The rules governing the relative proportions of parts when a wooden statue is made by the joining of several pieces of wood (see *yoseki-zukuri 寄木造). Before cutting begins, the size, dimension, and number of blocks of timber needed for the final sculpture are calculated. These blocks are then carved to form separate parts of the statue: the feet, back, trunk, head, etc. The parts are then joined together *hagitsuke 矧付. Because the measuring is done in advance, the cutting work can then be divided between many carpenters for greater efficiency. The great 11th-century sculptor Jōchō 定朝 (?-1057; see *Jōchōyō 定朝様) is especially famous for developing and perfecting the kiyosehō method. In the case of the Amida Nyoraizō 阿弥陀如来像 in Byōdōin *Hōōdō 平等院鳳凰堂 (1053), Kyoto, a representative work by Jōchō the front of the statue is made from two vertical sections of timber (divided left and right) and the back from another two vertical pieces (also divided left and right). The feet are also made from two pieces of timber, which are split from side to side, so that the backs of both feet are carved from one block, and the fronts from another. Although some later works use more complicated structures, such as separate blocks for sections of the head, or smaller divisions of the trunk, the basic pattern of kiyosehō established by Jōchō was used until the Edo period.