Brunton Compass
Brunton
compass is a popular instrument used by geologists for surveying since
ages. The instrument was invented in 1894 by Canadian mining engineer D.
W. Brunton, and hence the name. Brunton compass was later commercially
develped by Brunton, Inc. of Riverton, Wyoming . Today however, the name
"Brunton compass" is referred to any type of pocket
transit compass even if they are manufactured by other companies.
Brunton compass, inspite of being expensive are considered indispensible
tool for the structural geologist.Components and sizes of Brunton compass
This compass is composed of delicate mirror and glass components which are vulnerable to shock and moisture thus, requiring care and periodic maintenance for proper application. Brunton compasses are available in a number of sizes which ranges from 8.5 cm(4 inches) in diameter and 5 cm thickness, 7cm(3 inches) in diameter and 4.5 cm thickness, 5cm(2 inches) in diameter and 4cm thickness.
Uses of Brunton compass
Geologists use this as an instrument for measurement of the altitudes of structural features. This compass helps in the visualization of lines and planes in three-dimensional space. There is a natural sine scale on the cover of this compass for calculations of different readings during a survey.
Reflective readings from the dial are acquired by the mirror placed under the cover of the compass while the level inside this tells us when the base of the compass is horizontal. The lever stituated inside the compass helps in adjusting the levels. The entire mechanism allows measurements of dip or plunge angles.
The Brunton compass is commonly used for the following:
- Field mapping of geological objects since they provide a precise sighting-clinometer and hand level capability and can be used both at waist and eye levels.
- It is used in mapping and measurement of stratigraphic sections.
- It is used to measure azimuth (compass bearing).
- The compass is used in mapping and measurement of vertical angles, percent grade, slopes, inclination of objects, height of objects and for leveling.
The brunton compass has been the geologists most trusted tool and it is considered an ideal instrument for carrying out surveys. This is still the finest and most respected field instrument for geologists, surveyors, miners, civil engineers, environmental engineers and forestors world wide.
