Wubei Zhi (Vol. 34)

...he first reached the same conclusions as I did. He matched the ancient designs, but then incorporated his own ideas to create a new style, providing a comprehensive explanation. Furthermore, by using a large mechanism, he recreated what the ancients called the Waist-draw Crossbow Original: Yaokai Nu (腰開弩). This type of crossbow was braced against the feet while the archer used their back and waist muscles to pull the string, allowing for much higher tension than arm strength alone..

Its power can reach thirty-six jun A jun (鈞) is an ancient unit of weight. At thirty catties per jun, this equals 1,080 catties (roughly 1,440 lbs or 650 kg).. Thirty-six jun is 1,080 catties Original: Jin (斤). A traditional unit of weight. by today's standards. Since the time of Ma Long A general of the Jin Dynasty (266–420 AD) famous for his innovative use of mechanical weapons and mobile formations to defeat tribal uprisings., this art has no longer been transmitted. Now, using this method, a man capable of lifting three hundred catties can master it. I have preserved the general description in the section on equipment, but the specific methods of use and construction are detailed here. I record the original text so that it will not be forgotten.

General Preface to the Foot-strained Crossbow

The word crossbow Original: Nu (弩). means "fury" Original: Nu (怒). In traditional Chinese philology, this is a "paronomastic gloss"—a pun used to explain the essence of a thing. The weapon's mechanical release is compared to a sudden outburst of anger.. Its force is fixed and does not increase Unlike a traditional bow, where the archer can vary the draw strength, a crossbow's tension is determined by its mechanical construction.. For example, a common crossbow with a strength of 150 or 160 catties uses an arrow weighing no more than two mace Original: Qian (錢). A small unit of weight; two qian is approximately 7.5 grams. and is effective at a distance of fifty paces.