| Bet Shean |
| Scythopolis |
| Conservation of the Mosaic in the Byzantine Forum |
| Duration | August 2006 - September 2007 |
| Implemented by: |
Ilan Phahima
Jacques Neguer - Conservation Guidance
Yoram Saad - Head of conservation project branch
Eli Liberty
David Azulai
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Remains of the ancient city of Bet Sheʽan (Nysa-Scythopolis; Scythopolis; Beisan) were uncovered in archaeological excavations the Hebrew University of Jerusalem conducted under the direction of Professors Yoram Tsafrir and Gideon Foerster from 1988 to 1996, and the expedition of the Israel Antiquities Authority, headed by Dr. Gabi Mazor. A massive conservation project was undertaken at the site between 1995 and 2004 and since 2004 conservation maintenance has been carried out on a regular basis.
The floor of the southeastern aisle of the Byzantine forum’s stoa (also called the agora) was exposed in an excavation that was carried out in 1993 by the archaeologist Dr. Walid Atrash. From the time the archaeological excavation conducted until the end of 2005 the mosaic and the remains of the walls that enclose it have stood exposed to the elements and mechanical damage.
The Byzantine forum extends northwest of the ‘Eastern Bathhouse’ and was probably erected in the latter part of the fourth century CE, at which time the Roman buildings that stood there were dismantled. The Byzantine forum, which is irregular in shape (45-55 x 115-130 m), was bounded from the southwest by the theater; from the southeast by the ‘Eastern Bathhouse’; from the northeast by the monumental altar, the nymphaeum and a temple; and from the northwest by the Palladius street.
The forum was an open public area in the middle of which was a decorative monument whose design and function are unclear. The monument stood atop a square base, remains of which were exposed. The forum was surrounded by stoae that delimited aisles paved with colorful mosaics. The aisles were 8 meters wide. The floor of the northwestern aisle was adorned with an illustration of wild animals that includes a lion, zebra, and gazelle. The floor of the southeastern aisle was decorated with geometric patterns and an inscription enclosed within a tabula ansata. The language of the inscription reveals when the mosaic was built: “the stoa was paved with a mosaic at the time of the most cautious governor Theodosius, son of Marcianus”.
Changes were made in the city at the beginning of the sixth century CE and in the Byzantine forum as well, especially along it southwestern side. The area of the forum was made narrower when a stoa was built across it which also damaged one of the corners of the inscription.
The Conservation Problems that were Identified in the Mosaic:
• Deterioration of the stone as a result of environmental factors such as: improper cleaning, water seepage, exposure to sunlight and temperature change.
• Peeling of stone as a result of flowing water, evaporation and temperature change.
• Crystallization of salt along the surface of the stone.
• Mechanical damage to the stone and cracking.
• Detachment of the tesserae layer from the bedding.
• Loss of tesserae.
• The absence of conservation intervention led a constant cycle of accelerating and deteriorating destruction of the remains.
The Principal Causes for the Deterioration and Destruction of the Artifact since its Exposure:
• The absence of conservation “first aid” at the time of the excavation (1993).
• Vegetation taking root. The artifact was not maintained and the vegetation was not eradicated which promoted the growth of weeds and reeds in the mosaic floor. This in turn caused the mosaic layers to separate resulting in the loss of tesserae.
• Faulty drainage. The drainage channels that cross the mosaic, which became blocked over time, led to water pooling on the surface of the mosaic, percolating into the mosaic bedding and ultimately causing the disintegration of the mortar and separation of the different layers that make up the mosaic.
The Conservation Measures Included:
• Cleaning the mosaic.
• Weeding the vegetation and spraying it with an herbicide.
• Stabilizing the edges of the mosaic.
• The following measures were taken in order to remove a section of the mosaic that had settled and return it to its original place: The surface of the mosaic and the joints between the tesserae were cleaned with water and a small brush. A thin dressing was glued to the area that was slated for removal. That particular area was marked and a scalpel was used to separate it from the rest of the mosaic. Afterwards, the mosaic was detached from the foundation layer and was removed on top of a sheet of plywood. Next the back of the mosaic was cleaned and a new foundation was constructed in accordance with the mosaic section that was removed – a layer of rock; a layer of rodus; a layer of tessellatum – and the mosaic was returned to its original location.
• Dislodged and fallen tesserae were returned to their place in the mosaic.
• The upper layer of the mosaic (the tessellatum) was stabilized with tesserae and mortar.
• Drainage was arranged as follows: Settled sections of mosaic were removed; the foundation was completed and the mosaic section that was removed was returned to its original level. A drainage pit was dug and the drainage channel that crosses the mosaic was cleaned. The sides of the channel were stabilized. A new foundation layer (rodus) was installed in the areas near the mosaic and in the missing sections and the area was properly graded.
• Wall stabilization: The loose mortar and dirt were cleaned from the joints between the stones. The joints were washed; unstable stones were reinforced and new mortar was added to the joints. Because of the weather at the site it was necessary to slow the drying process of the mortar by using wet cloth so as to prevent the new mortar from cracking and deteriorating.
To view the figures, click on the figure caption
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