Xing Yi Quan Xue (The Study of Xing Yi Quan) was written by Sun Lutang in 1915.
This book gives clear instructions not only in the basics of Xing Yi Quan and the important principles for beginners, but also clearly teaches and illustrates the major forms of the style including the Five Elements, Wu Xing Lian Huan Quan, the 12 Animals, Za Shi Chui, as well as the paired practice routines of the Five Elements and An Shen Pao.
Sun Lutang mastered all three internal styles of Chinese Boxing: Taiji Quan, Bagua Quan, and Xing Yi Quan. His teachers included: Guo Yunshen (Xing Yi Quan), Cheng Tinghua (Bagua Quan), and Hao Weichen (Taiji Quan). Later in life he founded his own style of Taiji: Sun style Taiji Quan.
I have also seen 6 Section Brocade, 12 Section Brocade, and a version with 32 exercises (which was originally 64 exercises before it was simplified). These sets are usually either Seated Sets or Standing Sets. This 24 Section Brocade contains both seated and standing exercises.
I feel that there is some Japanese influence on how the exercises are presented. Most notably, the seated exercises use the kneeling position, called Seiza in Japan. Although the exercises might not be presented exactly how they would have been practiced in China long ago, I feel practitioners will still find this information useful and interesting in their research.
I also think this book will be interesting to practitioners of Japanese arts who wish to research body training methods and energy training methods. The author of this book claims that these exercises were used by the Japanese Samurai as their body strengthening and longevity method.
According to the original authors words, after practicing this method for 100 days, it can make the tendons, channels, bones, and muscles of the whole body reach the condition of being solid and strong, the activity of blood circulation increases, and it can make the putrid that is stored inside the body exit completely and all sorts of diseases will not be generated. After practicing for 3 years, your strength will grow by 1000 times. The muscles are strong and solid like iron. No matter where, even using knifes and swords to stab and hack, one can not be hurt.