| Answer | Crossword Clue |
|---|---|
| variometer | An instrument for measuring variations in the intensity of the earth's magnetic field |
| variometers | An instrument for measuring variations in the intensity of the earth's magnetic field |
| gradiometers | An instrument for measuring the gradient of an energy field, esp. the horizontal gradient of the earth's gravitational or magnetic field |
| gradiometer | An instrument for measuring the gradient of an energy field, esp. the horizontal gradient of the earth's gravitational or magnetic field |
| gaussmeter | an instrument for measuring the intensity of a magnetic field |
| gaussmeters | GAUSSMETER, an instrument for measuring the intensity of a magnetic field |
