Monograph No. 52
EXCAVATION AT SAIRYU-JI,AN ANCIENT NUNNERY NARA,JAPAN（1993）
RESEARCH REPORTS OF NARA NATIONAL CULTURAL PROPERTIES RESEARCH INSTITUTE, NO.52
English Table of Contents and Summary
Nara National Cultural Properties Research Institute (Nabunken) 1993
Note
Throughout the table of contents and the text, we use the following abbreviations: SA for feces and walls, SB for buildings, SC for corridors, SD for ditches, SE for wells, SG for ponds and reservoirs, SK for pits, and SX for other miscellaneous features, including ritually buried pottery and wooden troughs. We distinguish two types of structures, a post-hole type and base-stone type. In the former, a supra-structure is supported by pillars directly planted into the ground, and in the latter a supra-structure is supported by pillars standing on base stones.
Excavations at Sairyu-ji: an Ancient Nunnery in Nara, Japan
1993
Table of Contents
Chapter I: Introduction 1
1 History of investigations 1
A Investigations carried out between 1971 and 1973 1
B Investigations carried out between 1989 and 1991 1
2 Preparation of the site report 3
Chapter II: History of Sairyu-ji 5
1 Construction of the nunnery 5
2 Selection of the construction site and the arrangement of the nunnery compound 10
3 Sairyu-ji after the ninth century 13
Chapter III: Investigations 15
1 Excavations in the vicinity of the nunnery site 15
2 Overview of the investigations reported in this volume 20
3 Excavation log 22
A 209th Heijo excavation in the Nara Palace and Capital 22
B 210th excavation 23
C 212th excavation 24
D 219th excavation 25
E 221st excavation 27
F 223-4th excavation 27
G 227th excavation 28
H 228th excavation 28
I 223-21st excavation 30
Chapter IV: Site 31
1 Overview 31
2 Archaeological features 33
A Features dating prior to the seventh century A.D. 33
B Corridors surrounding the image hall and their vicinity 35
C Dining hall of the nunnery and its vicinity 40
Chapter V: Artifacts 47
1 Roof tiles and tiles 47
A Round eaves tiles 47
B Flat eaves tiles 56
C Miscellaneous roof tiles excluding the eaves tiles; tiles 65
D Round and flat roof tiles 67
E Roof tiles with inscriptions 68
2 Pottery and miscellaneous clay objects 70
A Pottery discovered in pits 70
B Pottery discovered in post holes 72
C Pottery discovered in reservoir SG530, earth filling the reservoir, and occupation debris accumulated over the leveled reservoir 73
D Pottery discovered in wells 76
E Glazed pottery and white porcelains 79
F Ink stones, penis-shaped clay objects, circular saucerl1ike objects, spindle-whorls, etc. 80
G Pottery with inscriptions in ink 81
H Pottery dating prior to 710 A.D. 82
3 Wooden objects 85
A From reservoir SG530 85
B From well SE491 86
C Frames of well SE491 recycled from door boards 86
4 Metal and stone objects 88
A Metal objects 88
B Stones objects 89
5 Artifacts associated with the feature of ritually buried pottery SX449 90
Chapter VI: Scientific Studies 91
1 Dendrochronology 91
2 Analysis of plant opal discovered at the Sairyu-ji site 92
A Samples 92
B Methods 92
C Results 92
D Discussion 93
3 Analysis of fatty acid remaining on pottery surface 94
A Introduction 94
B Soil samples 94
C Extraction of remnant fat 95
D Fatty acid composition in the remnant fat 95
E Sterol composition the remnant fat 97
F Quantitative analysis of the fatty acid composition 98
G Correlation of species for fatty acid composition 98
H Determination of glycolipids class by enzyme-linked immunosorbent assay (ELISA) method 99
I Summary 100
Chapter VII: Discussion 101
1 Sairyu-ji and the jobo gridiron urban system 101
A Jobo gridiron urban system before the construction of Sairyu-ji 103
B Arrangement of major buildings in the Sairyu-ji temple compound 103
2 Selection of the site for a new temple and its compound 105
3 Northeastern section of the compound which can be interpreted as a dining hall complex 109
4 Door boards discovered in well SE491 and their reconstruction to original door boards 113
5 Nature of the feature of ritually buried pottery SX449: an archaeological standpoint 115
A Context of discovery 115
B Questions raised against the results of fatty acid analysis 116
C Problem with the hypothesis that placenta was buried 119
D Ground-breaking ritual hypothesis 121
E Summary 122
6 Eaves tiles at Sairyu-ji in the 760’s and 770’s 124
A Structures roofed with tiles 124
B Pairs of round and flat eaves tiles 124
C Production and procurement of eaves tiles 128
7 Conclusions 137
Supplementary tables, supplementary figures
English table of contents and summary
List of Figures
1 Streets and avenues of the ancient Nara Capital in the vicinity of Sairyu-ji and the present condition 2
2 Excavation units in and around Sairyu-ji 16
3 Grid assignment in the excavation unit 6 BSR 20
4 Grid assignment and major features during the 209th Heijo excavation 22
5 Grid assignment and major features during the 210th excavation 23
6 Grid assignment and major features during the 212th excavation 24
7 Grid assignment and major features during the 219th excavation 25
8 Grid assignment and major features during the 221st excavation 27
9 Grid assignment and major features during the 227th excavation 28
Excavations at Sairyu-ji, an Ancient Nunnery in Nara
SUMMARY
This report summarizes the results of archaeological investigations carried out at the site of Sairyu-ji 西隆寺， an eighth to tenth century nunnery in Nara, Japan. Prior to the expansion and remodeling of a major department store and the construction of streets, staff of the Nara National Cultural Properties Research Institute (Nabunken) conducted eight excavations between 1989 and 1991 in the areas of the corridors surrounding the image hall, the dining hall and a part of the tamped-earth walls enclosing the compound. These excavations confirmed the existence of the east-side corridor at the previously anticipated location, and moreover, clarified changes in the arrangement of structures in the dining hall complex located to the northeast of the nunnery compound. Since Sairyu-ji is not well documented in written sources, the results of these excavations will shed new light on researches into ancient temples in Japan.
Overview of the Site
It is historically known that the construction of the Sairyu -ji nunnery began in 767 A.D. during the reign of Empress Shotoku 称徳. The nunnery was a national temple in a pair with the Saidai-ji 西大寺monastery and it occupied the ninth, tenth, fifteenth, and sixteenth blocks of the second ward on the first row avenue in the western sector of the ancient Nara Capital (in use 710-784), which was confirmed archaeologically during six excavations between 1971 and 1973, opening the area of 5434 sq. meters in total 1.
These excavations also revealed the foundations of the image hall, the pagoda, and the eastern gate. The image hall was situated on the north-south axis of the nunnery compound, which was along the alley between the tenth and fifteenth blocks. It was, however, a little off to the south of the east-west central axis of the compound. The foundation platform of the image hall measured 38.2 by 23.4 meters. The supra-structure can be reconstructed to a seven by four bay building standing on base stones.
Approximately 100 meters to the southeast to the image hall was the pagoda. The foundation of the pagoda measured six meters north-south by less than six meters east-west. The foundation platform was not preserved.
The eastern gate was situated a little off to the north of the east-west central axis of the nunnery compound, roughly 140 meters to the east of the image hall. The gate was elaborately constructed: the supra-structure of the gate was supported by four major pillars and eight minor pillars on base stones.
Inside of the eastern gate was a paved alley leading west to the center of the compound. The alley was 12.7 meters in width, and both sides were marked by tamped-earth walls. This suggests that the nunnery compound was divided into smaller areas enclosed by tamped-earth walls.
These major structures in the nunnery were already completed by 771 when the imperial government granted the official seal of Sairyu-ji. Historic sources record that Sairyu-ji was under the administration of Saidai-ji by 880, which indicates that the influence of Sairyu-ji had declined. Although Sairyu-ji still remained as of the tenth century, as of the tenth century. Yamato Saidai-ji Jiryo Kenchu-cho [Notebook of Examinations on the Saidai-ji Territory in Nara] dated to 1251 records that the site of Sairyu-ji was used as agricultural lands, meaning that Sairyu-ji had ceased to exist by that time.
The excavations, the results of which are reported in this volume, opened an area adjacent to and to the east of the image hall, and seven separate areas to the north and northeast of the image hall, all together 6067 sq. meters in total. In these areas, a part of the east-side corridor and the northeastern corner of the corridor enclosing the center of the Sairyu-ji compound, a complex of buildings related to the Sairyu-ji dining hall, and the northeastern corner of the tamped-earth wall enclosing the whole Sairyu-ji compound were discovered. These significant results have added greatly to our knowledge about the Sairyu-Ji nunnery.
Features Dating Prior to Sairyu-ji
Prior to the Nara Palace (710)
Features dating prior to the construction of the Nara Palace in 710 include a final Jomon Period ditch (ca. tenth to fifth centuries B.C.) (SD440) and a middle and late Kofun Period fence (SA442), buildings (e.g.SB441, SB536, SB551), and ditches (e.9.SD350, SD493, SD529, and a few minor ones), which are dated to the fifth and sixth century A.D. The Jomon Period ditch can be interpreted as being man-made owing to similar discoveries from the Yayoi Period (ca. fifth century B.C. to A.D. third century). The Kofun Period ditches may have been for irrigation purposes. Surrounding ditch SD350 of 3 meters in width, 0.45 meters in depth, for example, there are minor ditches parallel to and perpendicular to it, approximately 20 to 24 meters apart, which might have demarcated individual rice paddies. There were a group of residences surrounding ditch SD529 in the sixth century.
Nara Period before Sairyu-ji was constructed (710 to 767)
Residences occupying the second ward on the first row street of the western sector of the Nara Capital were discovered. A noteworthy example was SB510, a north-south oriented post-hole type structure with a roofed veranda (hisasi 廂 2) on the east side， which was the largest structure in this area of the Nara Capital dating to this phase. The Kofun Period ditch SD529 was turned into the reservoir SG530 during this phase, and was filled up when the construction of Sairyu-ji began in 767.
Features Related to Sairyu-ji (767 to ca. tenth century)
Corridors surrounding the image hall
Parts of the north-side and east-side corridors surrounding the image hall of the Sairyu-ji nunnery were discovered. The corridors were “double or composite” corridors 3 (Fukuro 複廊) on 16 shaku 4 尺 or 4.8 meters in width. The north-side corridor is reconstructed to be 260 shaku or 77.8 meters, and the east-side corridor to be 286 shaku or 84.8 meters. The east-side corridor had 27 bays or spaces between two columns. It remains in question whether or not the north-side corridor was connected to a lecture hall of the nunnery, which is presumed to have been situated due north of the image hall.
Dining hall complex in the northeastern part of the nunnery
Between the corridor surrounding the image hall and the tamped-earth wall enclosing the entire nunnery compound in the northeastern part was a dining hall complex. The complex was built after the reservoir SG530 was filled, and the ground was leveled. The complex was enclosed by a tamped-earth wall in four directions. Careful stratigraphic analysis made it possible to discover that the structures in the dining hall complex were once modified although it was impossible to determine the calendrical date.
Phase a (before the structural modification)
The main hall of this complex was the post-hole type building SB490A, a northern part of which was revealed during our excavation. It was oriented east-west and was seven bays in width (70 shaku or 21 meters). SB490A was surrounded by three post-hole type buildings SB485, SB495, and SB520 in three directions (to the east, north, and west respectively). All of them were five by two bay buildings. Behind SB495 to the north was a seven by two bay post-hole type building (SB505, 14.7 by 4.8 meters in plan), which was enclosed itself by a fence (SA506).
Owing to the close similarity in the structural arrangement to that of the Saidai-ji dining hall complex which was well recorded in historic sources, the main hall SB490A is attributed to be a jikido (食堂 dining hall), SB495 to be a tono (殿 pantry), SB505 to be an oitono (大炊殿 administrative building), SB485 to be a higasi no kuriya (東厨 eastern kitchen), and SB520 to be a nishi no kuriya (西厨 western kitchen).
Phase b (after the modification)
The Sairyu-ji dining hall complex was completed during this phase when the major buildings, including the dining hall and the kitchen(s), were turned into heavily constructed structures standing on base stones. SB490A was replaced with a base-stone type building of the same size with a roofed veranda (SB490B). To the west of SB490B, the western kitchen SB520 was once demolished, and instead, the minor base-stone type building SB521 was erected near the site of SB520. The eastern kitchen SB485 was replaced with the base-stone type building SB480. It was oriented north-south, and was a nine by four bay building with roofed verandas on both the east and west sides. The nature of SB480, however, still remains in question as to whether it was a large kitchen or an administrative building. The pantry SB495 was replaced with a large post-hole type building of seven by four bays, with roofed verandas on both the north and south sides (SB500), whose function probably remained as a pantry.
In a space between the dining hall, administrative building, and kitchens was the large well SE491. The use of this well continued until the tenth century, which suggests that Sairyu-ji existed until then.
Tamped-earth walls enclosing the nunnery compound
It is likely that the entire nunnery compound was enclosed by tamped-earth walls. A part of the east-side wall (SA420) and traces of a part of the north-side wall were excavated. The width remains unknown. The discovery of a base stone on the north-side wall (SB608) suggests that a gate was provided on the north side.
Discussion: Nature of the Sairyu-ji Nunnery
Sairyu-ji was erected in a pair with Saidai-ji by Empress Shotoku’s order in the late Nara Period (the 760’s and 770’s). The former was meant to be a national nunnery, and the latter to be a national monastery. For this reason, the temple compounds of the two were anticipated to be very similar. Indeed, the excavations revealed that the Sairyu-ji dining hall complex was extremely similar to that of Saidai-ji. Roof tiles excavated at Sairyu-ji also strongly suggest a close relationship with Saidai-ji. Sairyu-ji and Saidai-ji were found to share six types of eaves tiles produced with ten molds (e.9.Fig.61, a pair of types 6235C and 6761A). Since none of the Sairyu-ji eaves tile types were used in Todai-ji, it is likely that craftsmen in charge of the roof tile production for Saidai-ji were involved in the production of roof tiles for Sairyu-ji in the 770’s. (In the 760’s when the construction of Sairyu-ji started, however, the roof tile production for Sairyu-ji was conducted by craftsmen who were involved in the roof tile production for the Nara Palace.)
Despite these similarities of Sairyu-ji to Saidai-ji, Sairyu-ji had some unique features. Excavations yielded types of eaves tiles that were not used at Saidai-ji (e.9.P1.30, type 6125A and P1.39, type 6775A). The Sairyu-ji compound was much smaller than Saidai-ji, estimated at 260 by 230 meters for the former as opposed to 400 by 500 meters for the latter. The arrangement of buildings in the Sairyu-ji nunnery was different from that of Saidai-ji. For example, while the former only had one image hall surrounded by corridors, the latter had two which were connected by corridors. Accordingly the specific nature of Sairyu-ji in comparison to Saidai-ji still remains to be debated, and the excavations have provided data contributing to this debate.
In conclusion eight excavations carried out between 1989 and 1991 contributed to understanding about the Sairyu-ji nunnery which is not well recorded in historic sources. The excavations resulted in the discoveries of the east- and north-side corridors surrounding the image hall, the dining hall complex, and the northeastern corner of the tamped-earth walls enclosing the nunnery compound. These results revealed some aspects of Sairyu-ji which were shared with Saidai-ji, and also some aspects which were unique to Sairyu-ji. The results will be useful in interpreting the nature of this nunnery.
1 KUROSAKI Tadashi, Editor. 1976. Sairyu-ji Hakkutsu Chosa Hokoku [Report of Excavationsat Sairyu-ji]. Ad Hoc Committee for the Sairyu-ji Investigations, Nara.
2 Hisashi is a narrow aisle-like area outside of the core (moya) of a building. Throughout the text it is referred to as a “roofed veranda.”
3 Although a single structure, a fukuro is divided into two corridors by an earthen wall with windows. The whole structure is supported by three rows of columns.
4 A unit of length in premodern Japan. During the Nara Period, one shaku equaled approximately 30 cm.
1993年３月30日 発行
西隆寺発掘調査報告書
奈良国立文化財研究所40周年記念学報 第52冊
