ID: 
2248
Maker's Name: 
Paulin Instruments
Where made: 
Sweden
Dimensions: 
12.8 × 12.8 × 7.5 cm

Aneroid barometer where the measurement is made by manually adjusting the force of a spring to balance the force of the atmosphere on a bellows. This avoids any problems with friction.

The black knob is turned until the needle in the little window at the 12 o'clock position is centred. The altitude can then be read off the circular dial that reads -180 to +1400 m altitude (or 66 to 79 cm Hg. pressure)