■小栗上野介の業績 ■ Achievements of Kozukenosuke Oguri
中小坂鉄山の開発 　　（なかおさか　てつざん） Development of Nakaosaka Tetsuzan Iron Mine 中小坂鉄山　（群馬県甘楽郡下仁田町中小坂） Nakaosaka Tetsuzan (Shimonita town, Kanra county, Gunma Prefecture)
◇日本における製鉄は古来から砂鉄を原料としたタタラ製鉄でした。これは現在でも日本刀など切れ味鋭い刃物に向いた良質の鉄を得られることで知られていますが、製鉄法が大量生産には向いていません。 ◇１８６０万延元年の遣米使節小栗忠順らがアメリカで見た日本との違いは、大量の鉄を惜しげもなく使用している｢鉄の国アメリカ｣と、｢木の国日本」の違いでした。 　たとえば・・・町外れに捨てられた鉄製品を誰も拾わない／泊まったホテルの垣根が鉄でできている！／ワシントンの川にかかっている橋は鉄で、欄干も鉄。そういう橋があと４つ上流下流に見える！・・・と遣米使節一行の日記にあります。 ◇小栗が主張して帰国５年目に建設に着工した横須賀造船所の名称は、「横須賀製鉄所」から始まって｢横須賀造船所｣ー｢横須賀海軍工廠｣　と替わっている。明治４年までの「製鉄所」は買い込んだ銑鉄から〈あらゆる鉄製品を製する所〉という意味でした。明治５年に「造船所」となり、「製鉄所」は今の〈鉄鉱石から鉄を取り出す所〉となりました。明治４年までの「製鉄所」は要注意の歴史用語です。 ◇＜幕末＞ ・幕末の弘化嘉永頃から中小坂で鉄鉱石の採掘が始まった。 ・水戸藩では安政元年(１８５４)に反射炉を築造し、原料鉄として中小坂の鉄鉱石が運ばれた。 ◇小栗忠順は、いま計画が幕府に承認され建設工事が開始した横須賀造船所が出来れば良質な鉄がたくさん必要となる、日本を鉄の国にするには国内にいい鉄山はないかと調べた結果、中小坂の鉄山金久保山に着目した。 ◇1865慶応元年閏五月、小栗は勘定奉行連名で中小坂に鎔鉱炉を建設する許可願いを出した。 「…さいわい領主（松平摂津守・小幡藩主）も鎔鉱炉の建設、鉄山開拓を行いたい意向はあるやに聴いておりますが、鉱山の開拓は大変な手間がかかるものですから、小さな藩へ一任してしまって、その藩だけのわずかな必要分を目的とした高炉では産出する鉄の量も少なくなってしまうので、そういった方法ではなくすべて政府（幕府）の力で高炉を建設し経営していけばゆくゆくは産出量も多く潤沢になるはずでして、合わせて製鉄所や反射炉の生業も功を奏し追々国の利益となる・・・」と見込まれるので、「御英断をもって鎔鉱炉を建設する許可を下さるよう進言申し上げ・・・」（『陸軍歴史』）　と進言書を提出した。 ◇そして「武田斐三郎らが派遣され、持ち帰った中小坂金久保山の鉄鉱石を関口鉄砲製造所で分析試験をさせたところ、有害物資の含有もなく、我国にとってかつてない良質な磁鉄鉱」（『陸軍歴史』）との結果を得て、本格的な採掘の手配を開始した。 ◇「上州でもよりの石炭を産出する場所もありますが（当時石炭を用いることはなかったから）きちんとした試験掘りをして利用の可否を確定していないので、とりあえず燃料を木炭とし、上州甘楽郡西牧の御用林で焼いた木炭で賄う予定、・・・」（『陸軍歴史』）　で計画を進めた。
◇ Since ancient times, iron manufacturing in Japan has been based on tatara iron manufacturing, using iron sand as the raw material. This is still known today for its ability to produce high quality iron suitable for sharp cutlery such as Japanese swords. However, this method is not suitable for mass production. ◇ In 1860 (the first year of the Man'en Era), the Japanese envoy to the U.S., Kozukenosuke (Tadamasa) Oguri, and others saw in the U.S. the difference between "America, the land of iron," which sparingly used large amounts of iron, and "Japan, the land of wood. For example... In America, no one picks up iron products discarded on streets of town. A bridge over a river in Washington, D.C., is made of steel and has steel railings. They saw four more such bridges upstream and downstream! Those are the words in a diary of a member of the envoy to the U.S. ◇ Construction of the Yokosuka Shipyard, which Oguri insisted on building, began five years after he returned from the United States. The name of the shipyard changed from "Yokosuka Ironworks" to "Yokosuka Shipyard" and then to "Yokosuka Naval Arsenal." Until 1871, the word "ironworks" meant "a place where all kinds of iron products are made from pig iron purchased." The Yokosuka Ironworks became the Shipyard in 1872. The word of "ironworks" later became what we know today as "a place that extracts iron from iron ore. The term "ironworks" until 1871 is a historical term that requires attention. ◇ The end of the Edo period ・The mining of iron ore began at Nakaosaka Tetsuzan around 1850 at the end of the Edo period. ・The Mito clan built a reverberatory furnace in 1854, and iron ore from Nakaosaka was transported as raw material for the furnace. ◇ Tadamasa Oguri thought, "The Yokosuka Shipyard has been approved by the Shogunate and construction work has started. Once it is completed, we will need a lot of high-quality iron. In order to make Japan an iron country, I wonder if there are any good iron mines in Japan." He researched and focused his attention on the Kanakubo Mountain, an iron mine in Nakaosaka. ◇ In May in the leap year of 1865, Oguri submitted a request for permission to build a smelting furnace in Nakaosaka to the shogunate with other account magistrates (at the time, there were plural number of accont magistrates to avoid concentration of power). "Fortunately, the feudal lord (Matsudaira Settsunokami, Obata domain lord) was willing to construct a smelting furnace and develop iron mines. However, the development of mines requires a great deal of time and effort, and the amount of iron that can be produced will be small if the smelting furnace is left to a small clan to meet their own small needs. Therefore, if the government (the Shogunate) were to build and operate the smelting furnace entirely on its own, the amount of iron produced would eventually be large and plentiful, and the steel mill and the reverberatory furnace would benefit the nation. I would like to ask your permission to build the smelting furnace." ◇ Then, "Ayasaburo Takeda and others were dispatched to conduct analysis tests at the Sekiguchi Teppo Works on the iron ore brought back from the Kanakubo Mountain in Nakaosaka. The results showed that the iron ore contained no harmful substances and was of unprecedented quality for Japan" (Army History), and arrangements for full-scale mining were started. ◇ There was a coal-producing area nearby in Joshu (Gunma prefecture). However, since the feasibility of using coal had not been determined through proper test digging (since coal was not used in those days), the plan was rescheduled to use charcoal as fuel for the time being, and to use charcoal burned in the Imperial Forest in Saimoku village, Kanra county, Joshu. ("Army History")
◇＜明治維新＞ 　しかし小栗の中小坂鉄山の採掘計画はここまでで、明治維新・幕府解散によって中断し、明治政府に引き継がれて  本格的な操業が行われた。 ◇良質な磁鉄鉱と周囲から得られる豊富な木炭を燃料として,明治期に入ると本格的な操業が行われました。鉄鉱石を原料とする近代的製鉄が行われたのが中小坂製鉄所です。
◇ <The Meiji Restoration> 　 However, Oguri's plan to mine Nakaosaka Tetsuzan iron mines ended here, and was interrupted by the Meiji Restoration and the dissolution of the Shogunate, but was later taken over by the Meiji government for full-scale operations. ◇ Full-scale operations began in the Meiji period (1868-1912), using high-quality magnetite and abundant charcoal obtained from the surrounding area as fuel. Modern iron manufacturing using iron ore as the raw material was carried out at the Nakaosaka Ironworks.
＜明治以後＞ ・民間経営の時代・・・明治３年（１８７０）から本格的に採掘操業する者が現われ、明治７年に三条家の家令丹羽正庸は由利公正、三浦安らの経営参加を得、英人技師を雇って高炉、蒸気機関、熱風炉などを完成、スウェーデン人技師の技術指導で、トロッコによる水平移動により高炉炉頂へ運ぶ方式が取られた。
<After the Meiji Era> The era of private management: In 1870 (Meiji 3), a number of people began to operate mining operations in earnest. In 1874, Masatsune Niwa, the head of the Sanjo family, obtained the participation of Kimimasa Yuri, Yasushi Miura, and others in the management of the company, and hired English engineers to complete the blast furnace, steam engine, hot air furnace, etc. Under the technical guidance of the Swedish engineers, a method was adopted in which a trolley was moved horizontally to the top of the blast furnace.
中小坂製鉄所▲ 　　　明治１１年　　溶鉱炉があったことがよくわかる Left: Nakaosaka Ironworks in 1878 　Current view showing the smelting furnace		現在の風景▲ 対岸から見ると、左の写真と対比できる Right: View from the other side of the river, in contrast to the photo on the left
・わが国最初の蒸気機関による熱風送風による木炭高炉の操業、として唯一最大の製鉄所であった。　また高炉のほかに錬鉄炉、裁鉄、鍛鉄、銑鉄鋳造設備もそなえ、銑鋼一貫作業の形態をとっていたことも、わが国の製鉄史上特筆すべきことであった。 ・しかし採算がとれず人手に渡り、明治９年、由利公正が引き継いだが、輸入製品との価格競争があってやはり収支採算が取れず、明治１１年官営となる。 ・政府経営の時代・・・明治１１年官営製鉄所となったのちもやはり採算が取れない。高炉の耐火煉瓦が溶解、破損を繰り返ししばしば作業中断という状態であった。操業・故障を繰り返して１４年４月まで約１年９ヶ月に操業日数合計２５０日、銑鉄合計８５トンだった。 ・明治１５年、ついに廃業が決定。再び民間所有となり、経営者が何人か交替するも採算が取れず、明治４１年に生産中止、大正７年に設備がすべて撤去された。 ・昭和１０年代に再び採掘が行われたが、戦争終結で閉鎖となった。
It was the first and only ironworks in Japan to operate a charcoal smelting furnace using hot air blown by a steam engine. In addition to the smelting furnace, the plant also had a wrought iron furnace, cutting iron, wrought iron, and pig iron casting facilities, and its integrated pig iron and steel production was also noteworthy in Japan's iron manufacturing history. However, it was not profitable and was handed over to others. In 1876, Kimimasa Yuri took over the business, but due to price competition with imported products, and it became government-owned in 1878. The period of government management: Even after the ironworks became a government-owned ironworks in 1878, it was still unprofitable. The refractory bricks of the blast furnace were repeatedly melted and damaged, and work was often suspended. After repeated operations and breakdowns, the plant operated for about one year and nine months until April 1881, with a total of 250 days of operation and 85 tons of pig iron. In 1882, it was finally decided to close the business. The mine became privately owned again, and although several managers were replaced, it was unprofitable, production was halted in 1908, and all equipment was removed in 1918. Mining was conducted again in the 1940s, but it was closed down at the end of the war.
Ｅ．パウアー教授		ドイツ・マールブルク大学日本研究センター副所長で、技術史や日本経済史（日独の産業技術交流や日本の産業の発展）について研究し、東京大学社会科学研究所・客員教授もしています。 （２００５年３月６日調査）
Professor Erich Pauer is Deputy Director of the Center for Japanese Studies at the University of Marburg, Germany, and a visiting professor at the Institute of Social Science, University of Tokyo, where he conducts research on the history of technology and the Japanese economy (German-Japanese industrial and technological exchange and the development of Japanese industry). (Information obtained on March 6, 2005)
○資料 『陸軍歴史』 「中小坂鉄山研究上における問題点」一倉喜好…『双文』１〜3号・群馬県立文書館発行 『近代遺跡調査報告書ー鉱山ー』文化庁文化財部記念物課・平成１４年発行 『幕末明治製鉄論』大橋周治・アグネ・１９９１年２月刊
Documents Rikugun Rekishi (Army History) "Issues in the Study of Nakaosaka Tetsuzan," Kiyoshi Ichikurai..., Sobun, No.1-3, Gunma Prefectural Archives. "Report on the Survey of Modern Ruins - Mines", Monuments Division, Cultural Properties Department, Agency for Cultural Affairs, published in 2002. A Study of Iron Manufacturing in the Bakumatsu-Meiji Period", Shuji Ohashi, Agune, February 1991