Teluktak [ketongan air]
- Andrew C. McGraw
Sonic alarm used in traditional Balinese rice irrigation. It is a bamboo tube about 60 cm long and 6 cm in diameter closed above the midpoint by a natural node and cut at an angle at the open top. The tube pivots in a simple wooden frame on a wooden axle passing through the tube just below its midpoint. A stone is placed beneath its lower end such that the tube rests at an angle of about 45 degrees. The open end is placed under a small stream of water descending from a higher to a lower rice-field terrace. As the water redistributes the tube’s weight, the upper end tips downward, emptying the water, then quickly turns upright so that the lower end of the tube strikes the stone, producing a sharp percussive tone. Several teluktak might be placed side by side. The cessation of the teluktak’s tones warns a farmer that the irrigation system might need repair....