Field notebook : Wyoming and Colorado
Page 32
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Transcription
Reading the Brunton Compass swight - Variation in Med. Town) 15 1/2 E, of True North. variation - angle between true north and magnetic north. decination - angle in verticle plane dip - toward magnetic field. standard at this position W90 90E N S 10° W. 1. Always read opposite the north end of the needle - 2. Before reading the number of degrees find between which 0's and which 90 the north end of the needle lies. 3. Read degrees.