Minamoto Ippō katana with rare gold inlaid saidan mei, Kin Zogan – Nezu Saburōbei no Jō Mitsumasa cut [with this blade] on the
sixth day of the twelfth month of Genroku three (1700), year
of the horse, through three bodies.
Mounted in Shirasaya and also Kohirae with Sukashi iron Crane motif Tsuba. Fuchi Kashira are Shakudo with Gold Mons, Menuki are also Shakudo with Cranes in Gold
Mei (銘文) ‒ Signature: Gōshū-jūnin Sasaki Nyūdō Minamoto Ippō
(江州住人佐々木入道源一峯) ‒ “Layman Sasaki Minamoto
Ippō, resident of Ōmi province”
Kinzōgan-mei on reverse: Genroku san kanoe-umadoshi jūnigatsu muika ‒ Mitsu-dō
otoshi Nezu Saburōbei no Jō Mitsumasa + kaō (元禄三庚午
“Nezu Saburōbei no Jō Mitsumasa cut [with this blade] on the
sixth day of the twelfth month of Genroku three (1700), year
of the horse, through three bodies.”
Tsukurikomi (造り込み) ‒ Shape: shinogi-zukuri, iori-mune
Kitae (鍛) ‒ Forging: dense itame, tending towards ko-itame
Hamon (刃紋) ‒ Hardening: rather wide chū-suguha
Bōshi (鋩子) ‒ Hardening in tip: sugu with a rather pointed kaeri
Nakago (中心) ‒ Tang: mekugi-ana (目釘穴) 1, yasurime (鑢): ō-sujikai
Made around Tenna (天和, 1681-1684)
IPPŌ (一法), Jōō (承応, 1652-1655), Yamashiro – “Jōshū Fujiwara Hokkyō Ippō” (城州藤原法橋一法), “Heki Yamashiro no Daijō Minamoto Ippō” (日置山城大掾源一法), “Heki Yamashiro no Kami Minamoto Ippō” (日置山城守源一法), real name Heki Ichinojō (日置一之丞), he also bore the first name Saburōzaemon (三郎左衛門) and belonged to the school of Ishidō Korekazu (石堂是一), he worked in Kyōto but it is said that he also made some blades in Edo, hiro-suguha with saka-ashi IPPŌ (一法), Genroku (元禄, 1688-1704), Musashi – “Tsushima no Kami Tachibana Ippō” (対馬守橘一法), “Tsushima Nyūdō Tachibana Ippō” (対馬入道橘一法), according to a theory this was the nyūdō-gō of the Ishidō smith Tsushima no Kami Tsunemitsu (常光), other see him as a separate smith, there exists a date signature of the eleventh year of Genroku (1698) with the age of 73 which would support the theory that this was a pseudonym of Tsunemitsu that he used in his later years, other sources list Ippō also with another gō, Chikyū (知休), which was in turn used by Tsunemitsu too IPPŌ (一峯), 1st gen., Keian (慶安, 1648-1652), Ōmi – “Ippō” (一峯), lived in Sasaki (佐々木) in Ōmi province, he belonged to the Ōmi-branch of the Ishidō school (石堂), suguha, gunome-midare, chōji-midare, suguha mixed with midare, notare-midare, also with nie and sunagashi, it is said that he also used nanban-tetsu, wazamono, jō-saku IPPŌ (一峯), 2nd gen., Genroku (元禄, 1688-1704), Ōmi/Edo – “Gōshū-jūnin Sasaki Zenshirō Minamoto Ippō” (江州住人佐々木善四郎源一峯), “Gōshū-jūnin Sasaki Nyōdō Minamoto Ippō” (江州住人佐々木入道源一峯), real name Sasaki Zenshirō (佐々木善四郎), he moved later to Edo and settled there in the Akasaka (赤坂) district, chōji- midare, gunome-midare, suguha mixed with midare, notare-midare, he also hardened a chōji-gunome-midare in the style of the Ichimonji school, it is said that he also used nanban-tetsu, wazamono, jō-saku
As mentioned, we can get a pretty good overview of the tameshigiri terms in use in the early Edo period by looking at the large number of extant swords with cutting test inscriptions from that time, but the very first drawing of a human body with all the cuts and names drawn in dates to the Genroku era (1688-1704) and is found in a record of the curriculum of the Nezu-ryū of tameshigiri, titled Tōryū-shikake-mokuroku (当流仕掛目録). The Nezu-ryū is thought to go back to Nezu Saburō Mitsumasa (根津三郎兵衛 光政) who was a student of the second Yamano-generation Kanjūrō Hisahide. This drawing shows, from top to bottom, and horizontally downover the body, the following 16 cuts (the notation follows the original, the terms in quotation marks are the literal translations):
1. suritsuke (スリ付, “rubbing”)
2. taitai (太々, “very thick”)
3. kenashi (毛ナシ, “no hair”)
4. ō-kenashi (大毛ナシ, “large no hair [cut]”) 5. wakige (脇毛, “armpit hair”)
6. hitowaki (一脇, “one armpit”)
7. ichi no dō (一の胴, “first torso [cut]”)
8. ichi-ni no ai (一二の間, “between first and second [torso cut]”) 9. ni no dō (二の胴, “second torso [cut]”)
10. ni-san no ai (二三の間, “between second and third [torso cut]”) 11. san no dō (三の胴, “third torso [cut]”)
12. hachimai-me (八枚目, “chairman/promoter”)
13. hosogoshi (細腰, “slender hips”)
14. kurumasaki (車先, “tip of the wheel”)
15. ai no kuruma (間の車, “middle wheel”)
16. moro-guruma (両車・諸車, “both wheels”)
The Yamada family redefined the Nezu-ryū curriculum of cuts after having the monopoly for the bakufu ́s O-tameshi-goyō post, i.e. from the end of the Kyōhō era onwards (享保, 1716-1736). So, if we follow this approach that the Yamada redefined the Nezu-ryū cuts, it must have taken place somewhere between the end of Kyōhō era and Sudō ́s drawing and thus we can narrow down the process to about fifty years. But it is on the other hand also possible that the 16 Nezu-ryū torso cuts had already been simplified earlier, i.e. before Genroku, and that only this school of tameshigiri stuck to this high number of torso cuts. In other words, and following this approach, the Yamada family had later simply changed the names of the already redefined and reduced 10 torso cuts.
Haba hiroku shinogi no hikiku sori no ari katana wa kirete oto no kaki mono, deki saete shinogi no takaki tachi wa tada kirete mo oto no araki mono nari. (はばひろ くしのぎのひきくそりの有刀は切れておとのなきもの・出来さへ てしのぎの高き太刀はただ切れてもおとのあらき物也).
Mitsumasa also wrote on the feedback a blade gives the sword tester during a cut by referring to the interplay of steel (jigane, 地鉄) and cutting ability. When cutting with a Masamune (正宗) and a Sadamune (貞宗), Mitsumasa felt that the Masamune’s steel is relatively “soft” (shirui, シルイ) and that of the Sadamune relatively “hard” (katai, カタイ). Next he wrote that the very densely forged, almost mirror-like jigane of a shintō blade is “tenacious” (shibutoi, シブトイ) and provides in principle a “medium cutting ability.” Mitsumasa further said that Seki or Yamato swords which are made with the strong mizu-ore (三ツオレ) forging technique are especially good cutters. The Shintō-bengi (新刀弁疑, “Almanac of New Swords”), published in five volumes in the sixth year of An ́ei (安永, 1777) by Kamata Natae (鎌田魚妙, 1727-1797), quotes the term mizu-ore with the characters (水折れ). It explains that with this forging technique the steel, or certain parts of the steel, are heated, thrown into water, and then broken into pieces before been further processed. Another jigane-related term that appears in Mitsumasa ́s records is Uzuha (ウツハ). Uzuha is an older, dialect form for Izuha (出羽), a town in Iwami province (present-day Shimano Prefecture) which was a centre for steel production. The Uzuha steel Mitsumasa refers to is basically a “large-scale” mizu-ore as they threw red-hot tamahagane pieces into a pond to cool them down faster. Forging the somewhat rough Uzuha steel well, says Mitsumasa, makes great cutters.
A blade forged with zuku-oroshi (ヅクオロシ・銑卸し), he says, cuts well but is not a superior cutter as it has a somewhat more brittle cutting- edge and is prone to chipping. Zuku-oroshi is pig iron with a high carbon content which is usually only added to a certain extent to the tamahagane when forging a sword. And nanban-tetsu is said to be hard when forging but becomes softer towards the end of the forging process. Thus, such blades were described as cutting nicely the very first time but were not able to maintain a lasting sharp cutting-edge. The Yamada family too recorded their experience with the different kinds of jigane of the swords they tested. The Tōryū-ichiryū tameshimono-kiwame hiden no maki subdivides the hardness and toughness of a blade ́s steel into ten categories, though the descriptions of these categories are ambiguous and are no longer comprehensible.
Above information about Mitsumasa is from the Markus Sesko Tameshigiri book.