by Jim Riesterer . . . . . . . . . . Edited by Scott Hughes, Dan Narsavage & Diana Boyack 

Topographic Maps TutorialIntroduction & MaterialsWhat is a Map?Using Topo MapsMap ScaleReference DatumMap ProjectionsDistortionsGrid SystemsGeographicUTMState PlanePublic Land SurveyVertical ScaleCreating ProfilesVertical ExaggerationCalculating SlopeUsing a CompassMagnetic DeclinationGet a BearingGo from A to BFind Self on a MapTopographic Maps Field ExercisesExercise 1Exercise 2Exercise 3Exercise 4GeoSTAC HomeField Exercisesgeostac@gmail.comApril 7, 2008 
Get a BearingA bearing is a measurement of direction between two points. Bearings are generally given in one of two formats, an azimuth bearing or a quadrant bearing. An azimuth bearing uses all 360° of a compass to indicate direction. The compass is numbered clockwise with north as 0°, east 90°, south 180°, and west 270°. So a bearing of 42° would be northeast and a bearing of 200° would be southwest, and so on. For quadrant bearings the compass is divided into four sections, each containing 90°. The two quadrants in the northern half of the compass are numbered from 0° to 90° away from north (clockwise in the east, counterclockwise in the west). In the southern half of the compass, the two quadrants are numbered away from south (counterclockwise in the east, clockwise in the west). Quadrant bearings are given in the format of N 40°E (northeast), S 26°W (southwest), etc. Whenever you measure a quadrant bearing, it should always be recorded with north or south listed first, followed by the number of degrees away from north or south, and the direction (east or west) away from north or south. In other words, you would never give a quadrant bearing as E 40°N or W 24°S. Your compass may be an azimuth compass or it may be divided into quadrants. If you have an azimuth compass and are given a quadrant bearing, you’ll have to divide it into quadrants in your head, and the same goes for quadrant compasses if you are given an azimuth bearing. Measuring a bearingSo, you’re in the field with your map at point A and want to get to point B…how do you accomplish this? The first thing you need to do is determine the bearing from point A to point B. There are two ways to go about this. 
The easiest way, is to carry a protractor with you when you’re in the field. If you have a protractor with you, place it on the map so it is oriented parallel to a northsouth gridline, with the center of the protractor on point A (or on a line drawn between points A and B). Once you have done this, you can simply read the bearing you need to go off of the protractor. If you don’t happen to have a protractor with you, you can determine the bearing you need using your compass. To do this, place your compass on the map so that the edge of your compass is oriented parallel to a northsouth gridline and the center of your compass is on the line between points A and B. Now rotate the map and compass together until the north arrow on the compass points to 0° on the graduated circle. You can then approximate the bearing you need by estimating where the line between A and B crosses the graduated circle. It is probably at about this point that, if you are using a Brunton compass (and some others as well), you are probably noticing that the ‘east’ label is on the wrong side of the compass (west of north). You are not hallucinating. It is that way for a reason that will become clear in the next section, hopefully. Continue to ... Getting from Point A to Point B ... 