soil is nice but once you get towards the bottom you will be slowing down a lot particularly since its not just the 2 meters depth its also the height of the bank your throwing the spoil onto.
I'm also not sure if 30% is enough an adjustment for the use of primitive tools, the right tools make a huge difference, even using a shovel with shorter handle is a nightmare and thats a comparatively trivial difference.
I also suppose it would depend a lot on the physical fitness level of the men digging, are they weedy calorie deprived serfs (can't think of the word- Beaghta?) or big well fed men, having dug beside a 17 stone man before I would say he worked at twice my speed

These are just my two cents though and not based on anything but feeling

It would be unlikely that there were particularly beefy or substantially well fed men at the time. And you could compare the more under-nourished to the prisoners of war who built the bridge over the river Kwai - they still managed a good job under severe conditions - as did many other emaciated prisoners in similar conditions. Which brings up the question: Are the weedy or calorie deprived always the less productive or efficient workers? So all in all the law of probability may balance these things out.

braddun · 21-12-2014 4:54am

depends on type soil,sandy,clay or some other,fitness of the diggers,tools available,time of year etc

but I guess 2 weeks with tea breaks

tac foley · 21-12-2014 2:12pm

slowburner wrote: »

It would be unlikely that there were particularly beefy or substantially well fed men at the time. And you could compare the more under-nourished to the prisoners of war who built the bridge over the river Kwai - they still managed a good job under severe conditions - as did many other emaciated prisoners in similar conditions. Which brings up the question: Are the weedy or calorie deprived always the less productive or efficient workers? So all in all the law of probability may balance these things out.

I don't understand what basis you have for thinking that the ring-fort builders were undernourished wimps on half rations.

By the standards of today, our ancestors were incredibly hardy, and far stronger - weight for weight -than we are today, simply because just living was hard all-round.

Do you really imagine that sructures like New Grange were built by weedy malnourished slaves?

Documentation on the actual physiology of the inhabitants of these islands would be very interesting to read.

tac

Poor Uncle Tom · 22-12-2014 10:31pm

Apologies, didn't mean to upset anyone,

tac foley · 23-12-2014 2:46pm

I guess I've got it all wrong. I thought that ringforts predated Christian Ireland and were, in fact, neolithic and later in origin.

Then you write that all this happened BEFORE the Celts, codified Brehon law.

When do YOU say the Celts arrived in Ireland? What you seem to be suggesting is that they arrived within recorded history, ie, the Middle Ages, in spite of an overwhelming body of evidence that they arrived around 800BC or so.

tac

Meathlass · 23-12-2014 3:00pm

tac foley wrote: »

I guess I've got it all wrong. I thought that ringforts predated Christian Ireland and were, in fact, neolithic and later in origin.

Then you write that all this happened BEFORE the Celts, codified Brehon law.

When do YOU say the Celts arrived in Ireland? What you seem to be suggesting is that they arrived within recorded history, ie, the Middle Ages, in spite of an overwhelming body of evidence that they arrived around 800BC or so.

tac

Ringforts are from early medieval Ireland (AD400-1000). All dating evidence so far supports this. Some may be a little earlier and may have been re-used prehistoric sites but I haven't seen any evidence putting them in BC times.

The idea that the Celts (as a distinct body of people) arrived is outdated; rather it was a cultural process. I'm not sure what point the previous poster (Tom) is making about the Celts. The Brehon Laws were written down in early medieval times but are from an older oral tradition.

tac foley · 23-12-2014 3:15pm

Thank you for clearing that up for me. So in historical terms they are a pretty recent invention.

Please educate me about the erroneous dating of the 'arrival of the Celts'. I've read enough of the Fidelma stories, written by an acknowledged expert Peter Tremayne, on Ireland of the Middle Ages, to know that Brehon Law was written in/around the 5th/6th centuries, but your take on the arrival of the Celts, in whatever form it took, would be appreciated, especially as the Big Island was Celtic from the time way before the Romans got there.

Quote - Genetic studies regarding Y-DNA Haplogroup I-M284 have concluded that there was some Late Iron Age migration of Celtic La Tène people to Britain and then onto north-east Ireland. In the late Iron Age Pryor estimates that the population of Britain and Ireland was between 1 and 1.5 million, upon which a smaller number of Celtic speaking immigrants could have installed themselves as a superstrate.

The arrival in Britain of cultural traits identified as Celtic is usually taken to correspond to Hallstatt influence and the appearance of chariot burials in what is now England from about the 6th century BC. However, several archaeologists, including John Waddell, say that there must have been "Celtic presence"[clarification needed] in Britain already in the late Bronze Age, i.e. in mid 2nd millennium BC

By about the 6th century AD (Sub-Roman Britain), most of the inhabitants of the British Isles were speaking Celtic languages of either the Goidelic or the Brythonic branch, leaving open the question of whether this had also been the case much earlier.

After Caesar's conquest of Gaul in the 50s BC, some Belgic people seem to have come to central southern Britain from the continent. Possibly because of this migration, the names of the tribes Parisi (in Eastern Yorkshire), Brigantes and Atrebates can be found both in Britain and on the continent. It has also been claimed that there were a tribe of Iverni in Ireland who spoke a Brythonic language.

In Ireland as in Great Britain, early Celtic influence is taken to correspond to the early Iron Age. The adoption of Celtic culture and language was likely a gradual transformation, brought on by cultural exchange with Celtic groups in Britain or southwest mainland Europe.

So if the early Irish were not Celts, what exactly were they? Cúchulain et al? Where from? What did they speak before Irish?

tac, even more confungled.

Meathlass · 23-12-2014 3:43pm

Traditionally archaeology studies were seen as one of invasion (the Beaker, Bronze, Iron people arrived, brought their new technologies with them and subjugated the existing peoples). It's now recognized that it was cultural and trade links which brought new ideas and technology around the world rather than military invasions.

Barry Raftery, who was a leading Iron Age and Celtic scholar, often remarked that if we didn't have the Irish language (Q- Celtic) that there would be very little evidence that Ireland had any contact with the Celtic world at all. We have none of the typical Celtic monuments, art or burials common in Hallstatt or La Tene and Insular Art of this time borrows a lot from passage tomb art and animal motifs common in northern Europe. In Ireland we don't have evidence for the amazing horse and chariot burials seen in Austria or the urbanized settlement pattern. Greek and Roman scholars also didn't call the Irish Keltoi.

The modern word 'Celt' comes from the Romantic revival in the 18th and 19th centuries and was used by Nationalists in Ireland in the 19th to differentiate us from England. This is when a lot of myths about the Celts became ingrained in our history and why people today often think that Newgrange, Stonehenge etc as Celtic monuments.

An arrival of a Celtic culture around 800BC is probably about right but it wasn't an invasion. There was no displacement of one people by another. Raftery has opined that perhaps high status wives from continental areas came to Ireland bringing their culture with them (or perhaps as slaves) teaching the language to their children (or their master's children) and gradually the culture becomes common.

Meathlass · 23-12-2014 4:01pm

tac foley wrote: »

So if the early Irish were not Celts, what exactly were they? Cúchulain et al? Where from? What did they speak before Irish?.

Our posts have overlapped a bit

The stories about Cuchulain and Na Fianna were written down in the 5th/6th centuries but they probably relate to events occurring in the Iron Age and late Bronze Age. These are political stories about validating existing rulers control and power and giving them a 'genealogy' stretching back into the mists of history. Neil Delamre's 'Holding out for a hero' (Fionn MacCool episode) actually looked into this subject and spoke to many of the academic talking heads. It's probably still on the RTE player.

The people probably spoke an Indo-European language but we have no record of it and we'll probably never be able to exactly figure it out. They were the Bronze Age people who had been here before. Did they think of themselves as Celts? Probably not.

The notion of nationalities and states is a very modern concept. What makes somebody 'Celtic' or 'Irish' or 'Roman'? When did people start considering themselves 'Irish'? Without written records for prehistory this is a fascinating but difficult area to study.

tac foley · 23-12-2014 4:05pm

Thank you.

I'll go throw all my incorrect textbooks away right now. Perhaps a better term would be invasive incursion, rather than a 'leap off the boats and attem, boys!' style of invasion.

tac

Meathlass · 23-12-2014 4:14pm

tac foley wrote: »

Thank you.

I'll go throw all my incorrect textbooks away right now. Perhaps a better term would be invasive incursion, rather than a 'leap off the boats and attem, boys!' style of invasion.

tac

That's the great thing about studying archaeology and history in general. The more evidence and research that's gathered the more the books have to be rewritten. Kelly's Ireland in Prehistory and Edwards Early Medieval Ireland are all wildely out of date in relation to their theories but they were excellent books in their time and the basics of them is unchanged but we have so much more excavation material now than they had to work from.

Don't throw your old textbooks away, they're worth a fortune, especially if they're out of print. One of my treasured books from my thesis is now worth 700% its value in 2001

Ipso · 23-12-2014 6:44pm

The term Celt is a fairly recent invention that is used to describe people who shared a similar language and broad culture.

Getting hung up in the point that celts never called themselves celts is pretty pointless as we have no idea of what people from yonks ago called theselves until they started writing things down or what other people wrote down.

La Tene and Halstatt are two features of 'Celticism' not the defining features.
Getting hung up on this (and they never called them Celts) is some kind of an attempt for Irish people to see themselves as unique and different from everyone else, imho.

RDM_83 again · 23-12-2014 7:58pm

One thing we can probably all agree on is that somebody badly needs to write a new book on Ringforts, Stouts work is well out of date now (written before the big road jobs of the 00's) and its fairly thin anyway.
I'm very surprised that an academic hasn't taken up the task yet as its so badly needed.

tac foley · 23-12-2014 10:58pm

Ipso wrote: »

The term Celt is a fairly recent invention that is used to describe people who shared a similar language and broad culture. /QUOTE]

Quote - The first literary reference to the Celtic people, as Κελτοί (Κeltoi), is by the Greek historian Hecataeus of Miletus in 517 BC.

This is recent?

What do think of as ancient?

tac

Ipso · 23-12-2014 11:27pm

tac foley wrote: »

Ipso wrote: »

The term Celt is a fairly recent invention that is used to describe people who shared a similar language and broad culture. /QUOTE]

Quote - The first literary reference to the Celtic people, as Κελτοί (Κeltoi), is by the Greek historian Hecataeus of Miletus in 517 BC.

This is recent?

What do think of as ancient?

tac

I mean more so the use of the term in the context of what we understand today based upon more recent linguistic, belief systems and archaelogical evidence.

I don't know what kind of detail the Greeks went into, I recall reading that they used it as a broad term for people beyond a certain area, likecwe might use Eastern European or Asian.

My main point was that I don't buy into Celto-Scepticism and based upon the modern classifications I mentioned that Ireland was indeed inhabited by Celts, the idea of a mass Iron Age migration from Switzerland/Central Europe needs an overhaul.
It seems that there was at least a male dominated elite movement at some point from the mid bronze age onwards (perhaps with the bell beaker phenomenon), and then some Iron Age movements from Britain like the Cruithin and Brigantes (most likely due to Roman expansion there).

slowburner · 24-12-2014 2:08am

One of the problems in this discussion is a precise understanding of the term ringfort.
This probably arises out of an necessary vagueness in the listing and dating of circular and sub-circular enclosures on the RMP.
The fact of the matter is that not all circular enclosures are ringforts. Some are Iron Age, some are Bronze Age and an emerging number are firmly Neolithic.
Part of the uniqueness of Irish enclosures is that while the Romans were busy with set squares, lines and levels, and rigorous layouts, we Irish laid things out in a much more laid back manner.

I would personally like to thank Poor Uncle Tom for his contribution to this thread.

Estimage of time to construct ringfort

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