Excerpt from <span class="chinese-post-title">十三勢行功要解</span> the Important Explanations for the Accomplishment of the Thirteen Postures by <span class="chinese-post-title">武禹襄</span> Wǔ Yǔxiāng

行氣如九曲珠,無微不到.運勁如百鍊鋼,無堅不摧.

"Circulate Qi as if threading through nine curved pearls, not even the tiniest won’t be reached. Apply power (Jin) as if it was steel refined a hundred times, there is no stronghold one cannot overcome."

By Wǔ Yǔxiāng (武禹襄), based on the translation by Yang Jwing Ming (楊俊敏) presented in the book Tai Chi Secrets of the Wu & Li Styles (太極拳武李氏先哲秘要) and various translations on the internet.