Hook gauge

{
  "id": "MLC-T-MET-006272",
  "term": "Hook gauge",
  "field": "Meteorology and atmospheric science",
  "definition": "A precision instrument used to measure the water level in stilling wells or open channels with high accuracy. It consists of a sharp-pointed hook attached to a movable scale, which is lowered until the tip just breaks the water surface. The reading is then taken from the scale, providing measurements typically accurate to within a few hundredths of a millimeter.",
  "url": "https://mlchart.com/terminology/meteorology/hook-gauge/"
}