Catapults versus Trebuchets

[Eleatic Guest]

Traction trebuchets replaced torsion catapults after antiquity because they were easier to built and maintain. Yet, one of the advantages that catapults kept was range. This video made me think that ancient catapults could have retained a useful role as counter-battery fire even against the late medieval counterweight trebuchet. As you can see, the trebuchet has to be positioned quite close to the wall, only around 150-200 m.

This makes it vulnerable to counterfire: Archers, crossbowmen and arrow-firing machines could disrupt its crew and set the wooden trestle on fire. But stone-throwing catapults could hope to outright destroy the machine. They could be positioned outside its range, within the walls if necessary, and could throw stone balls from the safe distance. Yet, in the Middle Ages only the onager is attested, and I have not come across evidence for such a deployment. Any thoughts why the idea never seemed to have occurred to medieval defenders?

[Sean Manning]

Traction trebuchets replaced torsion catapults after antiquity because they were easier to built and maintain. Yet, one of the advantages that catapults kept was range. This video made me think that ancient catapults could have retained a useful role as counter-battery fire even against the late medieval counterweight trebuchet. As you can see, the trebuchet has to be positioned quite close to the wall, only around 150-200 m.

This makes it vulnerable to counterfire: Archers, crossbowmen and arrow-firing machines could disrupt its crew and set the wooden trestle on fire. But stone-throwing catapults could hope to outright destroy the machine. They could be positioned outside its range, within the walls if necessary, and could throw stone balls from the safe distance. Yet, in the Middle Ages only the onager is attested, and I have not come across evidence for such a deployment. Any thoughts why the idea never seemed to have occurred to medieval defenders?

Stefan, I think we do hear about shooting at the attackers' engines in sieges in the second half of the middle ages. That was one thing that the bolt-throwing bow and skein artillery ("springalds and great crossbows") were for but I could swear I remember stories about defenders hurling stones at siege towers with trebuchets sometime around the 12th century.

What medieval evidence for Ammianus' one-armed, stone-throwing onager do you know?

I am not sure how the range of different stone-throwing engines compared to one another, but I would love to hear about experiments. Bigger engines are harder to test because they are more expensive to build and more dangerous to operate. PBS Nova: Secrets of Lost Empires: Medieval Siege had a big budget by humanities standards!

[Ildar]

Yet, in the Middle Ages only the onager is attested, and I have not come across evidence for such a deployment.

Stefan, it is a myth. There is no evidence that the one-arm torsion stone thrower ever existed in the Middle Ages. See Peter Purton's and my articles.

[Eleatic Guest]

I am still under the belief that I saw an onager in a late medieval technical treatise but I cannot track it down anymore. So, yes, maybe myth alarm.

[Eleatic Guest]

Yet, in the Middle Ages only the onager is attested, and I have not come across evidence for such a deployment.

Stefan, it is a myth. There is no evidence that the one-arm torsion stone thrower ever existed in the Middle Ages. See Peter Purton's and my articles.

It is your fig. 4. no. 1 I meant.

[Sean Manning]

is this the manuscript you want? ÖNB, Wien, Cod. 3069 from Schloss Ambras like all the classy things http://data.onb.ac.at/rec/AC13934231

There are scans at http://data.onb.ac.at/rep/1001EF8B

The clothing etc. are perfect for 1411. I don't know of any tests of any of the kinds of medieval skein artillery, it would be a great project for someone crafty with a big piece of land or a pickup truck.

[Ildar]

I saw an onager in a late medieval technical treatise

Stefan, the illustrations from Kriegsbücher don't support the existence of the onager in the Middle Ages, as I already wrote in my paper, because "apart from illustrations in some Late Medieval engineering treatises, a vast array of other illuminated manuscripts does not have any illustrations of one-armed torsion engines, whereas the illustrations of traction and counterweight trebuchets, crossbows, bombards etc. abound."
These illustrations go back to two or three prototypes only, so there is strong probability that they could be redrawn from the same now lost ancient treatise. Besides, many of these illustrations have details, which were well known in antiquity, but were hardly possible in the Late Middle Ages.

[Sean Manning]

Of course, most of the standard history of catapults (the one I criticize in chapter 6 of my PhD thesis) is based on one passage in Diodorus and another passage in one of the manuals for catapult-makers, both written hundreds of years after the events they describe (and Diodorus' history of siege engineering is as partisan as the grape farmer's history of land warfare).  Ancient bow artillery, for example, is known from a single manuscript, but it was probably the most common type in the 5th and 4th centuries BCE.  And the material culture in that manuscript is, at first look, perfect for 1411, its not the usual "20-40 year old stuff so they will know this is olden times."

So I find those manuscripts good evidence that there were one-armed skein catapults in Austria in 1411, but I would like to see supporting evidence such as an account with an entry "100 stones for springalds, 12 s. 2000 bolts for arbalests, 20 s."  Weak evidence is not no evidence.

Could you explain how a cast bronze washer was "was well known in antiquity, but was hardly possible in the Late Middle Ages"? This is a culture that produced clocks, automata, giant guns and bells, and suits of articulated steel armour, they could do mechanics.

And if it made sense to experiment with two-armed torsion engines in the 13th century, even though they had trebuchets and great crossbows, why wouldn't it make sense to experiment with one-armed engines in 1411, even though they had trebuchets and great crossbows and guns? Saying that we have some evidence for a type of machine in the 15th century is not saying that it existed a century earlier or that it was common.