Brunton compass

The United States Army has adopted the Pocket Transit as the M2 Compass for use by crew-served artillery.

Arguably the most frequent use for the Brunton in the field is the calculation of the strike and dip of geological features (faults, contacts, foliation, sedimentary strata, etc.).

Dip is taken by laying the side of the compass perpendicular to the strike measurement and rotating horizontal level until the bubble is stable and the reading has been made.

If field conditions allow, additional features of the compass allow users to measure such geological attributes from a distance.

As with most traditional compasses, directional measurements are made in reference to the Earth's magnetic field.