| Answer | Crossword Clue |
|---|---|
| altazimuth | an instrument for measuring the altitude and azimuth of heavenly bodies |
| altazimuths | ALTAZIMUTH, an instrument for measuring the altitude and azimuth of heavenly bodies |
| sextants | an instrument for measuring angular distances used especially in navigation to observe altitudes of celestial bodies (as in ascertaining latitude and longitude) |
| barometer | An instrument measuring atmospheric pressure, used esp. in forecasting the weather and determining altitude |
| barometers | An instrument measuring atmospheric pressure, used esp. in forecasting the weather and determining altitude |
| barometry | an instrument for determining the pressure of the atmosphere and hence for assisting in forecasting weather and for determining altitude |
