Wubei Zhi (Vol. 34)

When released, it is accurate and powerful. However, if one greedily seeks only to shoot at great distances, it is difficult to guarantee a hit; furthermore, the force will be so weak that it cannot penetrate hard targets. As the ancients said: "The force of a powerful crossbow at the end of its flight cannot even pierce thin silk from the state of Lu." Original: Qiangnu zhi mo, bu neng chuan Lu gao (強弩之末不能穿魯縞). This famous idiom from the Records of the Grand Historian describes a force that has exhausted its momentum and become harmless. This is exactly the point.

The word bow Original: Gong (弓). means "exhaustion" or "reaching the limit" Original: Qiong (窮). Like the previous page's explanation of "crossbow" as "fury," this is a play on words suggesting that the weapon represents the absolute limit of tension and energy.. This is because the strength of the bow and the strength of the man are both pushed to their absolute limits.

For example, a bow with a pull of forty catties The text reads xun (勛), likely a transcription error for jin (斤/catties), or a specific local measure of tension. A 40-catty bow is a standard weight for a trained soldier. can be used by most men. Why is it that it can fire an arrow weighing five mace? Original: Qian (錢). A unit of weight; five qian is approximately 19 grams. The arrow is two feet and three inches long. When it is notched upon the bowstring Original: Gongxian (弓弦)., the string is five inches away from the back of the bow. If you subtract those five inches, there remains one foot and eight inches of travel when the string is pulled to the full draw Original: Cheman zhi gou (扯滿至彀). Gou refers specifically to the maximum arc of a drawn bow..

Because the bow's return stroke is deep and its energy is fully spent, and because the archer adds the skill of the release Original: Safang zhi qiaoli (撒放之巧力). This refers to the "snap" or "follow-through" a skilled archer provides, which a mechanical trigger cannot replicate., the arrow can still kill an enemy at a hundred paces. In contrast, when a crossbow is strung, there are only five inches of distance remaining until the string reaches the trigger mechanism. Thus, when the arrow is released, it only benefits from five inches of power. The crossbow arms Original: Nudan (弩擔). Literally the "shoulders" or the stave of the crossbow. cannot "close" as deeply as the bow does, and the operator cannot apply the "skillful force" of a manual release. Therefore, even though the static power of a crossbow may be great, the arrow it uses is actually lighter, and it cannot reach as far as the power of a bow...