05-04-2009, 06:57 PM
derek forrest\\n[quote]Yes we have 2 3 spanners in wood but we have no record of metal frames before Trajan's column. I have argued that there must have been a development period as the Cremona 3 spanners were 30 odd years old but the committee remain unconvinced and short of some more finds with coins on top we are in difficulty. [quote]
Derek,
I agree with you that iron-framers must certainly have pre-dated their appearance on Trajan's Column. There are two major factors which support this assumption. The first is plain old military logic. It would be folly for a Commander to take a new and untried weapons system on campaign without traditional sytems to fall back on. Unlike the rash Domitian, Trajan was described as militarily astute, so the absence of tried-and-true wood-framers suggests that ferroballistae were sufficiently assimilated and/or provided such superior performance that wood-framers were not needed. The second and more direct source is Cassius Dio. In his description of a battle near the end of Trajan's First Dacian campaign he writes..."Trajan seized some fortified mountains and on them found the arms and the captured engines, as well as the standard which had been taken in the time of Fuscus." Dio p377
Since the engines shown in posession of the Dacians on the column are iron-framers, that strongly supports the existence of ferroballistae in regular field use as far back as 87-88 AD. Let's see if we can come up with a scenario/timeline, supported by the evidence, that can explain the disappearance of the wooden dinosaurs.
@25 AD Vitruvius writes his difinitive text on catapults. The salient features this eras weapons are;
Circular ratchets and drum type winches which have replaced the earlier linear ratchets and turnstiles.
A progressive trend toward shorter side stanchions for a given washer diameter (ie.underspringing compared to his formulaic ideal) as evidenced by the Ampurias, and Caminreal frames.
A tripod-type base with a separate backstay that has a hinged prop and socket (chelonium) to keep the case at waist level while one is winding the winch.
@50 AD Xanten The frame of a small wooden engine is found. It is small enough that it was likely a hand-held scorpio minor. It's most interesting features are;
A narrow single-arched (not palladian-shaped like Caminreal and Cremona) aperture, and a frame that it appears taller/narrower (oversprung) compared to Vitruvius' ideal ratio. This implies shorted arms and a correspondingly shorter draw length which would be useful on a hand-held weapon. On a stand mounted weapon draw length is not as much of a factor.
60-70? AD Heron of Alexandria The real guy, Edison of his era, and most likely candidate to invent something this novel. Writes about a new way of building a hand-held ballista using metal "field frames" spaced widely apart so that the arms can now swing inwards past each other. He doesn't bother to include instructions for building a winch or stand because as a hand-held, manually-spanned weapon, it doesn't need them. It's a cool idea, but underpowered for military use and won't yet supplant traditional weapons like Xanten.
69 AD Cremona Washers and a battleplate for a weapon are found (or should I say lost). The aperture is palladian-shaped and using the battleplate as a guide it is even further undersprung than Ampurias or Caminreal. By Vitruvian standards such an engine would need even longer arms and a longer case to compensate. Curiously, the aperture is offset upwards in the frame. This implies that the case and canalis funduswere similarly offset causing the string to ride directly on the "slider" above the plane of the arms. This is not really a problem since it is similar to the earlier gastraphetes and later crossbows. Moving the frame down (let's call it underslung to stick with the theme) makes it easier to aim over the hole carrier.(just for those "field of view" lovers out there :wink: ). The Cupid Gem is of indeterminate age, but I choose to place it here with Cremona or slightly before, but certainly sometime after Vitruvius. The initial reason for that was that, like Alan Wilkikns, I saw its "Itallic A" shaped base as a close relative to the braced monopods on Trajan's Column. Upon conducting a wire-frame analysis of it's blown-up image I realized that what I was seeing was an underslung wood-framer with an exceedingly long case (just like Cremona) and a new winch mechanism with two ratcheted handles rather than Vitruvius' drums. It has longer handles gain better leverage and is winched with the case laid down on top of the fixed backstay. The backstay itself now connects closer to the top of the columna No hinged prop or chelonium is needed or evidenced.
@70-88 AD Roman engineers improving on Heron's idea upscale the in-swinger design to where it becomes practical. A stand-mounted version can use a winch and circular ratchet to harness the increased power. Because they are in-swingers, the new weapons have significantly less of their case length aft of the universal/swivel joint. Thus, the backstay can be shorter and steeper making the weapon easier to shoot at high angles for long range fire. The new design perfected enough to be taken on campaign against the Dacians, where a number are lost to the enemy.
@98 AD The Tomb of Vedinnius Moderatus features a relief of a wood-framer very similar to the Xanten find. It is oversprung, has a narrow single arched aperture, and no stand is included. What could be a transverse belly rest (crescent shaped fixture) similar to the gastraphetes and Heron's cheiroballista is seen behind the drawn arms and bowstring ends of the machine. It is the last evidence of a wooden-framed engine until the much different Hatra in-swinger some 200 years later. Two other significant finds around this date are the Bath washer and the Elginhaugh washers and ratchet. Since they are even smaller than Xanten they could be taken as evidence that Heron's cheiroballista had been "up-gunned" just enough to begin replacing the venerable scorpio minors in the hand-held role as well. Some have suggested that these smaller washers were from training or demonstration models of the larger engines. If all small washer machines (say under 45 mm) of the Roman era were "training" machines, their survival rate compared to actual full-scale combat weapons appears vastly out of proportion.
101 AD Trajan's Forces attack the Dacians and recapture the weapons lost over a decade before, using ferroballistae mounted on a modified version of the Cupid Gem base. (the lower portion of the monopod has been eliminated so that the weapon can be used directly from a standard mule cart making it a carroballista). The versatile new design is also capable of being fired from parapets and emplaced on log cribbing in hasty defensive works.
197 AD The Column of Marcus Aurelius features what appears to be the "lazy Rho" shaped base of a carroballista in transport like the one in Scene LXVI of Trajan's Column. The one noticeable difference is that the rear corner of the cart appears to be cut off at an angle possibly to allow for greater arc of fire when the weapon is lowered in to the bed of the cart for firing.
Well, there's my current version of things, laid bare for the vultures to pick apart. It is merely my opinion and I invite others to tie the artifacts, texts, and iconography together as they wish using only logic, reason, and as few thready assumptions as needed. Duct tape and large hunks of metal that haven't been dug up in either text or earth are out of bounds. They will be taken away and you won't get them back until the bell rings :lol:
Derek,
I agree with you that iron-framers must certainly have pre-dated their appearance on Trajan's Column. There are two major factors which support this assumption. The first is plain old military logic. It would be folly for a Commander to take a new and untried weapons system on campaign without traditional sytems to fall back on. Unlike the rash Domitian, Trajan was described as militarily astute, so the absence of tried-and-true wood-framers suggests that ferroballistae were sufficiently assimilated and/or provided such superior performance that wood-framers were not needed. The second and more direct source is Cassius Dio. In his description of a battle near the end of Trajan's First Dacian campaign he writes..."Trajan seized some fortified mountains and on them found the arms and the captured engines, as well as the standard which had been taken in the time of Fuscus." Dio p377
Since the engines shown in posession of the Dacians on the column are iron-framers, that strongly supports the existence of ferroballistae in regular field use as far back as 87-88 AD. Let's see if we can come up with a scenario/timeline, supported by the evidence, that can explain the disappearance of the wooden dinosaurs.
@25 AD Vitruvius writes his difinitive text on catapults. The salient features this eras weapons are;
Circular ratchets and drum type winches which have replaced the earlier linear ratchets and turnstiles.
A progressive trend toward shorter side stanchions for a given washer diameter (ie.underspringing compared to his formulaic ideal) as evidenced by the Ampurias, and Caminreal frames.
A tripod-type base with a separate backstay that has a hinged prop and socket (chelonium) to keep the case at waist level while one is winding the winch.
@50 AD Xanten The frame of a small wooden engine is found. It is small enough that it was likely a hand-held scorpio minor. It's most interesting features are;
A narrow single-arched (not palladian-shaped like Caminreal and Cremona) aperture, and a frame that it appears taller/narrower (oversprung) compared to Vitruvius' ideal ratio. This implies shorted arms and a correspondingly shorter draw length which would be useful on a hand-held weapon. On a stand mounted weapon draw length is not as much of a factor.
60-70? AD Heron of Alexandria The real guy, Edison of his era, and most likely candidate to invent something this novel. Writes about a new way of building a hand-held ballista using metal "field frames" spaced widely apart so that the arms can now swing inwards past each other. He doesn't bother to include instructions for building a winch or stand because as a hand-held, manually-spanned weapon, it doesn't need them. It's a cool idea, but underpowered for military use and won't yet supplant traditional weapons like Xanten.
69 AD Cremona Washers and a battleplate for a weapon are found (or should I say lost). The aperture is palladian-shaped and using the battleplate as a guide it is even further undersprung than Ampurias or Caminreal. By Vitruvian standards such an engine would need even longer arms and a longer case to compensate. Curiously, the aperture is offset upwards in the frame. This implies that the case and canalis funduswere similarly offset causing the string to ride directly on the "slider" above the plane of the arms. This is not really a problem since it is similar to the earlier gastraphetes and later crossbows. Moving the frame down (let's call it underslung to stick with the theme) makes it easier to aim over the hole carrier.(just for those "field of view" lovers out there :wink: ). The Cupid Gem is of indeterminate age, but I choose to place it here with Cremona or slightly before, but certainly sometime after Vitruvius. The initial reason for that was that, like Alan Wilkikns, I saw its "Itallic A" shaped base as a close relative to the braced monopods on Trajan's Column. Upon conducting a wire-frame analysis of it's blown-up image I realized that what I was seeing was an underslung wood-framer with an exceedingly long case (just like Cremona) and a new winch mechanism with two ratcheted handles rather than Vitruvius' drums. It has longer handles gain better leverage and is winched with the case laid down on top of the fixed backstay. The backstay itself now connects closer to the top of the columna No hinged prop or chelonium is needed or evidenced.
@70-88 AD Roman engineers improving on Heron's idea upscale the in-swinger design to where it becomes practical. A stand-mounted version can use a winch and circular ratchet to harness the increased power. Because they are in-swingers, the new weapons have significantly less of their case length aft of the universal/swivel joint. Thus, the backstay can be shorter and steeper making the weapon easier to shoot at high angles for long range fire. The new design perfected enough to be taken on campaign against the Dacians, where a number are lost to the enemy.
@98 AD The Tomb of Vedinnius Moderatus features a relief of a wood-framer very similar to the Xanten find. It is oversprung, has a narrow single arched aperture, and no stand is included. What could be a transverse belly rest (crescent shaped fixture) similar to the gastraphetes and Heron's cheiroballista is seen behind the drawn arms and bowstring ends of the machine. It is the last evidence of a wooden-framed engine until the much different Hatra in-swinger some 200 years later. Two other significant finds around this date are the Bath washer and the Elginhaugh washers and ratchet. Since they are even smaller than Xanten they could be taken as evidence that Heron's cheiroballista had been "up-gunned" just enough to begin replacing the venerable scorpio minors in the hand-held role as well. Some have suggested that these smaller washers were from training or demonstration models of the larger engines. If all small washer machines (say under 45 mm) of the Roman era were "training" machines, their survival rate compared to actual full-scale combat weapons appears vastly out of proportion.
101 AD Trajan's Forces attack the Dacians and recapture the weapons lost over a decade before, using ferroballistae mounted on a modified version of the Cupid Gem base. (the lower portion of the monopod has been eliminated so that the weapon can be used directly from a standard mule cart making it a carroballista). The versatile new design is also capable of being fired from parapets and emplaced on log cribbing in hasty defensive works.
197 AD The Column of Marcus Aurelius features what appears to be the "lazy Rho" shaped base of a carroballista in transport like the one in Scene LXVI of Trajan's Column. The one noticeable difference is that the rear corner of the cart appears to be cut off at an angle possibly to allow for greater arc of fire when the weapon is lowered in to the bed of the cart for firing.
Well, there's my current version of things, laid bare for the vultures to pick apart. It is merely my opinion and I invite others to tie the artifacts, texts, and iconography together as they wish using only logic, reason, and as few thready assumptions as needed. Duct tape and large hunks of metal that haven't been dug up in either text or earth are out of bounds. They will be taken away and you won't get them back until the bell rings :lol:
P. Clodius Secundus (Randi Richert), Legio III Cyrenaica
"Caesar\'s Conquerors"
"Caesar\'s Conquerors"
