station and the east and west cocoon plants. Main buildings Silk-reeling Mill (National Treasure) - This was the heard of the plant, and is a long and narrow building made from brick with wooden timber framing. The building is 140.4 meters in length, with a door at the eastern end, and is lot by large glass windows imported from France. The 300 reeling machines Brunat imported from France were installed inside. Although these were later replaced with newer technology from time-to-time, the building was large enough and did not need to be modified. Some of the original machines were given to other mill mills in Japan, and one was preserved at the Okaya Silk Museum. East Cocoon Warehouse (National Treasure) and West Cocoon Warehouse (National Treasure) are boilings on either side of the Silk-reeling Mill, with the three buildings arranged in a "U" shape. Both buildings were completed in 1872 and are two-story brick structures with wooden framing, and a length of 104.4 meters. As the name suggests, the upper floor of both buildings was used for storage of silkworm cocoons and could hold up to 32 tons. The ground floor of the East Cocoon Warehouse was used for offices, and the ground floor of the West Warehouse was originally used for coal storage. Steam Plant (Important Cultural Property) - The steam plant was also completed in 1872 and was located just north of the Silk-reeling Mill. It is another timber-framed brick structure. The single-cylinder steam engine introduced by Brunat is called the "Brunat engine", and is now exhibited at the Meiji-mura Museum. It was the main power source for the factory until its electrification in the 1920s. The chimney to the west also dates from 1872 and is part of the Important Cultural Property. Only the base remains, as the 36-meter structure collapsed in a storm on September 26, 1884. The present factory chimney was built in 1939. Water reservoir (Important Cultural Property) - The iron water tank is on the west side of the Steam Plant was is formed by riveting iron plates. It has a diameter of 15 meters and a depth of 2.4 meters, and has a masonry foundation. It has a water storage capacity of about 400 tons and is the oldest existing domestic cast iron structure. Drainage System (Important Cultural Property) - The sewage system for the plant was a brick culvert running north