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Bearing and Range Method ?Ij The bearing and range method utilizes a horizontal angle and a distance from one point to another to describe the second point's posi- tion. Angles may be described by a bearing or an azimuth. A bearing is the angle measured from either the north or south, toward the east or west, such that the reading is less than 90 degrees. For example, a north-east bearing would be read as N 450 E. The proper quadrant is shown by the letter N or S preceding the angle, and the letter E or W following it. An azimuth is an angle measured from north and may range from 0 degrees to 360 degrees. They do not require letters to identify the quadrant. Bearings are usually read from an instrument such as a Brunton compass or a transit. Azimuths are usually given by common pocket compasses. The system used is irrelevant, and largely a matter of preference for the field crew. It is important, however, to obtain "true" bearings or azimuths. Therefore, it is essential that the declin- ation of the compass is set correctly, and the declination used written in the field notes. The bearing and range system is particularly useful for identifying headstake locations relative to the benchmark. Figure A-14 shows a sketch of our hypothetical stream reach as it might appear in the field notes, giving headstake locations by bearing and range. SUGGESTED READING Two references were heavily utilized in the preparation of this appendix. For additional details concerning surveying techniques the reader is referred to Brinker and Taylor (1963) and Roth, et. al. (1977).1 'References cited in Appendices are listed in References following main text. S9