nntsuzu/KFTT huggingface dataset:
English: The term Japanese sword has been seen connected to nationalism mainly since the Showa period, and such swords were considered just relics of the previous period where in the Meiji period, saber style swords were adopted for the military until the Manchurian Incident.
Japanese: 日本刀という呼称がナショナリズムと結び付いて語られるようになったのは主に昭和に入ってからの事であり、明治時代には刀など前時代の遺物でしかなく、満州事変の頃までは軍刀としてサーベル様式の刀剣が採用されていた。
English: The manufacturing method of Japanese swords, a highly advanced technique at the time, strove to achieve three highly sought after qualities, 'Not to break, not to bend, and a razor sharp cutting edge.'
Japanese: 「折れず、曲がらず、良く斬れる」の3要素を非常に高い次元で同時に実現させるため日本刀の製法には非常に高度な技術が集約されている。
English: Tatara-buki method; the type of steel used to make a Japanese sword is called Japanese steel or Tamahagane.
Japanese: たたら吹き日本刀の材料となる鋼を和鋼（わこう）もしくは玉鋼（たまはがね）と呼ぶ。
English: Not depending upon iron ore imported from other countries, using black iron sand found on beaches in Japan, achieves fast reduction at low temperature, and creates high-quality steel with few impurities, compared to the modern steelmaking processes (See reference).
Japanese: 諸外国の鉄鉱石を原料とする方法から決別し、砂鉄を用いることで低温で高速還元を実現し、さらには近代的な製鋼法に比べ、不純物が少ない良質の鋼を得ることができる（参考）。
English: This case-hardened piece is called Heshi gane (removed metal), which is broken into small metal pieces using a Tsuchi (hammer).
Japanese: この焼きを入れて硬くした塊はへし金（へしがね）と呼ばれ、鎚で叩いて小さな鉄片に砕く。
English: These metal pieces are stacked on the tip of a forging tool called 'Teko', and wrapped in Japanese paper.
Japanese: これらの鉄片を「てこ」と呼ばれる鍛錬用の道具の先に積み上げて和紙でくるむ。
English: Straw ash is applied, and then coated with clay slurry, then it goes into the furnace (Hodo) to heat until the clay surface melts.
Japanese: 周囲に藁灰を付けさらに粘土汁をかけて火床（ほど）に入れ表面の粘土が溶けるくらい加熱する。
English: If there are not enough iron pieces, more are stacked, heated, hammered with a Kozuchi, and formed into an ingot weighing 1.8kg to 2.0kg.
Japanese: 鉄片が足らなければ更に積み上げ加熱して小槌で叩いて成形し所要の1.8-2.0kg程度の量にする。
English: Other than Tamahagane, pig iron (Sentetsu) which contains a lot of carbon, and pure iron called Hocho tetsu also undergo Tsumi wakashi and Shita-gitae processing mentioned below.
Japanese: 玉鋼以外に炭素量の多い銑鉄と包丁鉄と呼ばれる純鉄も積沸かしと次の下鍛えの作業を行なう。
English: The red-hot block is struck and elongated using a Tsuchi (hammer), and folded back into the middle of its length, which is called a 'folding method of forging' and it is done repeatedly.
Japanese: 赤熱したブロックを鎚（つち）で叩き伸ばしては中央から折り重ねる「折り返し鍛練」を繰り返し行う。
English: In fact, the word 'Muko-zuchi,' describes the method by which Tosho (Yokoza, master) and his disciple (Sente, helper) alternately strike the body of the blade with a Tsuchi, and this has become the root of the word 'Aizuchi wo utsu (chiming in).'
Japanese: ちなみに刀匠（横座）と弟子（先手）が交互に刀身を鎚で叩いていく「向こう槌」が「相槌を打つ」という言葉の語源となった。
English: After finishing Shita-gitae with three types of steel, Tamahagane (literally "jeweled steel"), Sentetsu (pig iron), and Hocho tetsu (literally "kitchen knife steel," pure iron), they are hammered using a Kozuchi (light hammer) again to make metal pieces, selected to produce the proper steel composition, they are stacked and formed like the first Tsumi wakashi.
Japanese: 玉鋼、銑鉄、包丁鉄の3種類の下鍛えが済めば再び小槌で叩いて鉄片にし、それぞれの鋼の配合が適切になるように選んで、1回目の積沸かしと同じく積み上げて溶かし固める。
English: In this step, four kinds of steel having different carbon content, Shingane (center metal), Munegane (back metal), Hanokane (blade metal) and Gawagane (side metal), are made.
Japanese: この段階で含有炭素量が異なる心金（しんがね）、棟金（むねがね）、刃金（はのかね）、側金（がわがね）の4種類の鋼に作り分けられる。
English: Shingane are folded back 7 times, Munegane 9 times, Hanokane 15 times and Gawagane 12 times.
Japanese: 心金で7回、棟金で9回、刃金では15回、側金では12回程度の折り返しが行なわれる。
English: By repeatedly forging after folding back the steel struck and elongated, impurities such as sulfur, excess carbon and non-metal impurities are removed, and a strong and homogeneous steel is created.
Japanese: 叩き延ばした鋼を折り返しながら鍛錬を重ねることで、硫黄などの不純物や余分な炭素、非金属介在物を追い出し、数千層にも及ぶ均質で強靭な鋼へと仕上がっていく。
English: After getting four kinds of steel, Shingane (center metal), Munegane (back metal), Hanokane (blade metal) and Gawagane (side metal) by Shita-gitae (forging), the second Tsumi wakashi (stacked and heated metal) and Age-gitae (finishing forging), three layers of Munegane, Shingane and Hanokane are forged and welded, and struck and elongated to get four times the material, 20mm thick, 40mm wide, and 90mm long, and then cut into four.
Japanese: 下鍛えと2回目の積沸かし、上鍛えによって心金、棟金、刃金、側金の4種類の鋼が得られた後、棟金、心金、刃金の3層を鍛接して厚さ20mm、幅40mm、長さ90mm程の材料が4個取れるくらいに打ち伸ばし4個程度に切り離す。
English: Gawagane is also heated, and struck and elongated to become twice as long as the Core metal, and is then cut in the center to make two Gawagane of the same length as the Core metal.
Japanese: 側金も加熱され長さが芯金の倍になるくらいに叩き伸ばされ中央から切り離されて、芯金と同じ長さの側金が2本作られる。
English: Gawagane, Core metal and the other Gawagane are stacked in this order, heated, forged, and welded, then struck and elongated into a 15mm thick, 30mm wide, 500 to 600mm long plate.
Japanese: 側金、芯金、側金の順で重ねられ、沸かして鍛接されて、厚さ15mm、幅30mm、長さ500-600mm程度に打ち伸ばされる。
English: Teko' is cut off, then 'Nakago' which becomes the grip of a sword is heated, forged and welded.
Japanese: 「てこ」が切り離されて、刀の握り部分になる「なかご」が沸かされ鍛接される。
English: Sunobe,' is done by striking and elongating to form the shape of the Katana, and Kissaki (piercing tip) is made by cutting off the end.
Japanese: 刀の形に打ち延ばす「素延べ」（すのべ）を行い、先端を切り落として切先を作る。
English: Since this rough shape determines the final finished shape of a Japanese sword, it is carefully formed by striking with a Kozuchi.
Japanese: ここでの姿が最終的な日本刀の完成形を決めるため、慎重に小槌で叩き形を整えていく。
English: Mune (back) of the blade is struck to start the base of a triangular shape, and the blade side (Hirachi) is struck and elongated to reduce thickness.
Japanese: 刀身の棟は三角になるように叩いて、刃の側（平地）は薄くなるように叩き延ばす。
English: Then the Mune of the Nakago is struck to round the back edge, and lastly 'Shinogichi (ridge line)' is struck and formed.
Japanese: なかごの棟を叩いて丸みを付け、最後に「鎬地」（しのぎち）を叩いて姿を整える。
English: After it cools down, the black taint is removed by grinding with a rough polishing stone, and the Hirachi (blade) and Shinogichi (ridge line) are hammered using a Kozuchi (light hammer), and cold forging process is applied.
Japanese: 冷えてから表面の黒い汚れを荒砥石で砥ぎ落とし、平地と鎬地を小槌で叩いて冷間加工を行なう。
English: The straight lines of Mune and blade are adjusted, and unevenness is shaved with a special plane for shaving metal called Sen (銑, with the radical of 金 and 舌, by right).
Japanese: 棟と刃の直線を修正して、銑（正しくは金偏に舌、せん）と呼ばれる鉄を削るかんなで凹凸を削る。
English: As preparation for 'Yaki-ire (quenching)' to rapidly cool the heated blade with water or other liquid, 'Tsuchioki (soil coating)' where three types of Yakiba-tsuchi soil (soil used for quenching) are applied to the Hirachi (blade), Hamon (blade pattern) and Shinogichi (ridge line) are done.
Japanese: 加熱した刀身を水などで急激に冷やす「焼き入れ」の準備として、平地用、刃紋用（刃文用）、鎬地用の3種類の焼場土（やきばつち）を刀身に盛る「土置き」を行なう。
English: Yakiba-tsuchi soil (soil used for quenching) is applied thinly and evenly over the Hirachi (blade side), then Hamon (blade pattern) is designed with a writing brush using Yakiba-tsuchi soil for quenching for Hamon.
Japanese: 平地に平地用の焼場土を均一に薄く塗り、刃紋に筆で刃紋用焼場土を描く。
English: By using thicker concentration of Yakiba-tsuchi soil, for quenching, on the Shinogichi (ridge line), when cooling rapidly by Yaki-ire, the blade side is quickly cooled and quenched completely, and the Mune side is cooled relatively slowly and not fully quenched.
Japanese: 鎬地の焼場土を厚くすることで、焼き入れでの急冷時に刃側はすばやく冷やされ十分に焼きが入り、棟の側は比較的緩慢に冷えるために焼きはそれほど入らなくなる。
English: Quenching makes a sword harder, the metal expands, and creates the distinct curve of a Japanese sword.
Japanese: 焼きによって容積が膨張しながら硬くなり、日本刀独特の刃側が出っ張った湾曲を生む。
English: The Mune expands less, and takes on the property of tenacity rather than hardness, and this supports the blade side steel which is hard, but otherwise easily broken.
Japanese: 棟の側は膨張が少なく硬度より靭性に富んだ鋼となり硬いが脆い刃側の鋼を支える機能を担う。
English: Generally during Yaki-ire, Tosho dims the light of the workshop, and judges the temperature of steel by its glow.
Japanese: 通常、刀匠は焼き入れの時には作業場の照明を暗くして、鋼の温度をその光加減で判断する。
English: The blade coated with Tsuchioki is inserted deeply into the Hodo, and the whole blade from end to end is heated uniformly to about 800 degrees.
Japanese: 土置きした刀身を火床に深く入れ、先から元まで全体をむらなく800℃程度にまで加熱する。
English: The temperature is most important, and the optimal heat condition is checked with the greatest care, the body of blade is then plunged swiftly to a water tank and rapidly cooled.
Japanese: 加熱の温度は最も重要であり、細心の注意を払って最適の加熱状態を見極め、一気に刀身を水槽に沈め急冷する。
English: As mentioned above, the blade warps in the water, and it is pulled out after it is fully cooled, and is then ground with a rough polishing stone, and the Yakiba (焼刃, cutting edge) is checked.
Japanese: 刀身は前述の通り水の中で反りを生じ、十分な冷却の後に引き上げられ、荒砥石で研がれ焼刃が確認される。
English: After Yaki-ire (quenching), the surface of the blade is very hard and this is called Martensite.
Japanese: 焼き入れにより、刀の表面にはマルテンサイトと呼ばれる非常に固い組織が現れる。
English: Depending on how the Martensite looks, the Hamon (blade pattern) that looks like round particles on the surface of the metal to the naked eye, is called Nie (literally "boiling"), and separates from the Nioi (literally "scent") that looks like fine lines because the individual particles cannot be distinguished.
Japanese: マルテンサイトの入り方によって、肉眼で地鉄の表面に刃文が丸い粒子状に見えるものを錵（にえ）又は沸（にえ）と呼び、一つひとつの粒子が見分けられず細かい白い線状に見えるものを匂（におい）と区別する。
English: Other than water, some of other cutting tools are quenched in oil, and as were Japanese military swords during the war, but today, it seems to be reare that a Japanese sword is quenched in oil.
Japanese: 水以外にも、油で焼きを入れる事などが他の刃物類では有り、日本刀の場合では戦中の軍刀などで行われた事が有るが、現在では油で日本刀に焼きを入れる事が行われる事は少ないと思われる。
English: Although quenching in oil reduces failure, it is not suitable for modern swords that are meant to become a work of art because it cannot achieve a fine Hamon (blade pattern), apart from its sharpness.
Japanese: 油で焼きを入れると失敗は少ないが、刃文に冴えを出せず斬れ味は別として、美術工芸品を志向する現代刀には不向きだからである。
English: In this step, final adjustment is done by checking for small scratches, blade thickness and Jiba (blade surface).
Japanese: この時に細かな疵や、肉の付き具合、地刃の姿を確かめながら最終的な調整を行う。
English: Nakago (core) is finished with a Sen (a grinding tool) or a file, and for a Mekugi (fastening pin) hole used for securing the Tsuka (handle grip), usually one hole is drilled and two for a sword used for Iaido (Japanese martial art).
Japanese: 茎（なかご）は銑ややすりで形を整え、柄（つか）をはめる時に使用する目釘穴を普通は1つ、居合用の刀の場合2つ以上開ける。
English: Lastly, the craftsman carves his own name, address or year the sword was made on into the Nakago (core) as Mei (an inscription) with a Tagane (borer).
Japanese: 刀工は最後に鑿（たがね）を使い、自らの名前や居住地、制作年などを茎に銘を切る。
English: Generally, the name and address of the sword craftsman are inscribed on the front side (outside when wearing Tachi or Katana), and the year or name of the owner in the back side, but there are exceptions such as back-inscription or no inscription at all.
Japanese: 一般的に表（太刀や刀を身に付けた際、外側になる面）に刀工名や居住地を切り、裏に制作年や所持者名などを切ることが多いが、裏銘や無銘など例外もある。
English: This is the end of the work for the sword craftsman, then a Togi-shi (polisher) polishes the sword finally, but before the Muromachi period, the sword craftsman himself also polished the sword.
Japanese: これにより、刀工が行う一通りの作業が終わり、これからは研師により最終的な研ぎを行うが、室町時代以前は刀工自ら研磨も行っていたといわれる。
English: There is a big differences in polishing Japanese swords compared to other cutting tools; ensuring ornamental elements of a Japanese sword, as a craftwork, is focused on as well as assuming sharpness as a cutting tool, and the whole body, not just the blade part, is polished.
Japanese: 日本刀研磨は、他の刃物砥ぎと、かなり相異する点としては、刃物としての切れ味を前提としつつ、工芸品としての日本刀の美的要素を引き出す事を主眼としている点、刃部のみで無く、刀身全体に砥ぎを施す事等である。
English: Japanese swords are not completed soley by a sword craftsman, other craftsmen including a Togi-shi (polisher) and Saya-shi (Sheath craftsman) add the finishing touches.
Japanese: 日本刀は刀工だけが造るものではなく、研師や鞘師などの職人によって初めて完成するものである。
English: Tsuka (handle grip) has a part called Kurigata (literally "chestnut shape") for fixing Saya to an Obi (belt), which is used for attaching a cord called Sageo (literally "string downside").
Japanese: また、柄には鞘を帯に固定したりする用途で栗形と呼ばれる部分が付いており、下緒と呼ばれる紐を通して用いる。
English: The movement of pulling out a sword a littlie by placing the thumb on the Tsuba (handguard) when drawing a Japanese sword from the Saya is called "Koiguchi wo kiru (cutting the Koiguchi)."
Japanese: 日本刀を抜くときの所作で、親指を鍔にかけ、鞘から少し抜き出す動きがあるが、これを「鯉口を切る」という。
English: Most Japanese swords are single edged, and the side without blade is called Mine and the bulge between the blade and Mine is called Shinogi.
Japanese: 日本刀の多くは片刃であるが、刃のない側を峰（みね）と呼び、刃と峰の間の膨らんだ部分を鎬（しのぎ）と呼ぶ。
English: The part of the body of blade that fits into the Tsuka (handle) is called Nakago (core), which sometimes has an inscription of the name of the maker, called Mei.
Japanese: 刀身の、柄に収まる部分は茎（なかご）と呼ばれ、茎には時として製作者の名前が刻まれ、銘と呼ばれる。
English: Nakago has a hole to secure the body of blade to the Tsuka, which is called the Mekugi hole, and the small pin for securing is called Mekugi.
Japanese: また、茎には、刀身を柄に固定するための穴が開けられており、その穴を目釘穴、固定するための小片を目釘と呼ぶ。
English: When appreciating Japanese swords, the body of blade is especially paid attention to in most cases, and the appearance of the blade created when forging the sword is regarded as an object of art and named Hamon, Nie or Hada which is a pattern on the blade.
Japanese: 日本刀を鑑賞するときには、特にこの刀身に注目することが多く、刀を打つときにできた刃の様子を、刃紋、沸（にえ）、肌などと呼んで鑑賞の対象とする。
English: This is a part with an important role to cover the Nakago (core) and to ensure a good grip by the swordsman.
Japanese: 茎を包みこみ、使用者の握りを確かなものにするために重要な役割を持つ部分である。
English: Most of them are made of wood, covered with Tsukazame (shark skin), and tied with a belt-like thin cord called Tsukamaki (handle belt).
Japanese: 多くは木製で、その上を柄鮫を張り柄巻きと呼ばれる帯状の細い紐で巻いて構成されている。
English: The small piece to pierce and fix the Tsuka (handle) to the body of blade is called Mekugi, and the hole for piercing called the Mekugi hole.
Japanese: 柄と刀身を貫いて固定するための小片を目釘、通すための穴を目釘穴と呼ぶ。
English: The part of Tsuka (handle) closest to the hand is called Tsuka gashira (handle head), which usually has metal for both decoration and utility.
Japanese: また、柄の一番手元に来る部分は柄頭と呼ばれ、装飾と実用を兼ねた金属が付けられることも多い。
English: As a feature of Japanese swords, fittings (Koshirae) and the body of blade can be separated, and the body of blade is fixed to the Tsuba (handguard) by holding the part between Tsuba and the body of blade with Habaki (collar) and Seppa (washer).
Japanese: 日本刀の特徴として、外装品（拵え）と刀身を別々に分けることができる点があるが、この鍔と刀身の間をハバキや切羽などで押さえることで、刀身は鍔と固定されている構造となっている。
English: Japanese swords have repeatedly been transformed along with historical factors of the day including politics, economics, culture, manners and customs.
Japanese: 日本刀は、政治、経済、文化、風俗、習慣など、その時々の歴史的要因とあいまって変貌を繰り返してきた。
English: For example, iron swords and Tachi were excavated from the Inariyama tumulus, Saitama Prefecture and the Tsukuriyama tumulus, Shimane Prefecture, which is a large square tumulus in Izumo representing the early Kofun period.
Japanese: 例えば埼玉県の稲荷山古墳や島根県の古墳時代前期を代表する出雲の大型方墳である造山古墳(島根県)からは鉄剣、大刀が出土している。
English: The iron sword with a gold inscription excavated from Inariyama tumulus was made in 471 for commemorating the achievement working for Wakatakeru (Emperor Yuryaku) with 115 Chinese characters.
Japanese: 稲荷山古墳から出土した金錯銘鉄剣にはワカタケル（雄略天皇）に仕えた功績を記念して471年に作ったとの由来が115文字の漢字で刻まれている。
English: Although most swords of this period are corroded and damaged, Kanto Tachi with gold and bronze fittings excavated from Kawarake Valley in Yasugi City, Shimane Prefecture is miraculously in good preservation, and is famous as a rare case to pass the shine from the ancient days to the present with its golden Tsuka (handle) as well as the body of blade.
Japanese: この時代の刀剣の多くは朽損しているが、島根県安来市のかわらけ谷出土の金銅装環頭大刀は、奇跡的に優れた保存状態にあり、黄金色の柄をもち刀身さえも古代の輝きを今に伝える稀有な例として有名である。
English: Most swords after the seventh to eighth century retain their original form well, 'Heishishorinken' and 'Shichiseiken' of Shitenno-ji Temple and 'Kingindensono karatachi' of Shoso-in (treasure house of Todai-ji Temple) are well-known (Straight swords before appearance of curved swords are written as '大刀' instead of '太刀').
Japanese: 7世紀－8世紀以降の刀剣には原形を良く留めているものが多く、四天王寺の「丙子椒林剣」（へいししょうりんけん）や「七星剣」（しちせいけん）、正倉院の「金銀鈿荘唐大刀」（きんぎんでんそうのからたち）などが知られている（湾刀完成以前の直刀には「太刀」ではなく「大刀」の字をあてる）。
English: As Emperor Suiko composed, 'A colt from Hyuga Province is the best horse, and Masabi from Wu is the best Tachi,' swords from Wu (collective name of southeast area of China) was supposed to be the best during this period.
Japanese: 推古天皇が「馬ならば日向国の駒、太刀ならば呉のまさび」と詠んでいるように、この時代、呉（中国南東部の総称）の刀が最良とされていた。
English: In Shoso-in, domestically produced straight swords called Karayo (Chinese style) Tachi are stored as well as imports from overseas called Kara (Chinese) Tachi.
Japanese: 正倉院では唐太刀と呼ばれる海外からの渡来品と共に、唐様太刀と呼ばれる国産の直刀も保管されている。
English: Moreover, there still exist straight swords with Hirazukuri (ridged style) and Seppazukuri (front ridge style) and domestically produced Ken including Warabiteno Katana.
Japanese: また、平造り・切刃造りの直刀、蕨手刀（わらびてのかたな）といった国産の剣も現存している。
English: Although relics of swords from the early Heian period are scarce, and the transition of styles or how and when Japanese original curved swords were formed are not fully figured out academically, after the mid Heian period (around the 10th century), when the turmoil of Johei and Tengyo occurred, Warabiteno Katana (curved sword) which was easy to use when riding with its warped body of blade was used instead of conventional straight swords.
Japanese: 平安時代初期の刀剣の遺品は乏しく、作風の変遷や、いつごろどのようにして日本独自の湾刀が形成されたかについては、学問的に十分解明されていないが、承平天慶の乱などが発生した平安時代中期以降（10世紀ころ）従来の直刀に代わって騎乗時に扱い易い刀身に反りのある蕨手刀（彎曲刀）が使用されるようになった。
English: It seems that Warabiteno Katana that barbarians used while riding to the disputes with Tohoku where they suffered for a long time had an influence.
Japanese: これは長らく苦しめられた東北との紛争で俘囚が騎乗しながら使用していた蕨手刀が影響しているとみられる。
English: Also in this period, swords with 'Shinogizukuri' (ridged style) whose cross section of the body of blade is rhombic started to be made instead of the Hirazukuri (no ridge style) or Seppazukuri (front ridge style).
Japanese: また、平造り・切刃造りに代わって、刀身の断面が長菱形である「鎬造り」（しのぎづくり）の刀剣が造られるようになったのもこの時代である。
English: Kenukigata Tachi which has same steel in Tsuka (handle) and the body of blade, and Kogarasumaru sword which is warped with Kissaki-moroha zukuri (double-edged point style) were in a transition period of the change mentioned above (Kogarasumaru was mentioned in an ancient document as a work of 'Amakuni,' a sword craftsman in the early 8th century, but it is widely believed that it was in fact made in the mid Heian era.).
Japanese: 以上の変化の過渡期にあたるのが柄が刀身と共鉄の毛抜形太刀や、鋒両刃（きっさきもろは）造りで反りのある小烏丸（こがらすまる）である（小烏丸は古伝書には大宝(日本)年間（8世紀初頭）の刀工「天国(人物)」（あまくに）の作とあるが、実際の制作は平安中期と見るのが定説となっている）。
English: In the late Heian period, especially around the time of Early Nine-Years War and Late Three-Years War, Tachi was developed along with increasing power of samurai, and usually the ones after this period are called Japanese swords.
Japanese: 平安時代後期、特に武家勢力が活発になった前九年の役や後三年の役あたりから武家の勢力が増大し、これに伴い太刀が発達し、通常これ以降の物を日本刀とする。
English: Schools of sword craftsmenship appeared in the border area between Izumo and Hoki, and Bizen Province where there was good iron sand, and Yamashiro Province and Yamato Province which were the center of politics and culture.
Japanese: 良質な砂鉄がとれる雲伯国境地域や備前国と、政治文化の中心である山城国・大和国などに刀工の各流派が現れてきた。
English: Representative Japanese swords of this period are; 'Doji giri (killing ogre)' sword by which MINAMOTO no Yorimitsu cut Shuten-doji (Drunk Ogre) on Oe Mountain (made by Yasutsuna in Hoki Province, National Treasure); 'Kogitsunemaru (small fox)' sword which has a legend that a fox helped with the forging (made by Munechika SANJO in Yamashiro Province, lost during the Second World War).
Japanese: 源頼光が大江山の酒呑童子を斬ったとされる「童子切」（伯耆国の安綱作、国宝）やキツネに合鎚を打たせたという伝説のある「小狐丸」（山城国の三条宗近作、第二次大戦時に焼失）などがこの時期を代表する日本刀である。
English: Although an ancient document mentions that Yasutsuna from the border area between Izumo and Hoki who made 'Doji-giri' sword lived in the early 9th century, as seen in his existing work, it is widely believed that he didn't live in those days, but rather in the mid Heian period at the end of 10th century.
Japanese: 「童子切」の作者である雲伯国境の安綱は古伝書には時代を9世紀初めの大同年間（806年頃）とするが、現存作品を見る限りそこまで時代は上がらず、平安中期、10世紀末頃と見るのが刀剣史では通説となっている。
English: Other than Yasutsuna, SANJO Kokaji Munechika in Yamashiro (capital) and Tomonari KOBIZEN are regarded as the oldest sword craftsmen whose names are on existing work.
Japanese: 安綱のほか、山城（京）の三条小鍛冶宗近、古備前友成などが、現存在銘作のある最古の刀工とみなされる。
English: The style is Shinogizukuri (ridged style) with Iorimune (standard surface), having a short Kissaki (tip) called Sho-kissaki (small tip).
Japanese: 造り込みは鎬造り、庵棟（いおりむね）で、鋒（きっさき）が詰まって小切先となる。
English: The appearance is dignified (the tip is narrower than the hilt side) and elegant with big Koshizori (curve in the hilt side) and small curve in Monouchi (main cutting part).
Japanese: 姿は腰反りが高く、物打（ものうち）の方は反りが小さく、踏ん張りのある（元幅に比べて先幅が狭くなっていく形）優美な姿をしている。
English: As for Hamon (blade pattern), they have Suguha (straight temper line), or Kochoji (small clove hamon) or Komidare (small irregular hamon), which is called Nie.
Japanese: 刃文（はもん）は直刃（すぐは）または小丁子（こちょうじ）・小乱（こみだれ）が入っており、沸（にえ）出来である。
English: The width of cutting edge is not so wide, and Hamon usually starts a little ahead of Hamachi (notch at the beginning of the cutting edge).
Japanese: 焼幅はあまり広くなく、刃区（はまち）から少し先の方から刃文が始まっているものが多い。
English: Although Japanese swords in the early Kamakura era looked like the ones in the late Heian period, the military government system was established by the Kamakura Shogunate, and the world of swords blossomed.
Japanese: 鎌倉時代初期の日本刀は平安時代末期とあまりかわらない姿をしているが、鎌倉幕府による武家政治の体制が確立し、刀剣界が活発になっていく。
English: The Retired Emperor Gotoba established Gotoba-in smithery, where he summoned sword craftsmen each month and had them forge swords, also involved himself in Yakiba (cutting edge), and positively encouraged the making of swords.
Japanese: 後鳥羽上皇は後鳥羽院番鍛冶を設置し、月ごとに刀工を召して鍛刀させ、上皇自らも焼刃を施したといわれ、積極的に作刀を奨励した。
English: In the mid Kamakura period, as a result of emphasizing utility, the width of the blade became wider, which makes a difference in the width of blade at the base and at the top less, and swords have a rounded surface.
Japanese: 鎌倉時代中期になると、実用性を重視した結果、身幅が広く元幅と先幅の差も少なくなり、平肉がよくついてくる。
English: Kissaki (tip) became wide and short, which was called Ikubi (boar's neck), and showed a simple and strong characteristic.
Japanese: 鋒は幅が広く長さが詰まって猪首（いくび）となり、質実剛健の気風がよくでている。
English: Tanto from this period, had no curve, or it is slightly curved inward, and there are Nakago (core) without a curve and one in Furisode (kimono sleeve) style.
Japanese: この時期の短刀の特徴としては、反りがないか、わずかに内反りになっており、茎は反りのないものと振袖形（ふりそでがた）がある。
English: As famous swordsmith in this period, there were Kuniyoshi and Yoshimitsu of the Awataguchi school in Yamashiro, Kuniyuki, Rai Kunitoshi and Niji Kunitoshi (only 'Kunitoshi' was inscribed instead of 'Rai Kunitoshi' as signature) of Rai school also in Yamashiro, Shintogo Kunimitsu in Sagami Province, Fukuoka Ichimonji school in Bizen, Mitsutada of Bizen Osafune school and Aoe school of Bicchu Province.
Japanese: この時期の有名な刀工として、山城の粟田口派の国吉、吉光、同国来派（らいは）の国行、来国俊、二字国俊（銘字を「来国俊」でなく単に「国俊」と切る）、相模国の新藤五国光、備前の福岡一文字派、備前長船派の光忠、備中国の青江一派が存在する。
English: The creation of swords in these five provinces respectively have a unique feature in Jitetsu (steel), Kitae (forging) or Hamon (blade pattern), which are respectively called 'Yamashiro den (Swords from Yamashiro Province)' or 'Soshu den (Swords from Sagami Province).'
Japanese: これら5か国の作刀には、それぞれ地鉄、鍛え、刃文などに独自の特色があり、それを「山城伝」、「相州伝」などと称する。
English: It's a custom to call them 'Soshu den' instead of 'Sagami den' for Sagami Province.
Japanese: なお、相模国については「相模伝」とは言わず「相州伝」という習慣がある。
English: In the late Kamakura period, the creation of swords bloomed further due to disorders such as two Genko (Mongol Invasions) and collapse of the political system.
Japanese: 鎌倉時代末期、二度の元寇や政治体制の崩壊などの動乱により、作刀はさらに活気づく。
English: Japanese swords of this period were changing to become more dynamic than those from the mid Kamakura era.
Japanese: この時期の日本刀は、鎌倉中期の姿をより豪快にしたものに変わっていく。
English: The blade width became wider, which makes the width less at the base and at the top, and they came to have la onger Kissaki (tip).
Japanese: 身幅はより広くなり元幅と先幅の差も少なくなり、鋒が延びたものが増えてくる。