Jo - The Wooden Staff of Japan
The wooden staff of Japan, or "Jo", is a cylindrical straight stick of unassuming character with a length ranging from about 50" to 56" and a diameter of about 1". It is used alone in kata or paired with other Jo and closely linked historically with the Japanese sword. Staffs are inconspicuous and, owing to their elegance and simplicity, are preferred by some martial artists above all other weapons. An understanding of its uniqueness in Japanese martial art history and an insight into its original character, usage and dimensions is related here by Wayne Muromoto in this exerpt of an excellent article in the Koryu Books online archives.
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In this following passage, note the historical references to sizing and dimensions, which have been italicized.
Muso Gonnosuke and the Shinto Muso-ryu Jo
by Wayne Muromoto
If we can believe the legends--and there are more legends than facts concerning these two martial artists--the only person to beat Miyamoto Musashi in a duel was someone as outlandish and eccentric as he was. And to top it off, he did it with a wooden stick. In so doing, Muso Gonnosuke Katsuyoshi gave birth to a martial arts system that would elevate the humble wooden staff to one of the preeminent weapons of the bugei of Japan. We know very little that can be verified about the actual life of Muso Gonnosuke, and the little that we do know must be tempered with the knowledge that much of what has been written has been colored and embellished by later writers to make for exciting reading. Nishioka Tsuneo, head of the Seiryukai organization, cautions that many of the legends purporting Gonnosuke to be a colorful braggart originated long after his actual lifetime. "We just don't know that much about him," Nishioka says. In any case, records note that Gonnosuke's original family name was Hirano, and that he went by the given name of Gonbei early in his life. He was supposed to be a distant descendant of Kiso Kanja No Taiyu Kakumei, a retainer of the famous general, Kiso Yoshinaka. Gonnosuke studied the Tenshin Shoden Katori Shinto-ryu under Sakurai Ohsumi No Kami Yoshikatsu, then he studied the Kashima Jikishinkage-ryu, learning its secret method called the "ichi no tachi". According to legends, Gonnosuke thereupon engaged in various duels throughout Japan to test his skills, never losing any of them until he met Miyamoto Musashi. To be sure, there were wooden staff arts before Gonnosuke's time. The Tenshin Shoden Katori Shinto-ryu had bojutsu methods using the rokushaku bo (six-foot staff), as did the Sekiguchi-ryu, Bokuden-ryu and Takeuchi-ryu (or, as it is alternatively called, Take-no-uchi-ryu). If we follow the lineage line charted in the Bugei Ryuha Daijiten, then Gonnosuke was a student of a teacher of the Tenshin Shoden Katori Shinto-ryu, which is why his style, the Shinto Muso (or Shindo Muso) -ryu contains the appellation Shinto (Way of the Gods).
The Duel With Musashi and Mount Homan
The first duel with Musashi occurred in Keicho 10 (1605), just five years after the Battle of Sekigahara put an end to most internal civil wars and heralded the start of the two-centuries-long Tokugawa peace. The event was supposed to have taken place in Akashi, Harima province. There are different versions of the first duel. A rather silly but entertaining one is concocted by Yoshikawa Eiji in the novel Miyamoto Musashi. However, the first records of such a duel is found in the Kaijo Monogatari, written in 1629. The gist of its version was subsequently published in the Jodo Kyoshi. The following is a synopsis of that episode: There was a heihosha (martial artist) named Miyamoto Musashi. He engaged in duels from the age of 16 and was in about 60 matches. In the sixth month, in Akashi, Harima province, he met Muso Gonnosuke, who was a six foot tall strapping warrior. Gonnosuke was armed with an odachi (a long sword), a two layer overcoat with sleeves, and a haori with a large hi no maru (rising sun). On his lapels were written: "The best martial artist in the land" (heiho tenka ichi), and "Nihon Kaizan Muso Gonnosuke."...Gonnosuke was surrounded by about six deshi followers who accompanied him on a journey to Kyushu. He boasted to Musashi that no one was his equal. In his travels, he had apparently encountered Musashi's father, Shinmen Munisai, a master of the jutte (truncheon)."I have seen your father's techniques, but I haven't seen yours," he said, goading Musashi. (Shinmen) Miyamoto Genshin Musashi was irritated. He was in the middle of carving a willow branch and replied, "If you saw my father's techniques, I am no different."Gonnosuke pressed the issue, badgering Musashi to show his martial arts off for the benefit of Gonnosuke's students."My heiho is not for display," Musashi snapped. "No matter how you attack me, I'll stop it. That's all there is to my heiho. Do what you will, with any technique."Gonnosuke pulled out a four-shaku (a shaku is roughly equivalent to an English foot) wooden sword from a brocade bag. (To draw a comparison, the usual practice sword is but a little longer than two shaku.) He attacked Musashi without any formalities. Musashi stood up from his crouch. With what seemed to be very little effort, he forced Gonnosuke back across the tatami mat room with his willow branch and, pressing him against a wall, struck him lightly between the eyebrows. Another slightly different version of that first duel appears in the Honcho Bugei Koden. The book was originally compiled in Shotoku 4 (1714). Watatani, in his edited and annotated version of the Honcho Bugei Koden, notes that the Nitenki, a compilation of Musashi's exploits by his followers, places the event in Edo, but this appears to be a later corruption. The earliest record of this duel appeared in the Kaijo Monogatari, but 26 years after Musashi's death, and it places the battle in Akashi. The description of the duel in the Honcho Bugei Koden is more or less the same as in the Kaijo Monogatari, with some minor differences. In this version, Musashi was carving the willow branch into a toy bow used for sideshow games. It was a thin piece of wood only two shaku or so in length. Musashi invited Gonnosuke into a seven and a half mat room. In actuality, it is probable that Musashi beat Gonnosuke by using his special two-swords technique (nito), trapping Gonnosuke's weapon in an x-block, or juji dome, with his long and short swords. Musashi was able to trap an opponent's weapon with the block, forcing the attacker to either give up or retreat and face an immediate counter-attack. Gonnosuke must have been a large, strapping warrior, if he wielded such a large bokken or bo. A wooden sword attributed to Gonnosuke at Chikuwa Shrine is over four shaku, nine sun and two bu (over four feet) long. Gonnosuke's jo, if measured by the width of his outstretched hands held out to his sides, must have been a bit longer than the standard jo used nowadays. Whatever the case may be, Gonnosuke lost the first duel. Mortified, he withdrew to Homangu, part of the Kamado Shinto shrine atop Mount Homan, in Chikuzen province, (present-day Dazaifu, Fukuoka Prefecture) Kyushu. For 37 days he meditated and performed rites of austerity. On the last night night, while praying in front of an altar, he collapsed and had a divine vision. In one version, a heavenly child appeared and said, "Holding a round log, know the suigetsu (an attack point on the body)." The cryptic vision compelled Gonnosuke to whittle a short staff about four shaku, two sun and one bu in length (128 cm.). This was longer than the standard tachi long sword of that period, which was three shaku, two sun and one bu, but shorter than the long rokushaku bo. By taking advantage of the short staff's ability to shift rapidly in the hands of a skilled artist, Gonnosuke was able to beat Musashi in a second duel. It is unclear how Gonnosuke did that, but the use of the jo in present-day Shinto Muso-ryu practice might give us a hint. If a jo is blocked by a juji-dome, it is an easy matter to quickly flip the jo out of the block and in the same motion strike a kyusho (weak point) on the swordsman's body. Gonnosuke also created a system of five secret methods (hiden gyo-i) that incorporated all the techniques of his new jo style. Gonnosuke managed to defeat Musashi without causing him great harm. Gonnosuke became martial arts instructor to the Kuroda clan, located in northern Kyushu. Muso Gonnosuke, profoundly changed by his encounter with Musashi and by the divine vision atop Mount Homan, had created a preeminent staff art, the Shinto (or Shindo) Muso-ryu jojutsu. The Heavenly Way of Muso's staff...
It is interesting to note that by these accounts, Muso's "post enlightenment" Jo has a specific length and seems not to be tailored (as were his earlier huge wooden swords) to the fact that he was a large man. The Jo of Muso Gonnosuke and that of the school that bears his name, the Shinto Muso Ryu, is 4 shaku, two sun and one bu - or about 50 1/4" in length with a diameter of 8 bu - or 15/16". Kingfisher offers this size as a standard option. Many martial artists however, use Jo tailored to their physical height and certain dojo and organizations adopt other size guidelines as shown below.
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