PURPOSE: To determine the declination and the inclination of the earth's magnetic field.
DESCRIPTION: Both magnetic declination and inclination, or dip, can be measured with good precision using this well-made instrument. The strongly magnetized needle is 10 cm long and mounted on sapphire bearings at the center of an 11-cm circular ring graduated to single degrees to indicate inclination. This ring is mounted on a horizontal diameter and is free to turn on a tapered bearing in the center of a tripod base, a 6-cm disk on the base being graduated to 5-degree divisions to indicate declination. The instrument is equipped with levelling screws and a spirit level for making the pillar accurately vertical. The over-all height is 28 cm. (from Sargent Welch catalog)
SUGGESTIONS: May not give accurate readings in buildings due to steel construction beams.
REFERENCES: (PIRA 5H10.15)
EQUIPMENT: Declination and inclination needle.
SETUP TIME: None.
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