In this new article we are going to tackle several aspects of another interesting physical phenomenon generated by a katana, the tachikaze. Literally meaning "the Sword Wind", it is the peculiar whistling sound a katana makes when a proper cut is made along its relative cutting plane. In a katana with bo-hi (the longitudinal side indent originally created to lighten the blade without compromising its integrity and impact resistance) the tachikaze will be a much stronger sound than in one without; this is due to a complex acoustic and aerodinamic phenomenon that generates small air vortexes or disturbances when the edge of the sword is moving on the correct trajectory, as this interesting article from Scientific American explained in very technical detail. Incidentally, this is also the way in which the sword will move through space and, eventually, through a solid object (our opponent, for example) in the most efficient way, by concentrating all of its force on the smallest point of impact (the edge). To better understand how this is achieved, we have to check the below picture: In the picture you can see how, given any position in space for the katana, exists a circular "cutting plane" originating from its edge and of which the sword itself is the radius. In a correct cut the edge of the sword and the circle originating by the katana as a radius in that particular plane are going in the same direction. This will cause the correct "tachikaze" noise and it will tell the user that that cut would have actually cut its target. However, this also means that if the edge of the sword is offset, even slightly, from the circular cutting plane the katana is moving on during the cut, there will be no tachikaze and the sword would not cut, either properly (imagine entering the opponents body superficially and getting bent and stuck) or at all (bouncing back). This is exemplified, in an exaggerated way, by the next drawing: As you can see, the orientation of the edge must be straight relative to the cutting plane of the sword (represented here still by the dotted lines) for it to be cutting efficiently and produce the tachikaze. This is why, in competitions and in higher level exams, as well as in our everyday practice, a good importance is given to reach the correct tachikaze sound; while this is always secondary to formal or execution/body control mistakes, it's the only true feedback we have that we are properly doing Iaido, cutting our enemy (within or not), as opposed to just emptily and soullessly waving a metal object through air!
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Starting from about the beginning of the 20th Century, most of the highest-level masters of traditional Japanese martial arts understood that for the very survival of their historical knowledge something had to change. Gone were the days of the Samurai and a new era was already there: it was time to change the purpose of their arts from "technical arts" (jutsu) to "ways" (do).
To do that, the message of their arts had to modernize itself, while keeping the core values and truths of their techniques alive; for this reason many of the top Masters of the time started to create federation and commissions, coming from many different schools (ryuha) to try and summarize the best principles into something at the same time new and faithful to the originals. It was like this that Kenjutsu, with its many old schools, was condensed into modern Kendo, or Jujutsu into Judo, Daito-ryu Aikijujutsu into Aikido, and so on. This is true also for Iaido, which originally was named Iaijutsu under many different schools: Muso-Shinden, Eishin, Hoki, Mugai, Toyama, Yagyu-Shinkage and so on. In the 1960s a commission was formed to create a system of Kata, or preordained forms, that could be a common base for all of the schools, a good basic learning method and also a form of meditation in movement with self-improvement aspects. Originally composed of 7 forms, it was later increased to 10 and eventually to 12; it was not meant to include ALL of the schools, but more to include most of their principles and fundamental techniques. Today most iaidoka still learn and practice mostly these 12 forms, integrating with each own's personal progress also the traditional school followed by his teacher. It is very interesting to have a look and analyze the various Seitei forms and see which school was its main origin: 1. Mae: The first and fundamental form was taken from Omori-ryu (which is the common set of seiza forms both present in Muso-Shinden and in Eishin-ryu), and originally called "Shohatto"; 2. Ushiro: The same, from Omori-ryu, called "Atarito"; 3. Ukenagashi: Again from Omori-ryu, called "Ryuto" or "Ukenagashi"; 4. Tsuka-ate: from Eishin-ryu; 5. Kesagiri: from Hoki-ryu; 6. Morote-tsuki: composed from basic movements of several schools; 7. Sampogiri: composed from basic movements of several schools; 8. Ganmen-ate: from Muso-Shinden-ryu, called "Moniri"; 9. Soetetsuki: from Hoki-ryu; 10.Shihogiri: from Hoki-ryu; 11. Sougiri: from Muso-Shinden-ryu, called "Somakuri"; 12. Nukiuchi: from Mugai-ryu, callled "Gyokkou"; It is interesting to notice that somehow the distribution of these "origin" schools within the 12 kata also reflects the overall amount of practictioners actively studying these ryuha: for example by large numbers the most popular is Muso-Shinden-ryu, which is present with 5 forms (3 from Omori-ryu and 2 only of Muso-Shinden-ryu), second Eishin-ryu, with 4 forms, third Hoki-ryu with 3 forms, and the other schools following with 1 form or less. It is also interesting to notice how the "origin" forms and the Seitei version tend to be very different in execution and purpose, even if the sequence is immediately recognizable by looking. So even when practicing Seitei, or "modern" Iaido, we are still in fact honoring a tradition going back for centuries and at the same time learning the most important physical and phylosophical aspects of Iai. In fact, I discovered in years of practicing Japanese Budo that the ancient schools present in also a modern set were kept more "alive" than others who chose to remain independent and tied to the past and that today are executed often as an empty repetition of movements. And this is the most important message: no matter which School or which art you practice, make it "yours", make it "alive" - it's the only way to truly preserve it and pass it to the next generation. You can get more information or join our Iaido courses in Singapore on this page or by writing to our email. Following last week's articles, we are today going on talking about the most fascinanting topic: the real Katana.
While "Katana" is the common and known name in popular culture, in Japan and especially in the Budo (Martial Arts) world, it is referred to as a "Shinken", or a "live sword". This means not only that the sword is sharpened, but also that it was made accordingly to tradition in Japan by a certified artisan. It can be an older blade, even centuries old, or a "shinsakuto", a modern one, but made in the very same way. There is a number of variations in lenghts, weight, sori (curvature), presence or not of the bo-hi (a longitudinal partially hollowed out area meant to reduce the overall weight without sacrificing structural stability), different styles of hamon (the line remaining from the clay when the sword is tempered) and so on. Normally in Iaido we tend to use "shinsakuto" with bo-hi, and not excessively heavy swords; this is mainly to avoid injuring one's joints when practicing, but it is also because the peculiar noise a sword with bo-hi does when cutting provides a certain feedback on the accuracy and precision of the cut. Legally, many countries have different regulations, but most have a difficult time categorizing and ruling a Katana. In Singapore there is not a specific "sword" law, so the decisions to allow import or not is demanded to the Police Force. For this reason, sometimes, depending on the Officer in charge of your case, it might be a smooth or less smooth experience. But in general it is possible to import any Iaito and possibly a Shinken, provided you have a clean record, you pay the import licenses, and you do not carry it out of its bag when going around from your house to the Dojo. Even then, you should not forget in the car, for example, while going to the Disco - in case you get stopped there would be no reason for you to have a weapon in your trunk in the eyes of the local enforcement! But transporting your licensed sword back and forth on training days it's not going to be a problem! As always, consider every Iaito or Shinken always as a live weapon with a high capability to harm you or people around you; an healthy measure of respect for your Katana will safeguard your sould, as well as your skin! |
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