Oberaden Pilum. a thought...

[Hibernicus]

I'm in the process of making several wood Oberaden pilum shafts...
museums.ncl.ac.uk/archive/arma/images/welc/begin/pilum.gif

I'm also making lead weighted pilum shafts, casting the lead directly onto the wood shaft.. have done a few and am getting better at it.... In order to insure that the lead weight does not slip off the shaft I carve two concentric rings, "V" shaped grooves around the shaft, that the edges of the mold fits snuggly into. The slope of the "V" is shallower on the lead weight side, the idea being that if the lead is slightly recessed into the wood it is less likely to slip off.

So here I am carving the Oberaden "bulb" right below the pyramidal head of the wood shaft and it strikes me.... the bulb is designed to have a lead weight cast around it!

What a clever way to insure that the lead weight does not slip, what a clever way to use a bit less lead.

Your thoughts?


'

[Gaius Julius Caesar]

Also does not introduce a couple of weak points into the Shaft?



B. Angel

[Martin Moser]

Actually, my first thought when I saw that pic was that if this pilum hits anything hard, that's where it'll break.

Interesting thought about the lead, though!

[Matt Lukes]

Well the blocks of the other two pila are just as long as this one, but without the deep incision- so is there any real reason to assume the incision is an original feature and not just a result of degradation or some other 'artifact' of its preservation? That's what I'd always taken from the diagram myself- given that the portion below the incision continues the same taper, edges, etc.

[Hibernicus]

Martin:

Actually, my first thought when I saw that pic was that if this pilum hits anything hard, that's where it'll break.

My thought as well.

I'm going to cast a lead weight around the Oberaden bulb

I'll give that one and an Oberaden without a lead weight a few hundred tosses and see what happens.

[Matt Lukes]

An answer for Martin but none for me? :lol: Here are all three Oberaden pila- clearly only one has that strange groove and again if you follow the lines, this supposed bulb comprises the perfectly normal base of a pyrimidal block, suggesting that the groove could-well be an artifact itself- i.e., not an original feature.

Anyone know if this is the one that survived the war? I'd think that there should be significant evidence of lead were this actually a weighted pilum. Especially since I think they're only theoretical, based on sculpture (yes?), identifying such a piece would be a significant discovery and surely would have been mentioned.

[Tarbicus]

Given the amount of smoothing/erosion on the rest of the pilum, couldn't the groove have just been eaten away more than the rest over the centuries, it being a natural conduit or channel for whatever it is that does this to wood? There's definitely a groove there, but it may not have been nearly as deep as what we see now.

[Matt Lukes]

Of course that having been said, I do see how it can be considered that the lead weight might have been cast over lower portion of the pyrimidal block- the sculpture below certainly does appear to show the block emerging from the weight as opposed to the weight just being behind the block. It does also show that the bottom end of the weight has some kind of 'studded' ring below it and the wrapping of the shaft plus that look to be candidates for how the weight is held in place as well... although I have no explanation for the strange incised portion of the block with an axial ridgeline hock:

[Matt Lukes]

Given the amount of smoothing/erosion on the rest of the pilum, couldn't the groove have just been eaten away more than the rest over the centuries, it being a natural conduit or channel for whatever it is that does this to wood? There's definitely a groove there, but it may not have been nearly as deep as what we see now.

That's how the artifact always struck me Jim- especially given the otherwise matching (more-or-less) size, etc. to the other two artifacts. Hence my question of whether or not anyone knew of a good reason to think the groove might be an original feature. I wouldn't dismiss the idea out of hand of course, but there'd have to be some evidence to support the suggestion that it was intentional.

Are there any photographs of the piece? These diagrams are nice, but don't sufficiently show the details- for example, we don't know if there's any staining to suggest association with another material that could have caused selective erosion, or if there might have indeed been some lead there. Hell, some diagrams make it look like two fragments, not a single one with a groove :lol:

[Tarbicus]

It does also show that the bottom end of the weight has some kind of 'studded' ring below it and the wrapping of the shaft plus that look to be candidates for how the weight is held in place as well...

Nails?

[Matt Lukes]

I thought of that at first too, but nails would weaken the haft and make it more susceptible to breaking. Given the light incised 'decoration' on the weight itself, this feature could even be part of the lead casting- who knows? This is the only representation of 'weighted' pila I'm familiar with, and although it's quite nicely detailed, suggesting less artistic license, without more examples to compare it to, we're left somewhat stuck.

[Matt Lukes]

Okay, I just checked and Connolly states in his article The Pilum from Marius to Nero that this is indeed the one pilum that survived the war "reasonably intact", and that in 1942 photographs were published, however there were no analytical drawings made- the ones we have of the two that were lost must have been done from the photos.

There's also a second diagram of the opposite side of the artifact to the one shown above- clearly the 'groove' is not circumferential, but rather that's how the slightly angled 'front' diagram makes it look. The portion below the groove is clearly not a bulb, but the base of the pyrimidal block. Given how the broken end of the shaft is rounded, it's likely the bottom corners of the block were likewise rounded over time. Also note that there's a significant groove from the collar to the lower tang rivet- but only on the back side- I can't see how that could be intentional, so it could-well represent more odd selective degradation of the wood.

Indeed grooves on only two sides of the block would constitute good hold for a lead weight, but given how they look, I'm far less-inclined to consider the theory as viable- unless there's some evidence of residual lead on the base of the block. If one had been cast in place, there'd certainly be that in the wood- even and especially if the weight had been melted off to reclaim the lead or if it had somehow degraded over time. Of course the latter seems highly-unlikely given that the iron and wood portions survived remarkably well, and any conditions that I can think of that would result in the complete degradation of the lead would certainly have a significant effect on the wood and iron as well.

[Caius Fabius]

I don't know about your lead temperatures, but when I am casting lead, it is usually hot enough to char wood, when it comes in contact in a molten state. You might see evidence of charring, if the lead was poured into a mold and was coming directly in contact with the wood before it cooled.

[Hibernicus]

Of the three I believe that one has a groove on one side, another has no groove and the third has a groove that goes all the way around.

The pic of the carved pilum... the sphere that appears to have been formed over the bottom of the pyramidal shaft head... that's the one I remember.. I knew I'd seen it before just couldn't remember where/when. .. thanks! Do you have a site reference for it? That'd sort of thing would be very useful.

And of course there wouldn't have to be any residual lead... if the weight had yet to have been cast around the shaft.

[Matt Lukes]

hock:

Doesn't the lesion on the left side of the first artifact look a whole lot more like damage than an intentional groove? It's jagged. Look at the diagram- the end of the shaft is jagged too- if one were rounded and the other jagged, I might wonder why they're different, but they're not. What's more, the damage is at the level of the bottom tang rivet- hardly a smart place to intentionally groove the block.

And the second diagram I posted- the opposite side image of the third artifact-clearly shows that the groove does not go all the way around. It's a groove across two opposite sides, and it's the angle of the initial side that seems to show the groove going all the way around. If it went all the way around, the lines of the outer edges wouldn't be continuous from colette to base- there'd be indentations at the line of the groove.

And yes there wouldn't be any lead residue if the ball hadn't been added yet, but isn't even more of a strectch? I mean the pilum is complete in every other respect- wouldn't it make a whole lot more sense to add the weight before installing the shank? There's no evidence whatsoever that the groove is even intentional, and without any evidence of lead, there's simply no support for the idea- save that it might kind of look like a sculpture that is more different than similar.