iToken Bijutsu No.549j
Nihon Koto Shi
(History of Koto)
By Dr. Honma Junji
Entering the Japanese Sword Age, it became a custom that swordsmiths signed their smith names on the nakago, but there is no extant work of the Shoso-in Depository that has a smithfs name inscribed on the nakago. There are two swords that have characters on the blade amongst 100 tachi of the depository. These characters are inscriptions that praise the swords, but are not swordsmithfs names. Two treasure swords with kin-zogan are registered in eShutsuzo Chof (a list of swords coming both in and out of the collection). There are notes about the two swords on the list, gJidenh and gHito-kuchi Mei Daisho Sakuh (there is a record on the list that the swords were taken out of the depository on the 26th of December, 759). Though I have not been able to confirm that they are smithfs names or their titles, it is uncertain whether these inscriptions chiselled on the blade or nakago.
According to a clause included in eTaiho-ritsuryof (legal codes) that was issued in 701, swordsmiths were ordered to sign their names on the nakago of their works, therefore, there should have been swords with smithfs names on their nakago in that period. How should we understand the actual fact that there is no extant work with a smithfs name in the sword collection of the Shoso-in Depository? Possibly tachi categorised as kin-gin-denso-tachi that were worn by emperors and court nobles, might not be recognised as weapon, therefore, they were not to be subjected to the code. However, muso-to in dabira style should have smithfs names on the nakago since they are to have been used as weapon. I wonder if the clause of the Taiho-ritsuryo was not practised by swordsmiths and resulted in a mere scrap of paper? Incidentally, the Engi-shiki codes issued later orders to officials in charge of swords supplied to the government, to sign their names on the swords, but this did not apply to smithfs names. Meanwhile, swords for sale in the market were still subjected to the clause of the Taiho-ritsuryo codes.
The workmanship of the swords conserved in the Shoso-in Depository was mentioned as above. Let me repeat the main points. Kiri-ha-zukuri are the most popular type and there are swords in shinogi-zukuri that look like kiri-ha-zukuri at a glance, also many kissaki-moro-ha-zukuri (mostly kiri-ha-zukuri) are seen amongst them. There are also some swords in Kogarasu-zukuri. Shallow sori is recognised in them, their mi-haba is wider than that of the Japanese sword in general, most swords have maru-mune, jigane looks soft, nagare-hada is common and masame-hada is also seen, and hoso-sugu-ha is popular and skilfully tempered. Boshi is sugu or gentle then turns back in ko-maru with short kaeri and is elegantly tempered with tight a nioi-guchi. The jigane is covered with thick ji-nie, sunagashi and hakikake are seen, and the hamon starts with yaki-otoshi.
Japanese sword researchers have agreed on a
theory that there is a connection
between the workmanship of the sword collection of the Shoso-in Depository and the
Japanese sword that was developed in the Heian Period and reached the peak of
sword forging skill. That is to say, old Yamato swords are rightly descended
from the swords of the Shoso-in Depository. There are the Senjuin, Tegai,
Taima, Hosho and Shikkake schools in
Now, I would like to point out differences of the workmanship between old Yamato swords and the swords of the Shoso-in Depository. (1) Tachi by Yamato smiths are in shinogi-zukuri and have sori. (2) Their jigane look powerful and nie is more emphasised in the ji and ha, sunagashi and hakikake are more conspicuous. (3) There is no tsuchi-me and sen-suki finishes on their nakago but taka-no-ha, higaki, kiri-yasuri. It must be noticed that the width of their shinogi-ji is wider than that of smiths who lived in other provinces and were active in the same period. They also made many tanto in kanmuri-otoshi-zukuri. It seems to me that this fact suggests how kiri-ha-zukuri had been developed to shinogi-zukuri and kissaki-moro-ha-zukuri.
I have already mentioned that there are kissaki-moro-ha-zukuri amongst the swords of the Shoso-in Depository similar to so-called Kogarasu-maru-zukuri. As the original Kogarasu-maru has deeper sori and narrower shinogi-ji, this means that the sword was made later than those of the Shoso-in Depository. Thus it is speculated that Kogarasu-maru is one of swords made in the Heian Period but the nioi-guchi and the hataraki of the ji and ha closely resemble those of the swords in the Shoso-in Depository. After all, Kogarasu-maru should be recognised as a very early work, inferring from the workmanship. I will have an opportunity to describe Kogarasu-maru in detail later on.
Muso-to in dabira-style that is speculated to have been made for military use
My theory, that the origin of Yamato swords
comes from the swords of the Shoso-in Depository, is as mentioned above and
justified from the view point of workmanship and geography. There is no doubt
that Yamato smiths had had intimate relationship with temples since the
medieval period and supplied the temples, which had many armed monks, with
swords. Especially, I am sure that swordsmiths who belonged to big temples such
It is very difficult to ascertain if the swords of the Shoso-in Depository were made by Japanese or Chinese and Korean smiths, and it is almost impossible to prove that Yamato smiths of that period made them and that Tegai smiths are their descendants. However, after researching the swords of the Shoso-in Depository, it becomes clear that the workmanship of the swords in the Shoso-in Depository had an influence on the sword forging of Yamato smiths..
Tachi by gYukimasah (Naminohira school) with the date of Heiji 1 (1159)
Amongst Japanese swords, a common
workmanship to the swords of the Shoso-in Depository is seen in not only old
Yamato swords but also old swords of the Naminohira
It is known that Masakuni was the founder
of the Naminohira school and smiths in his direct line use the smith name of eYukiyasuf
for generations. It is said that Masakuni was active in Eien Era (987-995) but
no extant work with his signature has been confirmed. There are, however,
extant works of Yukiyasu that appear to have been made no later than the early
Kamakura Period, also there is a extant work with the signature of Yukimasa who
belongs to the Naminohira school and the date of Heiji 1 (1159). All of the old
swordsmith directories say that Masakuni came from
It is often said that yaki-otoshi is a sign of sai-ha (re-tempered blade) but it is one features of Yukihira Yaki-otoshi that is also seen in the swords of the Shoso-in Depository seems to have been a method of yaki-ire (quenching or tempering) since jokoto times. Therefore we can see it in the hamon of famous Kogarasu-maru, Doji-giri Yasutsuna and O-denta Mitsuyo made in the Heian Period. Also a trace of yaki-otoshi is recognised in the hamon of old Yamashiro and Bizen swords.
As I described before, we recognise that Yamato swords are descended from the swords of the Shoso-in Depository. Also it can be said that common features are seen between the workmanship of Yamato and Yamashiro swords. For instance, niju-ba and sanju-ba seen in the hamon of Mikazuki Munechika are peculiar hataraki to Yamato swords but they are also seen in the hamon of the swords in the Shoso-in Depository. Yamashiro smiths are good at tempering elegant boshi with ko-maru and it was already described that there are many Shoso-in swords that have typical ko-maru-boshi. Thus, it is an undeniable fact deniable fact that Shoso-in swords have an influence on Yamashiro swords but an indirect influence on Yamato swords. It is well known that Osafune Nagamitsu and his students temper a unique boshi with tight nioi-guchi called eSansaku-boshif (gentle notare then turns back in ko-maru) and it is very interesting to find exactly the same boshi amongst Shoso-in swords. Of course, there is no direct relation between Nagamitsu and Shoso-in swords but it is amazing that ancient smiths already had such high level technique to temper hoso-sugu-ha and an elegant boshi. If kara-dachi means a sword made in the Tang (Kara) Dynasty of China, kin-gin-denso-kara-dachi conserved in the Hoku-so storage should correspondent to it. Then it may be speculated that other extant Shoso-in swords of the same workmanship were made in China or by smiths who were descended from Chinese smiths. If the theory is correct, the technique of tempering sugu-ha and ko-maru-boshi had already been accomplished and was then introduced to Japan in the Nara Period and eventually Japanese smiths acquired the technique. Entering the age of the Japanese sword, the tempering technique had been developed locally by Japanese smiths who began to succeed in tempering gorgeous midare-ba in the Kamakura Period. Some old books say that Chinese smiths already tempered midare-ba properly before the Tang Dynasty and I speculate that midare-ba of Shoso-in swords tempered with an immature technique is a trace of the technique developed by Chinese smiths.
2. Heishi-shorin-ken, Shichisei-ken and Suiryu-ken
Apart from the swords of the Shoso-in
Depository, there are only few extant jokoto like Shichishi-to owned by the Isonokami
Shrine in Yamato Province, Heishi-shorin-ken and Shichisei-ken owned by the
Shitenno-ji Temple in Settsu Province and Suiryu-ken owned by the Tokyo
National Museum. I have not mentioned Shichishi-to here since several thesis on
the sword have been presented in the past.
Heishi-shorin-ken and Shichisei-ken inherited by the Shitenno-ji temple
have been conserved in good condition and are of high quality. They also have
interesting histories. A document of the temple says that the two swords were
owned by Prince Shotoku. Heishi-shorin-ken have been very famous since very old
days and a description of the swords is found in eKodan Shof. Also eTaishi Den
Kokon Mokuroku Shof written by Kenshin in Karoku 3 (1228) includes a copy of
the four characters gold-inlaid on Heishi-shorin-ken and there are descriptions
of the sword in eTaishi Tokugyo Kuketsu Shof written by Shungen and eTaishi Den
Gyokurin Shof. Though, eKodan Shof makes a mistake in reading of
Heishi-shorin-ken as eHeishi-kairin-kenf. Entering the Edo Period, Arai
Hakuseki who was a famous scholar retained by the shogunate corrected the
reading in his book called eHoncho Gunki Kof. Taishi Tokugyo Kuketsu Sho says
(Reference photos / from right to left)
Heishi-shorin-ken (Kokuho or National Treasure)
Shichisei-ken (Kokuho or National Treasure)
Speaking of the workmanships of the two swords, they are in kiri-ha-zukuri with gently round maru-mune and have relatively short ha-watari (Heishi-shorin-ken : 65.1 cm, Shichisei-ken : 62.4 cm.), wide kiri-ha, thick kasane, conspicuous uchi-zori (Heishi-shorin-ken) and no sori in the nakago. The jigane of Heishi-shorin-ken is amazingly well-forged and the jihada is dense ko-itame-hada combined with masame then chikei and kinsuji are seen. It is speculated that the jigane was forged and folded a certain number of times, using soft material. This forging method is also seen amongst the swords of the Shoso-in Depository. It became clear that three swords polished by Mr. Ono Kokei recently (kin-gin-denso-kara-dachi of the Hokuso storage, No.1 and No.2 tachi of the Chuso storage) were forged in the same method. Mr. Ono stated his impressions after he polished them that he had the same feeling in polishing them as those of old fine Japanese swords. The jigane of the three swords of the Shoso-in Depository look weak but Mr. Ono had the same feeling in polishing them. Heishi-shorin-ken has fine and well-forged jigane with beautiful colour and thick and snow-white nie. Its jihada bears a resemblance to that of Yamato and Yamashiro swords rather than the swords of the Shoso-in Depository. Though, such refined jigane and jihada is seldom seen amongst Yamato swords. The hamon of Heishi-shorin-ken is hoso-sugu-ha mixed with gentle notare and ko-midare then ko-ashi are seen inside the hamon. There is no yaki-otoshi but it starts with yaki-komi. The hamon consists of thick nioi accompanied by ko-nie in the upper part and tight nioi in the lower part and kinsuji and sunagashi are seen in places. Unfortunately the boshi is missing but it is speculated that it was originally ko-maru-boshi. The jigane of Shichisei-ken has no difference from that of the other ordinary swords of the Shoso-in Depository. Masame-hada is more emphasised in the jihada that mixes ko-itame accompanied by thick ji-nie. The hamon is hoso-sugu-ha, inclined to be deformed and has hazy nioi-guchi accompanied by ko-nie, many sunagashi and yaki-otoshi are seen. The boshi is missing but hakikake are seen there. The manner of the ji and the ha of Shichisei-ken reminds of Bungo no Yukihira.
There are four Chinese characters of gHei
Shi Sho Rinh in kin-zogan on the haki-ura and the name of the sword comes from
these characters. eHeishif means eHinoenef one of the zodiac signs but the
meaning of eShorinf is unknown. There is a description of the characters in eGunki
Kof that Shorin could be the name of the smith who made this sword, but I am
doubtful of this theory. Some one says that the kin-zogan and calligraphy are
beyond the skills of Japanese and appear to be the work of Chinese. Meanwhile, eKuketsu
Shof says that it has been said that Heishi-shorin-ken was made in
Suiryu-ken (Juyo Bunka Zai or Important Cultural Asset)
There are futa-suji-bi on both sides of Shichisei-ken then clouds and seven starts (the Great Bear) are gold-inlaid above them. The name of the sword comes from the seven stars. There is a description of eKinro-ryu-seiun –gataf in the Todaiji Kenbutsu Cho and Shichisei-ken comes under this classification.
The bad condition of their nakago makes it very difficult to confirm the yasuri-me, but I can see the trace of tsuchi-me. The nakago have no mekugi-ana but there are kake-toshi-ana in yahazu-gata shape on the tips of the nakago. The kake-toshi-ana of Heishi-shorin-ken is large and that of Shichisei-ken is small.
Putting the history transmitted by the
temple aside, it is hardly possible to differentiate the oldness between
Heishi-shorin-ken and Shichisei-ken objectively. The same thing can be said to
the swords of the Shoso-in Depository. It is possible to tell minor differences
between their workmanships and it is something like the difference of the
workmanship between five schools of Yamato Provinces. It is a miracle that
Heishi-shorin-ken and Shichisei-ken have been safely conserved the Shitenno-ji
Temple that is located in a place with very public access, differing from the
Shoso-in Depository that has been strictly guarded. The two swords were completely
covered with deep black rust but they were restored perfectly last year when
the incredibly beautiful jihada came in sight at last. The Gyokurin Sho says
that the two swords have had no koshirae since the Muromachi Period at the latest.
It is very interesting to know how the bare swords have been conserved in such
condition for 400 years. Why had the erosion by the rust been so slow? It may be
because of the extremely well-forged jigane or the peculiarity of the material.
The research of this subject should be done by metallurgists including the
swords of the Shoso-in Depository. Also Suiryu-ken owned by the
I have introduced jokoto and explained of
the workmanship of the Japanese sword by now. I believe that the jokoto
conserved in the Shoso-in Depository,
Characters of eHeishi-shorin-kenf