〈蹶張弩說〉 An Article about Juezhang CrossbowP.S: Juezhang Crossbow comes out since Spring and Autumn Period in China's history (770 BC - 476 BC)It's a type of Crossbow that uses foot to trigger and fire, its length is about 1.6 meter, arm is about 0.7 meter )After search, I found some interesting photos from a cartoon, :-)

弩者，怒也。(Crossbow is a weaspon that fires from the man's angry. P.S: The pronunciation of "Crossbow" is similar to "Angry" in chinese)一定之力，母有增加，如常用弩力有一百五、六十觔者，用箭不過重二錢。A common crowwbow has a 150~160 Jin draw( Jin is a weight unit in Ming Dynasty, it's about 0.59kg ), it uses arrows with 2 qian(Qian is a weight unit, Ming Dynasty, 1 Qian≈5gram )P.S: Still not sure about the weight unit...sorry, it's too hard to find more accurate information from the internet

在五十步之間，發則準而有力。In 500 steps distance ( about 250 meters, I think? ), the cross bow can fire arrows fast, accurate and penetrate.苟貪射遠，難必命中，且力弱不能洞堅。古云：「强弩之末 ，不能穿魯縞。」是也。It can not fire long distance targets effectively as there's an old saying, " a spent force can not enter Lu silk "(P.S: Lu is a small kingdom that's famous for making silk in the Spring and Autumn Period)

弓者，窮也。弓與人力，各得窮盡也。如弓力四十觔，人皆可用，能發五錢重箭，何也？箭長二尺三寸，搭上弓弦，弦去弓背五寸，除去五寸，仍餘一尺八寸 。Bow is different with Crossbow. Everyone can fire a bow with 40 Jin fraw and 5 Qian arrow.A bow's length is 3 Chi 3 cun ( " 3 Chi 3 cun" is about 110 cm )An arrow's length is 2 Chi 3 cun ( about 76.65 cm )The brace height is 5 cun ( about 16.66 cm )扯滿至彀，弓來合深力盡，又加射者撒放之巧力，故箭發百步，仍能殺敵。With a full draw and bowman's technical, the arrow can be fired more accurate than a crossbow.

其弩上弦 只餘五寸至機，箭發只有五寸之力。弩擔已不能如弓來之合深，人又不能施其巧力，故弩力雖大，用箭反輕，不能致遠；弓力雖小，用箭反重，百步猶有餘力。Due to the mechanism difference, a cross bow can not fire longer than a bow while its draw weight is heavier

是弩之怒力不能及弓之巧力也 。然而世之習弓矢者，比比皆是。計百千中，未必得一精巧者，其技至難也。故阮子曰：「世多善弩，而拙於弓。」弓無法準，故任巧由意。弩有法準，故易有善。A bow needs the shooter's technical and that's why it can fire longer than a crossbow.

而況余今所制蹶張之弩 ，中力即能輓；下愚亦可習。如後上法、射法，朝學可以暮成。遠雖小遜於弓，而凖過之。雨露無妨，費亦倍省。上弦搭箭，十步之内，猶能殺人。若弓 ，似又不及矣！

However, a crossbow's skills can be easily learned. It can kill a man within 10 steps distance easily while a bow can not

〈蹶張弩銘〉

蹶濟其擘，弩生於弓，其所自乃子之孝，其所復則臣之忠。

又〈戒射禽銘〉

古制弓弩，以征無道政，為除其害生者。後世藉此，反以傷生。

殊失制者之仁。今之弩凖於弓。夫得奇巧，猶且害生不淺，況蹶張制善機妙，習又易精。倘以射生 ，十必無一存者。余懼，故作銘以戒之。銘曰：以禦暴發爾機，以不為暴自（息）爾機。慎勿傷生兮，機心非。

The above words is a poem that wrtie by the author, he wants to tell readers that a crossbow is manufacturedfor self-defense and Against tyranny, not to harm folks.

Juezhang Crossbow