Examination of the Unified Silla system of quantity(量制) based on the ‘Sipseok Ipong(十石入瓮)’ Excavated from Wolji

The Sipseok Ipong(十石入瓮) is an artifact that provides an important clue to the understanding of the weights and measures of Unified Silla. The capacity of the Sipseok Ipong, ‘520ℓ’, and the ‘1 seung(升) = 350㎖’, ‘1 seok(石) = 15 du(斗)’, ‘1 seok = 520ℓ’ calculated from the Four-Dou-Five-Do(四斗五刀) marked bottles came to be commonly used in academia as the system of quantity(量制) of the late Silla period. In response to the question of whether the capacity of this artifact was really ‘520ℓ’, the actual capacity of the Sipseok Ipong was recalculated using the photo scan technique. As a result, the actual capacity of the Sipseok Ipong was found to be ‘721.5ℓ’, confirming that this is different from the existing common theory. If the capacity of the 8th-century relic, the 10-doo system(10斗制), is applied, ‘1 seung = 0.7215 ℓ’, and if applied as a 20-doo system(20斗制), ‘1 seung = 0.3607ℓ’, but if converted to stone, it was all 10 seok. Accordingly, the capacities of the 8th- and 9th-century large jars were calculated and substituted, but they could not be distinguished. As a result of tracing back through the 9th-century Four-Dou-Five-Do marked bottle with the volume specified, it was confirmed that ‘1 seung = 0.355ℓ’. It was confirmed that the 20-doo system was used in both the 8th and 9th centuries. Pottery capacitance analysis proved difficult to prove the 15-doo system(15斗制) used in the 9th century. The large jars excavated from the 9th-century Hwangryongsa Temple Site in Gyeongju and the Mireuksa Temple Site in Iksan have similar capacities, heights from the inner floor, and low diameters. The cause of this phenomenon was found in the use of the same standard applied to the Jeonggeumdae and the flat-bottom molding. The Unified Silla cheok(尺) is 29.5 cm, and when applied to the 9th century large jars, the height is 2.6 cheok, the diameter is approximately 0.9 cheok, and when converted to capacity, it converges to 2.9 seok. This is considered to be an example of the unified weights and measures used during the Unified Silla period. This kind of system of quantity study, which originated from the ‘Sipseok Ipong’ large Jar, can be used as basic data for understanding the economic system and social structure of Unified Silla. In the future, it is necessary to approach the system of quantity of the Unified Silla period more closely through comparative studies with artifacts used as Measuring device(量器).