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by zeusdclxvi 84 days ago
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
2 comments

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

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

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...

Weirdly, not available in the USA :(
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.
> 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.

> 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.

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?

If the time and accuracy comparisons are unfair, then they shouldn't have been made in the first place. Being corrected on a claim that isn't true isn't grounds for outrage.

What I wrote was factual; there are all sorts of reasons to use such machines other than being faster and more accurate than the best human archers, but it still is not correct to claim that they are.

> What I wrote was factual;

I disagree; I didn't say that it was less accurate than archers, I said that it was less accurate than a #1 ranked archer in the world.

IOW, this machine is faster than a #1 ranked archer, while being almost as accurate (15 arrows/target) vs 11 arrows/target.

What you wrote implied that this machine was less accurate than archers, not less accurate than a #1 ranked archer. I don't think that the skill level of archers are all clustered around the top. It's more likely a bell curve so the clear majority of archers are going to be both slower than and less accurate than the machine that was tested.

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.
I didn't claim there was no advantage; I said the advantage wasn't accuracy.

It doesn't seem like you disagree with me here, but you've phrased it as though you do.

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).
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?
You can't imagine why a quick succession of bolt fire might be more advantageous than a slow reload?
I mean how is it actually faster if the rate limiting step is the same. People are claiming it was 2-3X as fast.
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.

Yeah, I was thinking maybe the entire speed advantage was the windlass and had nothing to do with the auto bolt feeder.
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?
Even a short surprise can be crucial in an ancient battle, where breaking formation can be fatal
Breaking a calvary would be very powerful. And horses are a larger target.
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.
Very likely.
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).

Pulley and a big rock to precharge. We know they had the components since catapult existed.
They had the components for a crude steam engine. That isn't proof they did it.
The psychological advantage can't be discounted either
Maybe one less operator required? Less chance of losing a hand?
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.