Taito City Culture Guide Book, Relaxing at the Tokyo National Museum

Preservation of cultural properties is carried out with daily research and years of accumulation.

"Seishitsu Ginryu Suimon Handachi no Daisho Koshirae" / the 16-17th century (Azuchi Momoyama - Edo Periods)

Honkan, Room 13 / Swords

Honkan, Room 13 / Swords

Kanba: This is the section of swords. There are many enthusiastic sword lovers. This is a sword designated as a National Treasure. The sword shape is beautifully preserved. This item was made in the Heian Period (11th century). This is an important art object. This sward was made in the Kamakura Period (13th century). This sword shape is also beautifully preserved. This was also made in the Kamakura Period (13th century). All of them were made more than 700 years ago. It is wonder that, even to this day, these swords have retained perfect shapes without any rust and have glittered. Since swords are made of iron, they rust very easily. If swords are left without any treatment, they rust soon, their overall surfaces become brown and some parts of them are decomposed. Therefore, in order to avoid such deterioration, swords should be constantly cared. If swords have not been cared and become rusty, the rusty parts should be grinded. The degrees of abrasion of swords vary depending on how many times the blades have been grinded since the Heian Period. If swords had repeatedly become rusty, the blades of the swords would have been gradually worn away. Yet, the swords displayed here are not worn away because they have been scarcely grinded. What it means is that it is the evidence that the swords have been constantly checked and cared to prevent rust. If the swords had not been checked and cared in such a way, these swords would have become very thin like needles.

Q: How many swords are stored in this museum? Are those swords regularly grinded or cared?

Kanba: This museum has about 1,000 legacy swords. It is impractical to care all the swords in a short period of time, so we have regularly cared the swords little by little. Although this museum has a history of about 140 years, the important thing is that how the swords had been cared before the opening of this museum. In other words, it is how the swords had been checked and how damaged portions had been treated, which are closely related to "preventive conservation" that we have now thought of. The swords should have been regularly cared in order for them not to be damaged, or not to become rusty, and should not grind them after being damaged. By doing so, the shapes of the swords have been finely maintained for several centuries. These swords display good examples of "preventive conservation" that we aiming at. (continued in the lower column)

Q: If I touch the case, does it actually move? Is the item in the case just placed in it? Is it not fixed?

Kanba: Yes, it moves. The reason why the cover of the lower part can come off is that, when the device moves, the whole cover is pushed out. The cultural property is just put in the case. All the display cases in this museum have this kind of base-isolating device, so individual measures to prevent items from toppling are not needed. However, it is needless to say that additional measures might be needed depending on shapes of items.

Q: What magnitude of earthquakes do you anticipate?

Kanba: This base-isolating device can adequately withstand horizontal shaking caused by an earthquake equivalent to the Great Hanshin Earthquake, which horizontal acceleration was about 800 to 1,000gal.

Honkan, Room 10 / Ukiyo-e and Constume

Kanba: Pieces of Ukiyo-e, kimonos with short sleeves and ornamental hairpins, that are to say, customs of townspeople in the Edo Period, are displayed in Room 10 in Honkan. Pieces of Ukiyo-e are displayed on this wall. Kimonos with short sleeves are displayed on that wall. Kimonos with short sleeves and pieces of Ukiyo-e are displayed in the same room because both of them represent customs of townsfolk in the Edo Period. Also, in terms of a preservation perspective, there is an important thing. That is to say, natural dyes were used for both of them. Kimonos with short sleeves were dyed by natural dyes and weaved. Ukiyo-e was also printed using natural dyes. Besides pigments, natural dyes were used for the paper on which Ukiyo-e was printed, and natural dyes were also used for the silk with which kimonos with short sleeves were weaved. So, both of them have similar characteristics. They are very vulnerable to light. Natural dyes are easily faded by strong light. These pieces of Ukiyo-e and kimonos are placed together because their preservation requires a certain level of darkness. In terms of preservation, this section is maintained in an appropriate condition. (continued in the lower column)

Pot created by Ninsei that is protected by the base-isolating device

The base-isolating device

Section of Ukiyo-e

Ukiyo-e and costumes are displayed while being protected by delicate lighting and devices.

As for the desirable brightness, complete darkness is the best for preventing the items from fading. The brightness is expressed in the unit "lux." However, visitors cannot see items in complete darkness. Therefore, it is a matter of a level of brightness. The brightness of 50 lux is appropriate for Ukiyo-e. Visitors can somehow appreciate colors, shapes and atmosphere of items at the level of 50 lux. These pieces of Ukiyo-e are also displayed at the level of about 50 lux. If a room is dark, it is safe for items, but it is difficult for visitors to see them. What is the best way to appropriately preserve and display items while providing sufficient visibility of items? That is the question we should answer. In order to preserve and display items in an appropriate way, this display case was created. This is not a simple frame but a display case. Although it is very thin, but is a frame-type display case. It looks as if there is no glass. A low-reflection glass is used for the case, so there is almost no reflected light. Viewers feel as if they directly look at Ukiyo-e. You can come close and look at it. This glass is not broken even if it is beaten. The light is also cast from above and underneath. The light is evenly distributed over the whole surface, so it is very easy to look at it. Although the room is dimly lit in order to preserve items, we take measures to appropriately show the items.

When you look at Ukiyo-e from a long distance, the details cannot be seen. You can see printing techniques such as goffering, if you closely look at Ukiyo-e. This exhibition makes that possible.

Display case with the base-isolated structure

Kanba: This is a pot created by Ninsei, which is the one of the representative exhibits in this museum. This pot has a beautiful shape and patterns, but, in a sense, its shape is extremely vulnerable to earthquakes and vibrations. Its base is very narrow, and the position of the center of gravity is relatively high, so it topples easily. If the base-isolating device is not installed, we should devise some way to prevent the pot from toppling as a measure of precaution. For example, the pot might be fixed by stretching nylon fish lines from the pot to the four corners of the case. You may see such a display method at other museums and this museum, but that method should be preferably avoided in order for visitors to focus on exhibits themselves. Therefore, all individual display ceases in this museum are quipped with base-isolating devices, which absorb shocks of earthquakes; the whole cases do not shake, and only the devices shake during earthquakes. The devices can horizontally move in every direction. (continued in the upper right column)