Yamamoto Lock Machine (formerly Yamamoto Iron Works) Second

Yamamoto Rock Machine (Former Yamamoto Ironworks) Factory No. 2

Factory No. 2 was built in 1937 at a right angle to the long shop that preceded it, running north from Factory No. 1 so that the two buildings meet in an L. Forty-four meters of workshop, single story, timber framed, with an iron sheet roof and a building area of 521 square meters. The Agency for Cultural Affairs record pairs the two buildings and calls them together the core of the plant.

The three years between the two shops were the years in which a country ironworks in Tojo turned into a manufacturer with a national market. Yamamoto Ironworks had begun in 1915 as a foundry casting household goods, moved on to engines and sawmill machinery, and then found its product when hydroelectric and dam construction on the Taishakugawa and Nariwagawa rivers brought imported rock drills into the Chugoku Mountains for repair. By the mid 1930s the company was building drills of its own design. Factory No. 1 went up in 1934, Factory No. 2 in 1937, and the business was incorporated with a capital of 1.3 million yen in February 1939.

Read in that sequence, the second shop is what a firm builds when the first one has filled up.

Why It Was Registered

Factory No. 2 was entered in the national register of Registered Tangible Cultural Properties on 25 February 2016, as No. 34-0157, in the 83rd round of registrations. It was one of eight buildings on and around the company's land registered that day.

Registration is not designation. The system was created in 1996 to bring a protective framework to modern buildings that the older designation regime, built around temples, castles and shrines, was never shaped to handle. Owners give notice before major alterations rather than seeking approval, and the expectation is that the building carries on doing its job. Every one of the Yamamoto buildings registered in 2016 was, and mostly still is, in use.

The criterion applied was contribution to the historic landscape of the country. In practice, what the assessors were looking at in Tojo was an unusually complete industrial group: two main shops, a finishing shop, a lavatory block, a training school, and a set of company dormitories across the road, all timber, all from a decade and a half of one company's growth. Factory No. 2 is the piece that gives the group its plan, turning a single long shed into a courtyard arrangement.

What to Look For

The roof structure is the point of difference. Where Factory No. 1 solves its lighting problem by splitting the section into three and raising the middle, Factory No. 2 spans its width with king post trusses, the type in which a single vertical member drops from the apex to the center of the tie beam, with struts running out to the rafters. It is the plainest of the standard truss forms and the most economical in timber for a span of this size.

Above the trusses runs a monitor roof, the same device used on the older shop, drawing off heat and adding light along the ridge.

Then come the windows. Double-hung sashes are ranged along the south gable end and both long sides, giving the elevations a rhythm closer to a school or an office block than a forge. The company's finishing shop, registered on the same day, took the idea further with a segmental arch over its south window and queen post trusses inside, and the pairing of the two makes a small lesson in how a provincial builder in the 1930s worked through the vocabulary of Western construction.

The wall finish repays a second look. The exterior is rendered in mortar, and the lower band, the dado, is finished in araidashi, a washed-out aggregate finish in which the surface is rinsed while the mix is still green to expose the stone. It is a labor-intensive technique associated with shopfronts and good houses, and finding it on a factory in a mountain town says something about how the company saw the building.

Access is limited. This is a working plant on private ground, without visitor facilities or regular opening. Preservation volunteers have organized occasional open days with the company, in some years alongside the Otoori festival in early November, when interiors have been shown for a small charge, but nothing about that is guaranteed from year to year. Contact the Shobara tourist association in advance if you hope to get inside. The exteriors, including the junction where the two shops meet, can be taken in from the public road.