Xanten Manuballista

[Caivs Marivs Scipio]

Last year Pax Romana, together with Len Morgan (XIIIIth GMV) and the Ermine Street Guard reconstructed the small Xanten manuballista, as found in 2004. The first reconstruction of this piece of artillery in The Netherlands.
We would like to say a special thank you to Alexander Zimmerman (LEG VIII) for the basic information. Also we recieved extra information from the Dutch conservator of the ballista, who pointed out some interesting facts.

In the reconstructions made by Alexander and LEG XII Primigenia was chosen for a handheld ballista. Based on the information from the conservator we have chosen for a tripod mounted manuballista.
The manuballista isn't that big and the weight seems to be bearable, but it is still to heavy to use accurately for some time.
Because the manuballista was found in the Rhine near Xanten it could very well be a naval manuballista, from the deck of a ship.
In case of the reconstruction with tripod it could easely be used on board of a ship or in the field, and would be very mobile with a one or two man crew.

During some of our last shows last year we demonstrated the reconstructed manuballista to the audience. Though the torsion springs are not yet fully torsioned, we easily managed to hit the target over a 70 meter distance.

_________________
GAIVS MARIVS SCIPIO / Sander van den Brink
Pax Romana (NL)
COH·XV·V·C·R
CLASSIS·AUGUSTA·GERMANICA
ALA·BATAVORUM

[url:1usfxgo0]http://www.paxromana.nl[/url]

[Robert Vermaat]

we easily managed to hit the target over a 70 meter distance.

I didn't.

Very nice machine, btw.

[Gaius Julius Caesar]

Last year Pax Romana, together with Len Morgan (LEG VIII)

Len Morgan is with the XIIIIth GMV...

[Caivs Marivs Scipio]

Last year Pax Romana, together with Len Morgan (LEG VIII)

Len Morgan is with the XIIIIth GMV...

Woops! :oops: But changed!

we easily managed to hit the target over a 70 meter distance.

I didn't.

Well, it was close enough for a first time! 8)

[D B Campbell]

Very nice catapult.

Today, I received a copy of Xantener Berichte Band 18: H.-J. Schalles (ed.), Die frühkaiserzeitliche manuballista aus Xanten-Wardt (Zabern: Mainz, 2010). I am sorry to see that, in the book title, they have (erroneously in my opinion) labelled the machine as a "manuballista"; however, in the articles within the book, it is labelled (more correctly) as a "Torsionswaffe" or "Torsionskatapult".

[Caivs Marivs Scipio]

That would indeed be more correct than Manuballista.
Maybe we should just call it a Scorpio? In fact, that's what it is...

[D B Campbell]

In fact, that's what it is...

Yup.

[AuxArcher]

Nicely made machine.

If you don’t mind, could you give us some details into the performance of this machine? Do you have access to a chronograph and can give us some hard numbers on arrow / bolt velocity, for instance. How flat a trajectory are you getting with this machine? What type of bolts are you using, what length, and what types of heads (and weight of heads)? Do the bolts wobble in flight or fly true as they leave the “muzzle” end? What types of shot groupings are you getting at a given range? How deeply does a bolt penetrate a target at a given range? Do the bolts penetrate armor or shields? Thick clothing, subarmor? Human flesh and bones, of course, and major organs or arteries for quick bleed out.

And, what estimate do you have for strength of pull at a given draw length? 100 lbs, 200 lbs. 500 lbs.? I assume since you added a winch, you wanted to gain relatively high pull weights. If the Xanten machine was a belly cocker (speculation of course since only the spring frame still exists), what justification do you use to add a winch?

How heavy is the machine – how much does it weigh? You alluded that it is too heavy to operate without a tripod. Do you mean it is too heavy to shoot without support, or too heavy to carry around for long periods of time in field conditions? Would it have been as heavy for a Roman soldier vs. most of us who live much less physically strenuous lives?

Out of curiosity, is 70 meters the maximum range that you can hit a target with accuracy? That doesn’t seem to me to be a very impressive number, but maybe you are still learning to shoot it? Since it is mounted on a substantial base, you should be able to do better relatively quickly with such a steady mounting platform. Sandbagging the machine on a range shooting bench or otherwise stabilizing it through multiple shots may give you a much better idea of the potential of this machine.

Have you tried flight shooting it, to see what maximum range is yet?

Your comment about naval application of this weapon was interesting. My understanding is that exposure to moisture is detrimental to sinew spring performance, and a machine permanently assigned to a ship or patrol boat (if that did happen at all) would suffer significantly in performance. Do you happen to know if Greeks and Romans utilized either torsion or tension machines on warships at all? Because of space issues, I imagine archers being the best missile troops for classical period naval ships. Rivers are major trade and transportation routes, so the Xanten machine being found near the Rhine to me doesn’t automatically rule that the original machine was even used for waterborne operations.

I hope you can answer my questions. Performance questions are much more interesting and valuable to me than speculation, in any case. Forgive me if there are so many. And, happy new year.

Dane

[P Sertorius Scaevola]

It would appear the input on behalf of PR is 'debatable' to say the least, with Len Morgan and Tom Feeley of the ESG being the people actually doing the practical research and production of the ballista. Nevertheless it is nice to see that another machine is available for public view.

[D B Campbell]

Len Morgan and Tom Feeley of the ESG being the people actually doing the practical research and production of the ballista.

If you're referring to the Xanten "ballista" (or scorpio), the research has been conducted by Hans-Joachim Schalles and the best-known reconstruction (from its appearance on all of the publicity material) was made by Alexander Zimmermann.

But maybe you're referring to a different ballista?

[P Sertorius Scaevola]

You're correct there Duncan, I was aiming at this particular reconstruction, not the Xanten machine itself. Merely trying to point out that the road had already been largely paved prior to the birth of the ballista that's subject to this discussion. Showing off with other people's efforts is below this forum's nature. Eager to learn though if the boast can be backed with facts.

[Anonymous]

Dear Duncan,

I am sorry but I disagree. Of course, I know that literal sources for the term manuballista date back just to late-antique times. But ist there any better description for this kind of weapon? The Xanten find is small and 'hand-held' (manus), it is not a machine like Ampurias or Caminreal. And it is a catapult (ballista).

Kind regards,
Hajo Schalles

[Moderatus]

Duncan is absolutely correct to call the Xanten-Wardt machine a scorpio. At the time of the Xanten-Wardt catapult, ballista was used exclusively for the stone-thrower. The description of this machine as a manuballista (hand catapult) in the title of the Xanten-Wardt report, and by some of its contributors, is incorrect, because that term belongs not to euthytone frame bolt-shooters like the Xanten-Wardt, but to the later design of palintone bolt-shooter with an arch strut metal frame first known from its appearance on Trajan’s Column in the Dacian campaign of AD 101-2. The palintone design of frame was borrowed from that of the standard wood frame stone-throwing ballista described by Philon, Vitruvius and Heron, and this may well account for the change of terminology that switched the term ballista to the arch strut palintone design, as carroballista or manuballista.
While the term scorpio was sometimes used in a general sense as an alternative to catapulta, it was frequently applied to the smaller sizes of bolt-shooting catapultae. The historian Livy lists ballistae and large catapultae amongst the booty taken by Scipio Africanus in Hannibal’s base at Cartagena; he also records”a vast number of larger and smaller scorpions and armour and weapons”. The distinction which Hellenistic and Republican writers made between the larger sizes of bolt-shooters and scorpions is maintained by Vitruvius who talks about the tuning of catapultae, scorpiones and ballistae. In his eyewitness account of the sieges of Jotopata and Jerusalem, Josephus uses a pair of Greek words for bolt-shooters, katapeltai (= catapultae) and oxybeleis (”sharp-firers” = scorpions). There is good evidence to identify the Three-span bolt-shooter as the scorpio maior (larger scorpion) and the One-cubit (Two-span) as the scorpio minor (smaller scorpion).
The clearest evidence is found in Philon’s discussion of the choice of size for Dionysius of Alexandria’s winched, stand-mounted, torsion repeating catapult: he calls it a skorpidion, a small scorpion, “not much larger than a One-cubit machine, and not much smaller than a Three-span.” Both sizes are by implication winched, stand-mounted scorpions. A Three-span scorpion had a spring-hole diameter of 4 Greek dactyls = 77 mm and a bolt 36 dactyls = 69 cm long. A One-cubit or Two-span machine had a spring-hole of 22/3 dactyls = 51 mm diameter, and a bolt 24 dactyls = 46 cm long. Philon states that Dionysius’ bolt was only one dactyl longer than that of the One-cubit machine at 25 dactyls = 48 cm long. In comparison the Xanten-Wardt torsion catapult has a spring-hole diameter of 21/3 dactyls = 45 mm, and a bolt 9 x 45 mm = 40.5 cm long. This makes it slightly smaller than a One-cubit/Two-span, as a One-and-Three-Quarters-span.
The interpretation of smaller torsion catapults as stomach-bows lacking a winch and stand was sparked off by Dietwulf Baatz in his 1974 Saalburg Jahrbuch article on the finds from Gornea and Orşova, and repeated in his 1978 article in Britannia. It contradicts Heron of Alexandria’s authoritative statement, in his description of the development of artillery, that torsion catapults developed so much power that the stomach-bow’s withdrawal-rest had to be replaced with a winch, with a pulley-system added for the larger machines. Baatz later told me in a letter that his interpretation is based on the theoretical possibility that a Roman engineer could have picked up the idea of loading by stomach pressure from Heron’s description of the early Greek stomach-bow, and applied it to a small torsion catapult.
Irrespective of the above evidence for the Smaller Scorpion torsion catapult as winched and stand-mounted, the complete survival of the wood and metal of the Xanten-Wardt frame enables fully accurate replicas to be made, and settles the argument. There are now three copies of our Xanten-Wardt reconstruction in use by re-enactment groups, two in Britain by the Roman Military Research Society and the Ermine Street Guard, and another in Holland fielded by Pax Romana. They have been made with millimetre accuracy by Len Morgan and Tom Feeley from the official plans, and with help, through Maarten Dolmans, from Alexander Zimmerman and restorer Jo Kempkens. The arms, winch and stand are derived from Vitruvius’ description and measurements (we are in the process of manufacturing the curved arms described by Vitruvius). The simple, critical test is to discard the support stand and then attempt to hold the weapon steadily in the aim; next try loading it by stomach or muscle power, inserting the bolt, lifting it back into the aim, all this time and time again as required on the battlefield. To do this for any length of time without a support stand is impossible. The point of balance is immediately behind the frame. With a stand and levered winch, operators of whatever stature and muscle power can keep reloading and aiming for indefinite periods. The use of the support stand meant that the first two hours of continuous shooting trials of my personal copy of the reconstruction could be carried out by my two friends Tom and Eleanor aged twelve and ten, who put on a display of very accurate shooting; of course in their case the pullback was reduced for safety reasons.
The above line of argument and evidence for the Xanten-Wardt torsion catapult and those of similar calibre as Smaller Scorpions with winches and stands does not appear to be given space in the Xanten-Wardt report. The end of the report presents the reader with a curious reconstruction as a hand-held catapult loaded by pressing the extended slider vertically down into the ground, apparently using the weight of the machine plus downward pressure by the operator. There is a ratchet track mounted out of sight underneath the slider, a misinterpretation of the surviving remains of the stock and slider, and a system for which there is absolutely no ancient evidence. The photographs of it being aimed show a reenactor holding the stock with his left hand, with a curved shoulder-piece resting against his right shoulder; he has to take the weight of the weapon by raising his left leg onto a large box, and supporting his left elbow on his left knee. This strange box support system confirms that there is a weight problem. The vertically mounted shoulder-piece cannot be used to apply stomach pressure. If the contributors to the Xanten-Wardt report believe the catapult to be a crossbow, why did they not reconstruct the stock from Heron’s clear description and diagram of the stomach-bow, using side ratchets and the curved horizontal withdrawal-rest with end handles?
“The object of artillery-construction,” states Heron, “is to project a missile over a long distance at a given target and deliver a powerful blow.” Philon advises, “We must direct most of our research, as we have frequently emphasised, to achieving long range and to hunting down the features of engines which lead to power.” A stomach-bow can only generate a fraction of the power of a winch, and cannot fulfil the requirements of these definitions.
Most of the Xanten-Wardt report is rightly devoted to the details of the long and painstaking recovery of the machine from its coffin of solidified sand, grit and pebbles. X-rays and CT scans were used to locate the buried parts, in order to guide the delicate task of removing the concretion. I would like to record our admiration for the work of the team of specialists involved. Exemplary is hardly a strong enough word for this superb, patient work of rescue, analysis and conservation. This is by far the most important discovery made to date in the long search for the remains of Greek and Roman artillery.

[P Sertorius Scaevola]

Thanks Alan for a truely wonderful in depth explanation on the ins and outs on this particular machine. I particularly liked the field testing with aid from the juvies!