What measures Air pressure?

Air Pressure can be defined as the pressure of air in the earth's atmosphere. It reaches a maximum of about 100,000 Pa near sea level and decreases as altitude increases.

The barometer is an instrument which is used for measuring Air pressure.

Physics instruments and their uses:

Barkometer  - - - Tanning liquors used in tanning leather

Bolometer  - - - Electromagnetic radiation

Spectrometer - - -  Properties of light.