生野銀山史の研究

In the middle years of the sixteenth century mines of precious metals began so be exploited in Japan, and flourished for a century. Especially noteworthy was the vast output of silver. The silver mine at Ikuno in Tajima (now Hyogo Prefecture), discovered in 1542 was one of them. Having been worked for more than four hundred years, it is now under the management of the Mitsubishi Metal and Mineral Works. Back in the latter part of the sixteenth century (1580) the mine was in the hands of Hashiba (later Toyotomi) Hideyoshi and, when he had brought the whole land of Japan under his rule and establishad his own system of fiefs, it remained under his direct control. The number of mines of which he took possession was small, but to these mines he despatched special commissioners (Bugyo-nin 奉行人), who were entrusted to collect taxes--unjo-zei (運上税), as they were called--and for the collection they shared responsibility with similar officials in the service of the feudal lords of the districts in which the mines were located. The Ikuno Mine was, of course, not free from this feudal control, but on the other hand it was by this direct administration that it had attained, for example, as early as 1597 an annual production of silver amounting to some 10, 040 kg. Hideyoshi's policy was continued and carried forward by the Tokugawas, under whose iron rule most of the important mines of the country were made the domain of the first feudal lord (Shōgun). Such was the staus of the Ikuno Mine after 1600, until at last it came under the jurisdiction of the bailiff of the Shogunate with a feudal grant of 37, 000 koku in kind. The evidence suggests that in many of the mines which were worked in the latter part of the sixteenth century two systems of management prevailed: jiki-yama (直山) and uke-yama (請山). In the first case, the feudal lord to whom the mine belonged entitled the entrepreneurs to open pits upon conditions satisfactory to him. Arrangements were made as to the length of time for digging, usualy a month or so, and as to the payment of tribute, which was determined by bidding on the part of the entrepreneurs. In the second case, the right of the entrepreneur was more secure. The management of the whole mine was entrusted to him and he was entitled to hold it at least a year or so. Therefore, he could not only avail himself of the mineral resources but was also immune to the claims of the Shogunate and other feudal overlords, which were so cumbersome to jiki-yama entrepreneurs. To the silver mine of Ikuno the system of jiki-yama was first applied in 1583, but whether or not before that time another system was in practice we do not know. However, this year marks the beginning of an epoch in the increase of the silver production of the mine, and by 1600 the yield was as high as 516 kg per pit. The process of mining in this district was not very different from the system we have already spoken of. But at the same time it must be noted with regard to the increase of production that the newly invented method of mining was introduced from the Aikawa Mine in Sado, the greatest silver mine in contemporary Japan. At Sado the usual method of payment was called niwake (荷分) which originally meant the division of the output between the owner and the entrepreneur. The proportion was still undetermined in the early seventeenth century, but some evidence shows that the percentage of the payment of tribute ranged from one-third to one-fourth of the total yield. Of the payment at Ikuno we can not speak with certitude, but it is still assumed that the percentage was lower than that of Sado. Moreover, the entrepreneurs of Sado were awarded by the Shogunate with ample materials for the mining, and thus they were burdened with no expenses except for the wages of the laborors, while the entrepreneurs of Ikuno were subject to the whole cost of the mining operation. In those days at Ikuno a pit was divided into several sub-pits (tsubo 坪), and each sub-pit was further divided into sub-sub-pits called tokoro (所). The worker occupied such a niche in the pit, and the daily output of minerals which he dug was divided between himself and the entrepreneur. The tribute was paid out of the entrepreneur's dividend and the greater the dividend, the greater the amount of payment. But, generally speaking, it was only in the rich pits that this kind of payment was made. For the beginning of the seventeenth century, however, it is difficult to estimate the output of silver from the Ikuno Mine. A report of about the year 1622 says that there existed more than twenty rich pits with an output of silver ranging from 400 kg to 600 kg respectively, and that besides them many ordinary pits were also open. The refined silver was called haibuki-gin (灰吹銀) and all of it went into the hands of the Shogunate in exchange for silver currency (cho-gin 丁銀) during the latter part of the century. Meanwhile the upper strata of the mine with rich deposits of good silver were wor ...