Here's a little archaeological riddle I've been thinking about. From about 1350 to 1700, three-legged brass cooking pots were common in Sweden. When metal detecting in ploughsoil, you often find bits of them. They're easily found as the fragments tend to be large and heavy: they make the detector sing loud & clear. But here's the thing: you almost only find the feet and legs of the pots, hardly ever the wall or rim. Why is that? I think I've come up with an answer.
These pots weren't used out in the fields. The reason that we find the feet there must be that household refuse was thrown on the manure pile and then carted out into the infields as fertiliser. The most likely place for a brass tripod pot to lose a leg was on the hearth in the kitchen. But this was not likely to go unnoticed: the pot would get overturned and spill its contents when it lost one of its three legs.
So, you have a broken brass pot that's missing a leg, and you know where the leg is: among the embers on the hearth. What do you do? You put the broken pot away to sell it as scrap. But you can't get the leg immediately: it's glowing hot and possibly buried among the embers. So you decide to get it the next time you clean the ashes out of the hearth. And here's where I think the legs get lost.
These hearths aren't cleaned daily. When they do get cleaned, the person doing that chore needn't be the same person who was using the pot when it broke, and if it is the same person, then it's not certain that they still remember the broken leg. Also, in order to clean out the hearth without burning down the house, you need to put the fire out completely, which means that you're working in the dark.
So every once in a while, legs and feet of these pots get thrown with the ashes onto the manure pile, and then carted out into the fields, where they spend 500 years before a metal detectorist finds them.
Update 15 March: Dear Reader Lassi Hippeläinen pointed something out that I hadn't thought of. "IMHO that pot was hanging from chains when it was over fire. It was standing on its legs only when it was brought to table." And I agree. I'm not sure what this means for the likelyhood of legs breaking off on the hearth.
[More blog entries about archaeology, Sweden, Medieval, Renaissance, middleages, metaldetecting; arkeologi, medeltiden, renässansen, metallsökare.]
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Interesting speculations, Martin. Those brass pots remind me of similar pots from Shang Dynasty China. Convergent cultural evolution, perhaps!
Pretty nifty theory, and most likely its one of the reasons we find them. However, we do find handles as well as shards of the vessels themselves, but I think that it is more likely that a pot leg will be recognized for what it is than a shard of the bowl.
You think the average detectorist would keep a vessel leg, but not a vessel wall or rim fragment? Look at the relief decoration on those walls. I'd be surprised to find someone throwing that away. I'm basing my impression on investigations where the deal has been "show almost everything except bottle caps to Martin".
Would there be a way to test this theory? If, say, the broken edge would be molecularly different if it spent time in a fire than if it were just in the air (and buried) for 5 centuries?
OK, but .... why not just weld the foot back on? Is there evidence from these feet that you do find that they've been re-welded once or twice or have started to get "bronze disease" at their proximal end (either of which would make it harder to re-weld them).
Good idea!
Now all we need is a funding body that's really interested in the doings of 15th century scullery maids! (-;
I'm not sure if it's possible to weld brass. The zink goes up in smoke and you end up with impure copper. And in order to be able to reattach the leg, you would need to remember to collect it from the ashes. The legs we find are, I believe, ones that were forgotten.
A really interesting idea. My own finds from a little English village number 13 copper-alloy vessel pieces (mostly rims) and just three feet. But UKDFD seems to show mostly legs.
Do you find those little diamond-shaped rivets that were used to mend pots? I do, so I would be surprised if broken legs were not re-attached, assuming this is possible.
I think we would be brazing or soldering, not welding. I don't know if those techniques would withstand the temperature the pot would see during use. Brazing, at least, would probably work as long as the pot contained liquid.
I don't buy that explanation. In the old times people tried to fix or reuse things to the last.
I'm not familiar with the technology, but as an engineer (and a grandson of a village blacksmith) I'm entitled to Make Guesses. The feet are probably attached by soldering, not welding. And certainly not by riveting, which would require holes in the pot.
If the contents of the pot boil off, it may get so hot that the solder melts, and the feet get loose. They can be salvaged from the fire immediately with a poker. Fixing them back is easy enough even without the skills of a blacksmith - if you have the solder to do it.
However, a footless pot can still be used for other purposes. So maybe the feet were discarded, if there was no solder to fix them, but the vessel itself was kept for other uses. And then at some later time a travelling smith attached new feet, which would explain why there are more feet than pots.
Charles: No, I don't recall any rhomboid rivet heads. But then I'm just a baby detectorist who's happy to get to play with the big kids.
Wikipedia informs me that "Brazing is a joining process whereby a filler metal or alloy is heated to melting temperature above 450 °C [..] and distributed between two or more close-fitting parts by capillary action. At its liquid temperature, the molten filler metal and flux interacts with a thin layer of the base metal, cooling to form a strong, sealed joint."
Lassi: The pots were cast in one piece, legs & all.
I'm with Lassi in being sceptical of the fireplace hypothesis, at least in its original form; as she suggests, you could fairly fish the hot leg out of the embers with a poker or somesuch if there was any intention of keeping it.
My suggestion would be that broken legs would be immediately tossed out while the pot itself would be reused in a different context, at least for a while.
A 1x1 cm shard of that vessel would not look very spectacular and to determine whether a small copper alloy shard comes from a vessel or not is not the easiest thing in the world to determine at first, or even second, glance.
Not all fragments are so large that they exhibit obvious curvature and most are very plain without decoration. However, this does not mean they get tossed. Just about all copper alloy items, shards and feet and whatnots, are delivered to the museum. So even if they are not positively identified by the detectorist, there is little risk of the museum losing out on them.
For your viewing pleasure here are some nice examples of largely intact finds from Denmark:
http://www.detekt.dk/sdf/funddatabase/albums/userpics/10049/malmgryde_0…
http://www.detekt.dk/sdf/funddatabase/albums/userpics/10001/rune_gryde…
The walls and rim are thin. They wear out and corrode more quickly than the thicker feet and legs.
Tobias: I can only speak for myself, but at my sites I believe we'd be able to identify wall fragments unless they were one square cm as you suggest.
Good point, Jeff. But still these ploughsoils allow us to find small copper coins that would be even more vulnerable to erosion.
Some rambling thoughts.
Welding is joining two pieces of metal by melting, using only the same types of metals. ie a filler metal (if used at all) is the same alloy as the joined pieces.
Brazing is joining two pieces of metal using a different filler metal.
I think it's called brazing as the commonest type of brazing that you will find is a steel to steel joint using a brass alloy as the filler. However, I have brazed aluminium with a lower melting point (than the parent metal) aluminium alloy. It is also possible to weld aluminium too. Different filler rods and fluxes are available for both methods.
I agree the broken leg would be easily salvaged from any fire, so that's a non starter of an idea. All the pieces of the broken pot would be available to the owner so a repair should be possible. Either welding or brazing of the pot leg for a repair is plausible. However would it be practical? I am not so sure. If a person wasn't skilled in metalwork and/or had no specialist tools it would be very difficult.
As an unskilled metalworker owning a pot with a broken leg which can't be sat down level, what would I do?
Chop off the other two.
In the surviving pots do the legs look complete?
Martin's heading photo shows a nice pot with long slender legs that has obviously been kept in good condition, but the first pot in Tobias' links shows short stumpy legs and I may be imagining it, but not quite the same length as each other.
Now you have a useable pot (with shorter legs) and three broken legs. As the person is not a metal worker what can you do with three spare legs? Maybe you can use them as weights or something, but possibly you sling them out.
Howzat.
I've gotten the idea that scrap metal was collected quite painstakingly in the period in question, but I may be wrong.
PS I wasn't clear enough.
Welding melts the parent metal.
Brazing doesn't.
Of course the wife could of thrown the leg away in disgust since it's just spilt the evening dinner, the kids play with it in the fields using their vivid imagination. The kids get bored with it and drop it or put it in a 'safe place' and isn't found again for another 500 years.
I'm basing this on my experience of my 7 year old daughter who has the amazing ability to store or randomly drop things throughout our house.
: )
here in North america, you get lots of kettles traded in by the french during the early contact era. Marti Latta and her students were the ones that realized that most of these pots were being cut apart and reused as knives and such. Perhaps that's what happens to the rest of the pot? We get left with the riveted sections where the handles were attached because they're too thick to use, maybe you get left with the legs? Of course, we also have all these pieces we called 'scrap' which turned out to be expedient tools.
I rather believe the legs were torn off and discarded when people started to use iron stoves. Many of these pots were probably still in use at this time. Why throw away a good pot? If this is true most of the loose legs are likely to be from the 18th Century rather than earlier.
brazing and welding, these days, is done with gas torches. blacksmithing in the renaissance would have been done with charcoal furnaces, a whole different story. a skilled brass-smith could probably have welded a leg back on, but your average farmer or housewife might well have had trouble doing that. how easy might it have been for your random average person in those days to get to, and hire the services of, skilled metal workers?
the stereotype is of each village having its own blacksmith back then, but was that actually true? and even if it was, would such a village blacksmith have worked a lot with brass cookware, or been more specialized towards farm tools and horseshoes?
Brass casting was a specialised urban craft. The village blacksmith wouldn't have been able to do much about a busted pot.
In the previous comment when I wrote "possibly...sling them out" I didn't mean that as the most likely action. I am sure the intrinsic value of the metal would mean that the owners would likely hang on to them. But would a person make any special arrangements to trade them (how valuable would they be?). Once stashed away to do something with "later" what would actually happen to them.
On the other hand if the owner wanted to use them for something, realistically what could you do with one or more lumps of bronze. I can well imagine uses such as knives or scrapers from other parts of the pot as megan suggested. Anyone got any thoughts?
Alex's comment about his daughter rings true too. :-) I had a cousin who was notorious for losing her dummies (pacifiers?) as a small child. They were still being found in nooks and crannies when the family moved out of the house 25+ years later.
Somebody - a very enthusiastic blogger - named Greg Laden suggests "rewelding" the legs to the bowl.
He doesn't know (1)anything about bronze, and/or (2)welding, and/or (3)either one.
You can't/don't "weld" bronze. Solder it, or braze it - but not weld. And the temperatures as which solders melt is likely to be less - substantially less - than really hot fireplace fires - there wouldn't be much point in it.
But - who said you had to know anything to blog?
"Lassi: The pots were cast in one piece, legs & all."
Live and learn... The pot in the figure looks more like hammered from sheet metal. The thin walls and inward sloping detail are very difficult to make with casting.
BTW, there are two other details worth noting. The legs are pretty short. There's not much room under the pot for fire. Also the handles are vertical. That works with coffee cups that are held with one hand, but kettles need horizontal handles. IMHO that pot was hanging from chains when it was over fire. It was standing on its legs only when it was brought to table.
@Nomen Nescio: there were travelling smiths, and people could travel to smiths. And people were pretty skilled on their own. They had to be. Smiths were in a class of their own. My grandpa worked metal, wood, and leather with ease. From tractors to kid's toys.
@James Johnston: the pot won't get hot in a fire as long as there is water inside. You can boil water in a paper cup.
These people were highly unlikely to re-use bits of brass pot for knives and scrapers. They had been producing iron for 2000 years at this point.
Lassi: I agree with your theory that the pot would have been hanging over the fire, rather than standing in it - but with only two handles, wouldn't the pot hang very unsteadily? Unless there's a third handle we cannot see in this picture?
Perhaps it was put in some sort of contraption/support while over the fire, and the handles used for moving it afterwards?
I haven't got very much experience cooking things over an open fire, unfortunately. :)
No - the handles are above the centre of gravity, so the weight will force it to hang fairly stable, exactly like hanging a billy can over the fire on a bail wire.
... or lifting a bucket by its handle.
My granny used to do her laundry in a big pot a lot like that, which also had three feet, one of which broke off. She didn't fix the broken foot, but propped up the pot on a brick and kept on using it until it eventually developed a nasty hole. She used to boil water in that big pot, believing that was the only way to get the laundry well and truly clean, until her oldest son convinced her to get a wringer washing machine. She kept that device for 30 years until the same son got her a more modern one. I like your explanation.
Has anyone checked the tops of the legs to see if they all broke off? Were any of them removed on purpose? I assume they would show intentional rasping to create weakness and get them to snap off. If a pot loses one leg, it is unstable. If it is a fairly large pot that does not have a lot of curve on the bottom, as the pot in the picture, and one needs to continue to use it, it might be advisable to snap off the other two legs. The pot then continues to be used until there is another reason-- a hole in the body of the pot-- to recycle the metal.
Some random comments:
As Martin said, these pots were cast in one piece (cire perdue) and yes, the walls are very thin (as little as 1-2 mm).
A pot made from sheet metal is called a kettle.
An interesting question is wether the legs break - or wether the body around the leg breaks, leaving a hole in the pot. If the body is left intact when the leg breaks off, the pot will remain perfectly usable: You could prop it up with a stone or a brick - no problem - or just leave it hanging from the (usually wrought iron) handle that would have been attached to the ears.
Whatever process went before the leg was discarded, Martins explanation sounds reasonable to me:
"So every once in a while, legs and feet of these pots get thrown with the ashes onto the manure pile, and then carted out into the fields, where they spend 500 years before a metal detectorist finds them"
At my sites, only one of the legs have had a bit of the wall attached to it.
FYI the handle attached to the ears would look something like this: http://mis.historiska.se/mis/sok/fid.asp?fid=107206
I'm not sure if it's possible to weld brass. The zink goes up in smoke and you end up with impure copper.
Right. You can indeed weld brass, maybe once, and it won't be a good weld, but the second weld will suck even worse. Maybe it can be soldered, though.
As improbable as it may seem, I collect old hammered, or chased, copper pots and implements. My oldest examples are of African origins and have dome shaped bottoms, and no feet. Some of my Swedish items have feet, but the feet are all riveted to the body and are iron. I can make rough guesses as to age of the items by the number of times it has been patched. Copper was the Tupperware (does that translate into Swedish?) of the preindustrial kitchen. It could be readily repaired by the owner or traveling tinkers who often carried extra parts, legs among them. With new pots coming into use, brass being less valuable and harder to recycle and old pots being scraped there would naturally become a surplus of stray legs. If people didn't constantly lose stuff archaeology would be a much duller science.
Yes, I know the kind of riveted and soldered sheet copper vessels you refer to. They tend to have iron feet and handles, right? The feet we find in the fields are a bit older and belong to cast brass vessels.
The vessels with riveted feet are newer than your pot. I went beck over my collection, and without exception the copper pots that come in direct contact with fire are riveted. Your all brass pot was probably cast as one piece, but I can't say because I can't remember ever seeing such an example.
Has anyone checked the tops of the legs to see if they all broke off? Were any of them removed on purpose? I assume they would show intentional rasping to create weakness and get them to snap off. ... If a pot loses one leg, it is unstable. ... it might be advisable to snap off the other two legs.
Interesting idea! The ones I've seen haven't shown any apparent traces of sawing or grooving, but they do tend to be pretty abraded from centuries in the ploughsoil.
Hello! I am highly interested in your discussions about the cauldrons! In our museum in the Netherlands we have a nice collection and I am thinking about organizing an exhibition in the future on these brass/bronze/cast iron pots. Besides that, we are preparing a future website about art (paintings and engravings) and artefacts, called ALMA, see the announcement: http://www.boijmans.nl/en/169/afbeelding-linkt-met-artefact
And ofcourse this research also shows examples of these tripod cauldrons. We will launch this website next year october, 2010. I will keep you informed.
All the best, keep in touch
Alexandra Gaba-van Dongen
Curator
When I was in Sweden in 1974, I was at the lake known as Storaven as part of a archaeological team. Our Lappish hosts cooked coffee in a three legged pot that was standing on coals on the beach. The three legs allowed the pot to stand on uneven surfaces and still be level.
My thought on this subject, IMHO, is that if people were smart enough to create legged pots, then when a leg was broken off, they would repair the pot by replacing the leg. You would not throw out a perfectly good pot.
As for putting a legged pot on a table, especially if that table was wood, a pot that had come directly from the coals would create three burn spots in the table. When I cook with a "spider" (three legged pan), I use a ladle or spoon to serve directly from that pan. If a pan had no legs, I would use a "trivet" on the table to hold the pan above the table surface thus avoiding possible burn spots on the table. This topic is interesting as I do historic demonstrations and cook with a pot over open fires.
Thanks for the initial post! It gives me something to think about.
Charles Butcher mentioned finding diamond-shaped rivets. Are these rivet blanks? At one site I have found numerous small 3/4-inch diamond-shaped pieces of hand-cut sheet copper alloy, perhaps cut from kettles. I am trying to determine if these blanks are typically French or English, or both. At what other sites are they found?
And where would I be able to purchase a pot like the one pictured above. I simply looove it!!!