Chinese multiprod crossbow

Credited with the invention of crossbow, the Chinese were keen on tinkering with their crossbow and coming out with ever more efficient and powerful designs. Apart from repeating crossbow, which was invented as early as 4th century BC, Chinese also created another unique crossbow design — the multiprod crossbow, sometimes also known as multiple bow arcuballista. The weapon mounts multiple prods to extend the draw length (and powerstroke) of the crossbow, thus getting more power out of the same draw weight. It is also more efficient and portable than a single prod crossbow of equal power.

There were several variants of multiprod crossbow in use during Tang and Song period, which will be detailed below:


Shuang Gong Chuan Nu (雙弓床弩, lit. 'Double-prod bed crossbow')
Also known as Liang Gong Nu (兩弓弩, lit. 'Two prod crossbow') during Tang period, this crossbow has two prods mounted facing opposite directions of each other. It is spanned by a simple windlass.

Note that the "bed" in its name refers to lathe bed (as the crossbow frame looks similar to a lathe) instead of sleeping bed.


Da He Chan Nu (大合蟬弩, lit. 'Great combined cicada crossbow')
Drawing of a Da He Chan Nu, from 'Wu Bei Zhi (《武備志》)'. Note that while this drawing depicts two double-prod crossbows mounted on an elongated frame, written description mentions no such configuration.
So named because the prod configuration gives off the impression of a pair of mating cicadas, He Chan Nu (合蟬弩, lit. 'Combined cicada crossbow') is simply another name of double-prod crossbow. Da He Chan Nu refers to a large version of double-prod crossbow that requires seven to ten men to span. It has a range of about one hundred and fifty paces.

*NOTE: A Song Dynasty pace can be roughly equated to 1.536 metres or 1.68 yards.


Xiao He Chan Nu (小合蟬弩, lit. 'Small combined cicada crossbow')
Drawing of a Xiao He Chan Nu, from 'Wu Bei Zhi (《武備志》)'.
Xiao He Chan Nu is simply a smaller version of He Chan Nu. It requires five to seven men to span, and has a range of about one hundred and forty paces.



San Gong Chuang Nu (三弓床弩, lit. 'Three prod bed crossbow')
Also known as Ba Niu Nu (八牛弩, lit. 'Eight ox crossbow'), this crossbow mounts three prods, two prod facing forward and one prod facing backward. It is significantly more powerful than its double-prod counterpart.

It is speculated that Kaman-i Gav (lit. 'Ox bow') used by the Mongols during the siege of the Hashashin castle of Maymum Diz in 1256 was in fact a San Gong Chuang Nu.


San Gong Nu (三弓弩, lit. 'Three prod crossbow')
Drawing of a San Gong Nu, from 'Wu Bei Zhi (《武備志》)'.
San Gong Nu is the ubiquitous Chinese triple-prod siege crossbow. Extremely powerful, it requires seventy to more than one hundred men to span, and has a range of three hundred paces (although its maximum range may well exceeds one thousand paces).


Ci San Gong Nu (次三弓弩, lit. 'Lesser three prod crossbow')
Drawing of a Ci San Gong Nu, from 'Wu Bei Zhi (《武備志》)'.
Ci San Gong Nu is a smaller version of San Gong Nu. It requires only thirty to seventy men to span, and has a range of about two hundred paces. While less powerful than its larger counterpart, Ci San Gong Nu is still extremely powerful for its size. Its portability makes it uniquely suited for siege situation, where it can be used to shoot specialised arrows that can be used by other troops as scaling ladder.



Dou Zi Nu (㪷子弩, lit. 'Bucket crossbow')
Dou Zi Nu is a modified multiprod crossbow that mounts an iron bucket to its string. Instead of shooting a single large crossbow bolt, Dou Zi Nu shoots dozens of normal-sized arrows from its iron bucket over a large area.

Presumably, all multiprod crossbows can be converted into Dou Zi Nu.


Dou Zi Nu (㪷子弩)
Drawing of a Dou Zi Nu, from 'Wu Bei Zhi (《武備志》)'.
Dou Zi Nu requires only four men to span. While weaker than even a Xiao He Chan Nu, it still has a range of about one hundred and fifty paces.


San Gong Dou Zi Nu (三弓㪷子弩)
Drawing of a San Gong Dou Zi Nu, from 'Wu Bei Zhi (《武備志》)'.
San Gong Dou Zi Nu is the triple-prod version of Dou Zi Nu. It has a range of about two hundred paces.



Shou She Nu (手射弩, lit. 'Hand-shot crossbow')
Shou She Nu is the handheld version of Chinese multiprod crossbow. While small enough to be handled by one person, its accompanying frame (with windlass) still requires two or more men to operate, so it is not a man-portable weapon in the strictest sense.

The details of operation of Shou She Nu is unknown. It is possible that the crossbow is attached to the wooden frame for spanning purpose only. Once cocked and loaded, the crossbow is then removed from the frame and shot by hand.


Shou She He Chan Nu (手射合蟬弩, lit. 'Hand-shot combined cicada crossbow')
Shou She He Chan Nu is the handheld version of double-prod crossbow. Unfortunately, no other information is available for this crossbow.


Shou She Nu (手射弩)
Drawing of a Shou She Nu, from 'Wu Bei Zhi (《武備志》)'.
Presumably also called Shou She San Gong Nu (手射三弓弩, lit. 'Hand-shot three prod crossbow'), this is the handheld version of triple-prod crossbow. Despite being a handheld crossbow, it still requires up to twenty men to span, and has a range of about one hundred and fifty paces.


Shou She Dou Zi Nu (手射㪷子弩, lit. 'Hand-shot bucket crossbow')
Shou She Dou Zi Nu is the handheld version of Dou Zi Nu. Described as the smallest of multiprod crossbows, it requires less than five men to span, but still retains a range of around one hundred and twenty paces.



Crossbow bolt
From left to right: Tie Yu Zao Tou Jian, Da Zao Tou Jian, Xiao Zao Tou Jian, Ta Jue Jian, Yi Qiang San Jian Jian, Dou Zi Jian. It should be reminded that these crossbow bolts are NOT properly scaled to each other.
Chinese multiprod crossbow can be loaded with a variety of crossbow bolts, each designed for different purposes.

Zao Tou Jian (鑿頭箭, lit. 'Chisel-headed arrow')
Like its namesake, Zao Tou Jian has a chisel-like arrowhead, presumably designed to inflict wide gaping wounds. The fletching of Zhao Tou Jian can be made of either iron or feathers.

Zao Tou Jian comes in various sizes, the smallest variant can apparently be loaded into the iron bucket of a small Dou Zi Nu.


Ta Jue Jian (踏撅箭, lit. 'Stepping arrow')
Ta Jue Jian is designed to be used as scaling ladder for besieging troops. As such, its has a large barbed arrowhead designed to pierce and lodge firmly into hard surfaces, as well as a thick and sturdy shaft that can withstand the force of impact and the weight of armoured trooper.

With the power of multiprod crossbow behind it, this type of crossbow bolt should be able to punch into stone brick.


Yi Qiang San Jian Jian (一鎗三劒箭, lit. 'One spear three swords arrow')
Yi Qiang San Jian Jian is the largest and most deadly of the multiprod crossbow bolts. Essentially a heavy spear with three iron fletches (the three "swords"), it is only lauched from the largest San Gong Chuang Nu.


Dou Zi Jian (㪷子箭)
Dou Zi Jian is actually not a specific type of arrow, but a catch-all term for all normal-sized arrows that can be loaded into the iron bucket of Dou Zi Nu. It is also known as Han Ya Jian (寒鴉箭, lit. 'Jackdaw arrow').


Black powder incendiary bolt
All of the aforementioned crossbow bolts can be upgraded with incendiary or poison smoke warheads (or both) to further enhance their destructive potentials. A particular nasty version is the incendiary Dou Zi Jian that can set a wide area ablaze.



Just how powerful is the Chinese multiprod crossbow?
Unfortunately, written records are silent on the matter of dimensions and precise draw weights of these siege weapons, so all estimations on the power of multiprod crossbow are merely educated guesses. That being said, all known multprod crossbow variants inevitably come with windlasses that require at least two operators, so they must be quite powerful.

Also, since none of the windlasses look like they can be operated by more than four persons (let alone one hundred) records of "X number of men required to span the crossbow" must therefore refer to the number of men required to span the crossbow without using windlass, perhaps in a manner not too dissimilar to tug-of-war. Therefore even under the most unfavourable assumption that one man can only pull a meagre 12 kilograms/22.5 pounds (in reality a physically fit and well-trained man can pull roughly twice his own weight), a large San Gong Nu spanned by one hundred men would still have a draw weight of roughly 2645 pounds!



Replica

China's CCTV-9 television channel created a full-scale replica of San Gong Chuang Nu for its ancient Chinese weapon documentary series. The replica manages an impressive 61 inches powerstroke, but only has a paltry draw weight of 390 pounds (incredibly underpowered for a weapon of this size). It can only shoot a spear-sized crossbow bolt (size and weight not given, but most likely too heavy for the draw weight) at an abysmal 91.8 fps.

A complete failure, regrettably.




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2 comments:

  1. What do you think was missing from the restoration that made it so weak?

    ReplyDelete
    Replies
    1. Draw weight. The draw weight is way too small for something that big (390 lbs is the draw weight of a medium-sized handheld crossbow). It should be several times stronger.

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