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There is a comment from the author in response to someone that I found fascinating, and I am quoting here to respond to:

> We found that even more of a threat than rain was one’s own sweat on a hot day. So, yes, it does need waterproofing, both inside and out. We did a number of experiments along those lines, and found that rubbing a block of beeswax over all sides of the armor provided nice waterproofing. It also makes the armor smell nice! When you wear it for a couple hours, your own body heat softens the glue a bit and makes it conform to your body shape, so it is much more comfortable to wear than rigid types of armor. Our reconstructions weighed about 10 pounds–about one third the weight of bronze armor that would provide the same degree of protection. Thanks for the questions!

It would explain to some degree why this armor may have found such military success during that time period, that it was more comfortably and more closely conformed to the body while offering similar protections. One of the things many people who've never had to wear armor for an extended period of time on a hot day don't realize is how horribly uncomfortable armor is, and how that discomfort can be a severe distraction under battlefield conditions.

One thing that also interested me about this is that we found that one of the strongest materials we have available to use in modern materials science is also laminated cloth, in this case carbon fiber laminates. By ensuring that the direction of the weaves are perpendicular to one another when doing a cloth layup, and using a sufficiently strong adhesive/sealant, these types of materials are incredibly strong. Carbon fiber and carbon kevlar both are exceptionally strong materials that would make great armor (and do), and it seems the linothorax is essentially an early application of some of the same ideas, with lesser source materials.



>One of the things many people who've never had to wear armor for an extended period of time on a hot day don't realize is how horribly uncomfortable armor is, and how that discomfort can be a severe distraction under battlefield conditions.

Maybe! A well tailored and properly weight-distributed mail hauberk (which is also conformal) is surprisingly comfortable for extended period of time in all kinds of weather. (Source: my own experience in medieval re-enactment). What gets you in hot weather are the textiles - with mail its the necessary padding under the mail that will cause issues in hot weather.

the author's point that linen was more comfortable than 'rigid' armor was probably true, but I will point out that rigid armors were also individually tailored, balanced, and created for optimal weight distribution.

As an aside mail armor was a successful and popular armor for a millennium, from the Iron Age to the middle ages (and continued to be successful as an augment to plate and in other contexts like South Asia and India until probably the 16th century). It was probably contemporary to the linen armor of the article (In time, not geographically - it was used most heavily in iron-rich regions in central Europe at first).


Linen is also going to be cheaper than bronze (and later iron), even though linen fabric is quite an expensive material by the standards of a pre-industrial society. If you can grow flax, you get edible flaxseed, flaxseed oil, and linen fibers for thread and then weaving... and next year, hopefully, you get a new crop of flax. Save the bronze for your swords.


Iron was likely relatively cheap to produce compared to Linen. You can find various YouTube videos of people processing iron ore by hand fairly rapidly though it takes significant quantities of wood or coal. Something like 2 weeks of labor to the extract and process raw ore for enough iron to make a breastplate seems likely. Though transportation would be an issue. Linen on the other hand required extreme processing simply to get thread and takes up valuable farmland, but could be produced locally. https://ulsterlinen.com/flax-to-linen/

Linen armor would only have been relatively cheap as a means of recycling old garments. However, that’s likely to degrade it’s protective value.


Raw ore wasn't the limiting factor for iron production: it was all about the wood. Coal has the issues that, without coking, it neither burns hot enough nor clean enough (i.e. it adds lots of sulfur to the iron, and the resulting alloy is inferior for pretty much all purposes). As a result, iron and steel production wasn't as bound by locality to mines nearly as much as it was by locality to fuel sources (i.e. forests).

To give a sense for the figures involved, 1kg of iron would require around 15kg of charcoal, which itself would have to be charcoaled from >100kg of wood.

From this, you end up seeing things like Elba being entirely deforested by the time of Caesar, and its still productive iron mines would have their ores shipped to the mainland for processing.


That’s not the complete picture. If 2-5 kg of iron ore + 15kg of charcoal makes 1kg of iron then moving the iron ore to charcoal is more efficient than moving charcoal to iron ore. The same was true of coal, though coal trade was extremely common for it’s use in heating and cooking.

Anyway, Bituminous coal was used in smelting of iron ore in Roman Britain, and China had long been using coal for steel production by that time period.

Also, wood was very much an abundant but managed commodity with various levels utility. Land was reserved for effectively farming it even after forests disappeared. The issue was these managed forests weren’t producing giant long straight trunks that you would find in old growth forests. Wood that’s fine for cooking or matching charcoal, can be useless for shipbuilding.


But that means you'd need to be constantly building new smelting facilities as local wood resources were used up. Making charcoal needs relatively little infrastructure, so it'd be easier to make and transport.

I suspect the optimal answer is a combination of approaches. Build a few foundries distributed optimally near large forests, cut timber and char it and bring the charcoal to the foundries. Maybe cycle them on a 40 year basis so you can re-seed the forests and grow enough timber to make them worth it.


This is one reason why Minnesota's large iron ore deposits were concentrated locally (if necessary, some of the Mesabi Range ore is already 65% iron) and shipped to Pittsburgh (near coal mines) for steel making, instead of shipping the coal to Duluth.

I grew up somewhat near railroad tracks in Minnesota, and it was surprisingly late that I realized most train tracks aren't littered with taconite pellets that fall off during transport.


Lebanon was covered in forests until the iron age


Iron? Or bronze?

I'd thought that the deforestation was already advanced by Greek times, though I can't find a clear reference to when or what factors were involved.


Mycenaean Greek or Athenian golden age Greek? The Mediterranean Bronze Age ended around 1177 BC


Hrm ... yeah the bronze-iron transition was earlier than I thought, though I'm still not sure when exactly Lebanon became substantially deforested.


Interesting!

That aligns with my understanding is that the real revolution of the iron age was not that iron was a superior material (at least initially), but that it was much more abundant than copper and (especially) tin for bronze, which democratized which people and societies were able to build iron gear.

A compelling theory to me of the late bronze age collapse is that in the bronze age, you had a very globalized society for the purpose of keeping the bronze supply chain intact. But ironworking eliminated the interdependence and the importance of the elite networks that sustained the supply chain. So then the whole "civilized" world quickly fragmented into much more micro polities. Many of the states that made the transition from Bronze Age to Iron Age relatively intact already had well developed ironworking.

The Assyrians were able to build a new value proposition for international empire. They institutionalized many of the civil and engineering innovations we attribute to the post-Roman world, kicking off what would become the classical era.


Completely anecdotally, but I recently read that linen was much more common historically than anglo-centric history suggests.


I’ve read a lot about the hoplite battlefield. I would rather be in a bronze corselet if facing another hoplite phalanx (which was the common city state standoff in the archaic and early classical period).

Also, the bronze xyphos largely disappeared with Bronze Age society. Some soldiers preferred them to iron swords in the archaic period because a bronze sword could be recast by its owner if it broke, where a blacksmith was required to reforge an iron one (though the iron sword was much less like to break and held its edge much better)


If I remember correctly, if you harvest for fibers, that's before it goes into seed.


Someone posted this link above (https://ulsterlinen.com/flax-to-linen/) which indicates that separating the seed is part of the processing.


This says there are many opinions in when is best to harvest the fibers, and that they believe it is before the seeds are ripe.

http://hoe-farming.com/growing-and-harvesting-linen-flax/


I thought it’s the seed stalk. The seed for oil, the stalk for fiber. The oil could have even been used as the polymeric resin for gluing the layers (and is very water resistant when it cures)


A lot of their work is speculative (e.g. it's not clear that the layers of linen were glued, but they went with the assumption). It's interesting that they did not consider one of the most likely combinations: linen layers sewn onto leather. This would be more flexible (glue makes linen quite stiff) and more sweat resistant.


It would also be relatively easy to puncture. Gluing the linen creates a composite material which should greatly outperform either of the component materials (the primitive animal glue will be almost crumbly on it's own, and woven cloth is very weak against punctures since there is very force holding parallel fibers of material close together). As is stated elsewhere, this is why things like fiberglass and carbon fiber are ubiquitous in the modern world.


Let me introduce you to the gambeson: https://en.wikipedia.org/wiki/Gambeson :)

Multiple layers of quilted cloth are extremely effective.


Im familiar, i think it works largely by being loose and giving. Arrows are fast, they have a lot of kinetic energy but relatively little momentum. You can decelerate them pretty effectively.


Thick layered cloth armor quite honestly also doesn't feel like something I'd bring if I was about go on a tour of conquest including such warm places as those conquered by Alexander the Great.


Having worn gambesons in the British summer during reenactment battles, I can't imagine wearing one in the Mediterranean sun let alone the Middle East. It gets extremely hot in there after even moderate physical exertion.


The glue is providing much of the structural strength. The fibers are providing tension to hold it together.

A similar approach has been used to make gears out of cloth. Stack cloth, cross-stitch, impregnate with resin, compress, cure, and then cut a gear out of the resulting block of material. It's one of those things people did before plastics. I have some old Teletypes with a few cloth gears, and you can see the woven pattern on the sides.


That is fascinating. I've not ever heard of that.

Can you share any more about that? Is there a particular name for it other than "cloth gears?"

I'm having a hard time Googling/DDGing it because "cloth gears" and every variation I can think of returns other things.

    It's one of those things people did before 
    plastics. I have some old Teletypes with a 
    few cloth gears, and you can see the woven 
    pattern on the sides


"Men and Volts", p. 317.[1]

Here's one you can buy, a replacement part for some old equipment.[2] Look at the large version of the picture. You can clearly see the stitching of the original cloth.

Composite materials, the early years. Composites are something long and thin with good tensile strength, combined with something strong but possibly brittle with good compressive strength. Probably the earliest composite was bricks with straw.

[1] https://archive.org/stream/menandvoltsstory00hammrich/menand...

[2] http://www.mcssl.com/store/4833177/fairbanks-morse-magneto-p...


Wow! That's fascinating. Thank you.


Search for "micarta gears". I'm not sure if that is a specific brand or a more general term but it results in lots of pictures. The gears are made of cloth and some sort of phenolic resin.

Seems the technique is also used by some for making knife handles out of cloth and epoxy resin.


Wood itself is a composite material (lignan are the fibres, other stuff is effectively resin). Adobe is a fibre-composit (mud and strawa), as is daub-and-wattle plastering.

We've come up with more interesting fibres and resins over the years, but the fundamental concept is ancient and impressively effective.


Does rebar and concrete count?


By any reasonable metric, I would say so.


Agreed.

There are newer variations including polymer-reinforced concrete (using fibres within the concrete matrix), and I'd be really surprised if there weren't developments using pre-stressed nets or webbing of polymers or other flexible fibres. That said, I don't follow the topic closely.


> By ensuring that the direction of the weaves are perpendicular to one another when doing a cloth layup, and using a sufficiently strong adhesive/sealant, these types of materials are incredibly strong.

I wonder if they tested that when creating their replica linen armor? That seems like the kind of thing ancient armor makers would definitely have tested out.




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