Training in Internal Iron Palm does not involve hardening of the hands.
Hsing-i training with Axe Hand is the best tool.
Because his iron palm was so good, he was nicknamed "Iron Palm Kuo Yu Chang". His hands were soft as cotton which was not unusual. But when he used his hands, it smashed rocks into many pieces and could bend raw iron. Many Kwangchou people have seen him take ten tiles, one on top of another, strike the first tile, and the tiles between the top and the bottom tiles broke into pieces, but both the top and bottom tiles remained intact.
First Demonstration of Kuo Yu Chang in 1925, Kuo Yu Chang's iron palm abilities were witnessed by a certain Hwang Hsien Sheng. To summarize the story, a Russian circus had posted an open challenge to anyone who would dare take three kicks from one of their horses. Anyone who survived would receive $1000 in gold, a huge sum of money at that time. Kuo Yu Chang accepted the challenge under one condition; instead of money, Kuo asked to strike the horse with one slap of his palm. The Russian owners of the circus accepted his conditions. In front of a huge crowd, the horse raised his hind leg and kicked Kuo in the chest. The crowd was silent in disbeleif. Kuo then gathered his strength and when the horse kicked Kuo a second time, the crowd roared. When the horse kicked Kuo a third time, the crowd gave Kuo a huge ovation. Kuo then rested for more than half an hour. When he returned, he struck the horse in the rear, and the horse fell dead. Again, the crowd cheered at this incredible feat.
The famed Eagle Claw master, Lau Fat Meng, witnessed the postmortem on the horse. He observed that there was no external wound on the horse but that inside there was a large bruise on the horse's back and some of the horse's internal organs had been badly damaged
In 1931, a strong man from Russia came to Kwangchou at west Mellon Garden (now located at the People's Southern Road Kwangchou's Daily News Neighborhood), to demonstrate strength feats. We accompanied Kuo Yu Chang to see the strong man. When he came on stage, he pulled along a wild horse which no one could get near. If anyone could withstand a kick from the horse and not get killed, he would receive $200.00. Then someone in the audience shouted, "Russian, don't be so smug. Iron Palm Kuo is here to cut the strong man down to size and to show how proud Chinese are." Kuo Yu Chang went up on the stage. The strong man observed that Kuo Yu Chang appeared to be an uncommon man. Since the Russian did not know Kuo Yu Chang's background, he demanded Kuo Yu Chang have an examination by a medical doctor to insure that he was a normal human. Finally Kuo Yu Chang went to confront the wild horse. He got near the horse and using his palm lightly slapped it on the back. Immediately the horse did not move. On the second day, the horse did not eat and died. The doctor autopsied the horse and found severe internal injuries. The Russian quietly packed and left. This event of the 1930's is still much talked about among the old Kwangchou people today.
The physics term entrainment is one explanation of how internal blows will cause damage by the transmission of negative energy; that can pass through other areas, without damaging and/or moving them. This is how Kuo Yu Chang (Gu Ruzhang) can break a brick in the middle of a stack, without harming the rest.
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