Colotomy
![Ladrang form on the phrase making or colotomic instruments. p = kempyang, t = ketuk, ⋅ = pause, N = kenong, P = kempul, GONG = gong ageng.[1]](/uploads/202501/05/Ladrang_cycle0908.png)
![Ketawang structure as a clock diagram.[8]T = kethuk, P = kempul, N = kenong, Gong = gong ageng.](/uploads/202501/05/Ketawang_colotomic_structure0908.png)
Colotomy is a description of the rhythmic and metric patterns of gamelan music. It refers to the use of specific instruments to mark off nested time intervals, or the process of dividing rhythmic time into such nested cycles. In the gamelan, this is usually done by gongs of various sizes: the kempyang, ketuk, kempul, kenong, gong suwukan, and gong ageng. The fast-playing instruments, kempyang and ketuk, keep a regular beat. The larger gongs group together these hits into larger groupings, playing once per each grouping. The largest gong, the gong ageng, represents the largest time cycle and generally indicates that that section will be repeated, or the piece will move on to a new section.