Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital

Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital

The Imperial Villa Garden Site of the Ancient Nara Capital (also known simply as the Imperial Villa Garden) was discovered in 1975 during an excavation made when the Nara Post Office building was moved. It was thereafter reburied, but then excavated again in 1985 to perform care and maintenance work and to reinforce and restore its scenic stones (keiseki). After this work was completed, exhibitions with the garden exposed to outdoor elements began. Nevertheless, with the passage of over thirty years, deterioration was once again observed.

Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty

 This garden was built around 750 AD and is thought to have existed until around 800 AD, the beginning of Japan’s Heian period.

The Imperial Villa Garden is an invaluable historic ruin discovered in the same form as it existed during the Nara period, approximately 1,200 years ago. It is an important time capsule conveying in unaltered form how people during that time thought about and aesthetically perceived gardens. Thus, not only are the scenic stones themselves very important, but so too are the position and angle that they are set in. As a result, the entire garden, including elements such as these, is subject to preservation.
                              
Thirty years later, this restoration work aims to restore the original beauty of the garden first achieved when it was initially restored. Restoration work is broadly divided into three stages.

1.) The positions of scenic stones that have become damaged or fragile are recorded. These scenic stones are then removed.
2.) Removed scenic stones are soaked in a reinforcing chemical agent. Stones that have come apart are bonded together with an epoxy resin.
3.) Reinforced scenic stones are replaced in their original position with millimeter-level accuracy.

Once it has been decided that part of the whole ruin will be restored, efforts begin first by conducting a survey and taking records at the location site.

Conservation and Restoration Work

It is important to make a complete record of invaluable information such as how people set these stones over 1,200 years ago.
(Caption: Scenic stone no. 37, Considering removal method)

Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital
Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital
(Caption: Scenic stone No.37
・Gravel and roots have penetrated the bottom
・Record and remove removable gravel
・Remove resin cured layer; wrap the sling around the scenic ・stone from the north and south sides
・Additional measurements for unrestored curb stones)
Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital
Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital
We place markers on important points of the stones and use a triangulation point as a reference to establish their position with.
When replacing the stones, these photographs and markers are important reference information to have.
(Caption: Scenic stone no.37, considering removal method)
Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital
(Caption: 37 Measuring surrounding stones)
Conservation and Restoration Work for Special Historic Site and Special Place of Scenic Beauty, the Imperial Villa Garden Site of the Ancient Nara Capital
(Caption: Scenic stone No. 37
・37-SO-01-17, coordinate records
・For 37-SO-18, photograph records only (no coordinates))
Conservation and Restoration Work
Next, the work of removing the stones begins.
(Caption: 37 Inserting a gap between stone and soil)
Conservation and Restoration Work
To avoid damaging the layer of soil around the stones as much as possible, stone removal is performed with caution and to the minimum degree necessary. At times like these, we rely upon the informed touch of the gardener, who handles scenic stones in his or her daily gardening. Work proceeds by anticipating how deep a stone is buried in the earth and what direction it is buried in.
(Caption 37: Inserting a gap between stone and soil)
Conservation and Restoration Work
When space begins to open around the perimeter of the scenic stone, the stone itself is wrapped up and conservation treatment is applied so that it does not become damaged.
(Caption: 37 Conservation treatment)
Conservation and Restoration Work
(Caption: 37 Conservation treatment)
Conservation and Restoration Work
Next the wrapped scenic stone is hoisted upward. This is an extremely advanced technique of traditional Japanese gardening still employed by gardeners today that uses a belt-shaped rope (sling) to change the direction that the scenic stone faces with complete control. It is a technique that requires great proficiency using just one rope to hoist a heavy rock so that it faces the angle that it needs to be set in.
(Caption: 37 Hoisting)
Conservation and Restoration Work
Damage not visible during other work is sometimes discovered while using this technique.
Conservation and Restoration Work
Here too, everything is recorded on the spot so that restoration may be performed later.
Depending upon the damage condition of the stone, the removal method may also be amended.
Conservation and Restoration Work
(Caption: Scenic stone No.37;
・Lift the scenic stone from the northwest side;
・Hoist it up again by setting the sling around its center)
Conservation and Restoration Work
Conservation and Restoration Work
The removal method is amended, and the scenic stone is lifted off the ground.
(Caption: 37 Hoisting)
Conservation and Restoration Work
The stone is quickly transferred onto a seat that has been prepared in advance, and conservation treatment is applied to the entire scenic stone so that important information is not lost.
(Caption: 37 Wrapping)
Conservation and Restoration Work
(Caption: 37 Conservation treatment)
Conservation and Restoration Work
Conservation and Restoration Work
The imprint left in the ground by the removed stone is also an important document. Everything is recorded.
Conservation and Restoration Work
If a support stone is wedged underneath a scenic stone, the way in which it is wedged is also recorded.
Conservation and Restoration Work
(Caption: 37 Wrapping)
Conservation and Restoration Work
The removed scenic stone is safely carried to the work area.
(Caption: 37 Transporting)
Conservation and Restoration Work
Conservation and Restoration Work
Every movement is taken slowly and carefully while carrying the stone.
Conservation and Restoration Work
(Caption: 37 Transporting)
Conservation and Restoration Work
The removed scenic stone is washed.
Conservation and Restoration Work
Stone fragments are also washed.
Scenic stones can sometimes be broken into as many as 600 pieces. Each one of these fragments is numbered and treated.
Conservation and Restoration Work
The fragment is then dried for a minimum of a week so that the chemical treatment can permeate the stone properly.
(Caption: Washing completed, no.75)
Conservation and Restoration Work
After drying is finished, this chemical treatment is permeated through the stone to supplement and strengthen the glassy substance inside the rock known as silicon.
(Caption: Material used, Reinforcement Agent OM25)
Conservation and Restoration Work
Small fragments are put in cups and impregnated.
Conservation and Restoration Work
Large items are placed in a net and treated before being impregnated.
Both small and large items are impregnated for three hours.
(Caption: Impregnation with Reinforcement Agent OM 25, No.75)
Conservation and Restoration Work
Conservation and Restoration Work
After impregnation, excess chemical treatment is wiped off to prevent discoloring.
Conservation and Restoration Work
The stone is then stored for a week away from direct sunlight and rainwater.
(Caption: Impregnation by Reinforcement Agent OM25 complete)
Conservation and Restoration Work
Once impregnation is completed, work begins to bond the fragments together.
An inconspicuously colored mortar or epoxy resin adhesive is used.
Conservation and Restoration Work
The color of the mortar material is changed to suit the stone.
Conservation and Restoration Work
Conservation and Restoration Work
This is what the stone looks like after bonding is finished.
Conservation and Restoration Work
(Caption: Restoration complete, No.75)
Conservation and Restoration Work
Completion of restoration work is checked.
(Caption: Checking completion of restoration work, No.37)
Conservation and Restoration Work
The restored scenic stones are reinstalled in their original positions.
The stones are transported safely to the reinstallation site.
Conservation and Restoration Work
(Caption: Place No.64, Measurement)
The information taken at the time of the stone’s removal is rechecked, and a method of reinstallation is discussed.
Conservation and Restoration Work
(Caption: Scenic stone reinstallation
No.37, considering reinstallation method)
Conservation and Restoration Work
(Caption: No. 37
Deeply embedded
There is a large stone fragment with a possibility of sticking in place → discuss after reinstallation, a discussion topic for the committee
Stone fragment 37 lifted last year: Is it a curb stone? A cobble stone? Check with person in charge.)
Conservation and Restoration Work
(Caption: Supplementing clay)
Conservation and Restoration Work
A coin minted in the year that restoration work was performed is inserted so that the year of the restoration work can be known even if all other documentation is lost.
Conservation and Restoration Work
(Caption: No.37, Position of the 10 yen coin)
Conservation and Restoration Work
The stone is hoisted on the belt-shaped rope (sling) and adjustments are performed so that the stone can be inserted at the angle desired by lowering it directly perpendicular to the ground.
(Caption: No. 37 Hoisting)
Conservation and Restoration Work
Conservation and Restoration Work
Marked points are identified using digital technology and a triangulation point and the stone is reinstalled within a 10mm margin of error.
Conservation and Restoration Work
Clay is supplemented as necessary.
(Caption: No. 37, Clay tamping)
Conservation and Restoration Work
Measurement error is corrected.
Conservation and Restoration Work
Reinstallation of the stone is completed.(Caption: reinstallation completed, 37)

This restoration work has been performed on seventy areas of the Imperial Garden Villa since 2014.
After restoration work is completed, the garden is scheduled to be reopened to the public so that it can be appreciated in its original form and used as a highly valuable research source.