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Pompeii's battle scars linked to an ancient 'machine gun'

104 points by pseudolus 5 days ago | 37 comments

The polybolos was an advanced ancient Greek repeating ballista, often described as a "machine gun of antiquity," invented in the 3rd century BC by Dionysius of Alexandria. It used a unique chain-drive and gravity-fed system to fire bolts in rapid succession

mkl 18 hours ago

https://en.wikipedia.org/wiki/Polybolos

Apparently it was on MythBusters, but I don't remember that one.

josefx 17 hours ago

Could it be this one? https://www.youtube.com/watch?v=IN-V3nUCvpI

Springtime 14 hours ago

Matches the name of episode 152[1] the Wikipedia article cites for the info. Seems the classification of seasons and even the season's episode order on Wikipedia differs from the one in the Youtube title.

[1] Text-based summary: https://en.wikipedia.org/wiki/MythBusters_(2010_season)#Epis...

lloydatkinson 11 hours ago

https://youtu.be/IN-V3nUCvpI?t=2733

zadikian 17 hours ago

I've heard of this, but what's the advantage? They still need to recharge the torsion the same way, which must've taken longer than someone manually feeding the next bolt.

lelanthran 14 hours ago

> I've heard of this, but what's the advantage? They still need to recharge the torsion the same way, which must've taken longer than someone manually feeding the next bolt.

https://en.wikipedia.org/wiki/MythBusters_(2010_season)#Epis...

> They set up 5 targets at 90 yards (82 m) and brought in professional archer Brady Ellison to provide a benchmark for comparison. He hit the targets in 2 minutes, using 11 arrows. After further breakdowns and repair work, Adam and Jamie accomplished the feat with 15 arrows in 1 minute and 50 seconds.

Certainly sounds like a win to me, if it was faster and just as accurate as the worlds number one ranked recurve archer :-/

You can train a man to turn the windlass in about an hour. It takes years to get an archer to the same accuracy and speed.

So, a definite advantage.

Peritract 10 hours ago

> He hit the targets in 2 minutes, using 11 arrows. After further breakdowns and repair work, Adam and Jamie accomplished the feat with 15 arrows in 1 minute and 50 seconds.

Faster, sure, but not more accurate--10 seconds less but 4 more arrows. Faster itself is also debatable, depending on whether or not you factor in the breakdowns.

b112 9 hours ago

Breakdowns aren't relevant, as Mythbusters slapped it together over a few days, and are uncertain of the design. The Greeks had years to perfect it, and great knowledge and expertise building with these materials.

As another poster mentioned, the time comparison is unfair too.

In terms of accuracy, how many days or weeks did they spend learning the tool?

estimator7292 2 hours ago

The advantage is you don't need very valuable people who have been training their whole life. Even if the machine is only half as good as the empire's best archer, you can have as many as you want as quickly as you like, and they still perform better than grabbing some rando off the street and slapping a bow in his hand.

zadikian 5 hours ago

I mean against a ballista that's the same thing but without the automatic bolt feeder that makes it a "machine gun." Against an archer, I'm not surprised, but that was the advantage of a regular ballista too (and later crossbows).

bondarchuk 13 hours ago

From wikipedia it sounds like the advantage is not really speed of recharging but just that it will repeatedly fire for as long as the lever is turned without any other actions or pauses needed in between. Maybe not losing 10% (or whatever?) of the time on bolt feeding was sufficient advantage? Maybe the ease of operation in a hectic battle situation was advantage enough? Or maybe the continuous power requirement made it more feasible to use multiple soldiers at once working at higher speed, without them having to synchronize starting/stopping/waiting every x seconds?

avadodin 12 hours ago

Full auto would require charging a huge version of a similar mechanism for a single volley and as a non-actual-engineer, I do not know that it is possible to output the torsion energy in a controlled manner preventing the gun from exploding violently.

edit: But, yes. This is more akin to a revolver than to a machine gun(or even chain gun as Wikipedia implies).

brador 11 hours ago

Pulley and a big rock to precharge. We know they had the components since catapult existed.

IAmBroom 4 hours ago

They had the components for a crude steam engine. That isn't proof they did it.

bfivyvysj 17 hours ago

You can't imagine why a quick succession of bolt fire might be more advantageous than a slow reload?

zadikian 17 hours ago

I mean how is it actually faster if the rate limiting step is the same. People are claiming it was 2-3X as fast.

Someone 15 hours ago

Reading https://en.wikipedia.org/wiki/Polybolos, at least some of these used a windlass to rearm. That may explain part of the speed difference over one using a separate lever or one that’s rearmed purely by hand.

These weapons also may have given up on some firing power for firing frequency.

zadikian 5 hours ago

Yeah, I was thinking maybe the entire speed advantage was the windlass and had nothing to do with the auto bolt feeder.

eucyclos 16 hours ago

Maybe it's harder to deal with ten projectiles in a minute followed by a nine minute reload than one a minute for ten minutes?

ithkuil 16 hours ago

Even a short surprise can be crucial in an ancient battle, where breaking formation can be fatal

b112 9 hours ago

Breaking a calvary would be very powerful. And horses are a larger target.

zadikian 16 hours ago

I'm not even considering the magazine reload time, just the time between shots assuming a full mag. That's 10 recharges either way, as shown in the videos. It's not like a machine gun where the energy is in the powder.

goodpoint 14 hours ago

Very likely.

adzm 16 hours ago

The psychological advantage can't be discounted either

normie3000 17 hours ago

Maybe one less operator required? Less chance of losing a hand?

zadikian 16 hours ago

Yeah I figured it's more convenient, but they're claiming it's also twice as fast.

With the chu ko nu I get it, you only have two hands, so the auto reload was faster.

IAmBroom 4 hours ago

Chu-Ko-Nu:

https://en.wikipedia.org/wiki/Repeating_crossbow

PhunkyPhil 7 hours ago

Slightly off topic, but when I read about these archeological discoveries being made thanks to custom software, ML or the like - Who is writing this code?

To me these projects would be so fun to work on, but this domain seems so far out of a tradition SWE track. Are the researchers just cobbling the code together themselves? Cross department collaboration within the university? I'd love to have a hand in things like this.

trgn 5 hours ago

i rolled into tech because of archeology. started using GIS for site mapping and need for customization just got me going. ended up going to school again for compsci.

generally, students from other departments are writing the code, but current day most archaeologists can work with ready-made packages (model builders etc..) now too.

sebastianconcpt 8 hours ago

What's the proof for succession?

How was discarded that the impact were simultaneous instead? Like spreading from a catapulted bunch of pellets?

zadikian 4 hours ago

Guessing the holes are too small and deep to be pellets, and there wasn't a recorded machine that fired multiple bolts simultaneously.

peet2521 6 hours ago

Came to the comments with the same question as you. I'm pretty sure the answer is that it almost certainly was a bunch of small projectiles hurled simultaneously, but that wouldn't be interesting enough to even write an article about.

I'm pretty sure this isn't even written by a human, it's deliberately inaccurate infotainment LLM slop.

rc_mob 8 hours ago

the ads on that article make it unbearable to read

metalman 13 hours ago

likely would have had tactical utility to take out one select high value target especialy against an oponent who had not encountered it. so more of a battlefield assination weapon. it also decouples the need to have great physical strength ,and visual acuity

bamwor 9 hours ago

[dead]

JKCalhoun 9 hours ago

I not often cynical, but I confess to being uninterested in the "dead ends" of history. Perhaps these are areas though where a historian (or layperson) might find rich for "what if" speculation. For me it's more like if a tree falls in the woods and no one is there to hear it…

The Antikythera mechanism is another one that is uninteresting to me because, whatever it is, it seems to have been a one-off.

Maybe, like James Burke's obsession with "connections" in history, I am drawn instead to historic through lines.

user_7832 7 hours ago

(I know this isn't exactly your intention, but it's a similar situation.)

Do you think that we should give funding to study the mating habits of endangered iguanas in the Sonoran desert, or should we be funding cures for alzheimer's and diabetes?

Trick question, it's the same thing!

Science often finds weird things in weird places.

Shamelessly plagarized from this tumblr post:

https://i-draws-dinosaurs.tumblr.com/post/811645777885741056

dndkdkdkdkdk 8 hours ago

[flagged]