ELEMENTARY MAP AND COMPASS A) Why is a map and compass necessary? A map and compass are navigation aids. They are necessary for navigation to a wilderness destination and returning safely and efficiently. On a well planned trip, the location of creeks and rivers to be crossed, ridges to be climbed, barriers to be bypassed, distances to traverse, landmarks to guide the way, and elevations to conquer, can be determined before commencing. B) What is a topographical map? A map is a representation of the Earth (or part of it), and is plotted to a definite scale. Traditionally, maps have been printed on paper, but they are also available on the computer. When a printed map is scanned, the computer file that is created may be called a digital raster graphic. A topographical map is a two dimensional, detailed, graphic representation of part of the earth’s surface including a portrayal of the shape and elevation of the terrain. The distinctive characteristic of a topographic map is that the shape of the Earth's surface is shown by contour lines. Contours are imaginary lines that join points of equal elevation on the surface of the land above or below a reference surface such as mean sea level. Contours make it possible to measure the height of mountains, depths of the ocean bottom, and steepness of slopes. A topographic map shows more than contours. The map includes symbols that represent such features as streets, buildings, streams, and woods. These symbols are constantly refined to better relate to the features they represent, improve the appearance or readability of the map, or to reduce production cost.

The portion of the Elizabethtown, Kentucky, area shown here demonstrates how map symbols represent features on the Earth's surface. The bottom third, an aerial photograph, shows the Earth as seen from above; the middle part portrays some of the features on the aerial photograph that will be symbolized on the map; and the top third shows the finished map as a digital raster graphic.

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C) What is a compass? A compass is an instrument used for indicating and determining direction. It consists of a freely suspended and pivoted magnetized needle that points in the general direction of the magnetic North Pole under the influence of the magnetic field of the earth. Typically the needle has a dark end and a light end, but each compass type may be different. The dark end points toward the general direction of magnetic north. Several appurtenances that are frequently added to an orienteering compass, to aid in its efficient and accurate use in the field and in conjunction with a map, include the following: 1) A rotatable bezel, dial, or protractor to measure angles between 0 and 360 degrees, a full circle, mounted on a clear, transparent, plastic, rectangular, base plate. a) Typically the angles are identified numerically every 20 degrees with the intervening angle divided by short lines (or ticks) into two degree increments. b) North (N) is 0 degrees and after completing a full circle, it is 360 degrees. c) East (E) is 90 degrees. South (S) is 180 degrees. West (W) is 270 degrees. These, along with north, are the Cardinal directions. d) The angular degrees increase in magnitude in a clockwise direction when facing the compass from above. 2) A "Read Bearing Here” or “Direction of Travel” arrow on the clear, transparent, plastic, rectangular, base plate. 3) Straight edge. 4) A ruler for measuring inches and millimeters. 5) A housing or capsule, filled with a liquid, for immersion of the needle, to dampen its oscillations. 6) A mirror to aid in accurately obtaining a field bearing. 7) A means of compensating for declination (variation). For purposes of this discussion it should be assumed that the compass, being used, is uncompensated. 8) Magnets for compensating deviation, (error due to the presence of ferrous materials), normally used only in compasses for automobiles, airplanes, and ships. 9) Illuminated or luminous dial for taking readings at night. Note: It is recommended, as a minimum, that a compass with the first five capabilities be used. D) Compass Cautions: 1) A compass needle is a small magnet therefore it is attracted by, other magnets, ferrous materials such as iron and steel, electrical currents that produce magnetic fields, and sometimes deposits of iron ore in the earth. Beware of automobiles, belt buckles, power lines, iron bolts in picnic tables, nails, spikes, axes, knives, steel toed shoes, and metal fence posts.

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2) When taking a measurement or bearing with a compass, the compass must be held flat, level, horizontal and with the axis of the needle vertical. This allows the magnetized needle to freely pivot in response to the earth’s magnetic field. E) What is a Bearing? A bearing is the angular measurement between the direction of north (either true or magnetic) and the direction of some distant object, obtained at the position where the measurement is being taken. The units of angular measurement are degrees between 0 and 360. The angular degrees increase in magnitude in a clockwise direction when facing the compass from above. A bearing is to a compass as distance is to a ruler or odometer. F) What information can be obtained from a map? 1) Description Name of area and where it is located; names of neighboring maps 2) Detail Surface features identified by symbol 3) Direction The top of most maps is north. 4) Distance A scale for converting the distance on a map to the distance on the ground. 5) Designation Natural and man-made features. G) What information is contained on a topographical map? 1) Scale: a) 15 minute series - Scale 1:62,500 or one inch equals about one mile. Quadrangle covers about 13 X 17 miles. b) 7 1/2 minute series — Scale 1:24,000 or one inch equals 2000 feet. Quadrangle covers about 6 1/2 X 8 1/2 miles. Each 7 1/2 minute quadrangle covers about 1/4 the area of a 15 minute quadrangle. c) A minute in geographic or topographic terms is 1/60 of a degree. One degree or 60 minutes equals about 70 miles in longitude and latitude at the equator. Each minute is in turn divided into 60 seconds. In ancient times, minutes and seconds that defined direction and location on earth had some relationship to minutes and seconds that defined time, however inaccurate the relationship was. In these modern times, the only relationship is the same name. 2) Symbols: There is a huge number of symbols that represent different types of natural and man-made features. Some of these are shown in the references. 3) Colors: a) Green: Woodlands, shrubs, orchards, and vegetation b) Brown: Land features and contour lines c) Black: Man-made structures, place names, and boundaries d) Blue: Water, lakes, rivers, streams, oceans, permanent snow and ice, marshes, swamps e) Red: Major highways and land survey lines f) White: No trees, above the timber line g) Purple: Revisions since the previous issue 4) Contour Lines: A thin brown line connecting all points of equal elevation above a datum reference, usually mean sea level. Every fifth line is printed slightly wider, with the elevation printed in brown somewhere along the line. On any given map, the elevation difference between any two adjacent contour lines is identical and stated on the map. This elevation difference is called the contour interval. The elevation difference between two adjacent lines on one Elementary Map and Compass

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map may not be the same as the elevation difference between two adjacent lines on another map. Mountainous areas have larger elevation differences than plains areas. 5) Location: The degrees of longitude (meridians) and latitude that pinpoint the map location on the surface of the earth are identified. Longitude lines, each drawn between the north pole and the south pole, are the lines of constant angular east—west location, measured from the Prime Meridian running through Greenwich, England. Latitude lines are parallel lines, each of constant angular north-south location and are measured north and south of the equator. 6) Place Names: The names of rivers, peaks, valleys, roads, towns, are identified on the map, along with the name of the map and the eight adjoining topographical maps. H) True North versus Magnetic North: A map direction is based on true north. Longitudinal lines on the map point to the true North Pole. The compass needle points in the general direction of the magnetic north pole under the influence of the terrestrial magnetic field of the earth. The magnetic north pole is in northern Canada, near Bathurst Island, approximately 1400 miles south of the true North Pole. The angular difference between true north and magnetic north is called declination (or variation). Declination is not constant throughout the earth. In the United States, the needle declines from 21 degrees west of true north in Maine to 35 degrees east of true north in Alaska. In addition, at any given location, declination changes each year, but this change is so slight as to be meaningless for backpacking purposes, provided a current map is being used. In Maine the magnetized needle points 21 degrees west of true north. In northeastern Alaska the compass needle points 35 degrees east of true north. The area of the country where the needle points directly toward true north includes Wisconsin, Illinois, Indiana, Kentucky, Tennessee, Alabama, and Florida. No compensation for declination is required in these states. At Philmont Scout Ranch in New Mexico and on the Big Island of Hawaii the magnetized needle points 11 degrees east of true north. In Southern California and in the Aleutian Islands of Alaska, the needle points approximately 15 degrees east of true north. The declination is stated on each topographical map in the bottom margin. On older topographical maps a small angle is shown that identifies the grid or map north, the direction of the north star, and magnetic north. On newer topographical maps the declination is stated in a note. In order to accurately use a map in conjunction with a compass in is necessary to compensate in some way for the angular difference between true north and magnetic north. One method of compensation for declination is described below. There are several others. I) Compass Orientation Orienting a compass means to position the compass so that zero degrees (or 360 degrees or N) on the bezel points toward true north. This can be done in the following manner: 1) Hold the compass in front of you with the zero degree indicator directly opposite your body. Ignore the "Direction of Travel" arrow for this demonstration. 2) While holding the compass in this position, rotate your body until the compass needle is opposite the degrees associated with magnetic north (in Southern California this is approximately 15 degrees east of true north). 3) You and your compass are now correctly oriented with true north.

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J) Map Orientation: Orientating a map means; to adjust the map position so that it accurately represents the position of the actual landscape features. This is analogous to holding a photograph of a person, standing in an upright position, so that the person’s head is toward the top of the photograph and his feet are toward the bottom. The map is oriented so that it is easier to understand where you are located on the face of the earth. There are two basic ways to orient a map. 1) With a compass (uncompensated for declination) of the type used in the Boy Scouts, a map can easily be oriented as follows: a) First, align the zero degrees (360 degrees or N) of the bezel with the “Direction of Travel" arrow on the clear plastic base. Note: The “Direction of Travel” arrow and the long edge of the compass base plate are manufactured parallel to each other, therefore after completing step "J) 1) a)” above, both can be placed parallel to a line between zero degrees (360 degrees or N) and 180 degrees (or S), a North—South line. b) Second, place the long edge of the compass base along a north—south longitude line on the map, with the arrow pointing toward the top of the map. c) Third, rotate the map and compass together until the compass needle is opposite the degrees associated with magnetic north (in Southern California, this is approximately 15 degrees east of true north). The map is now correctly oriented. Caution: This compass method assumes that the map is being oriented in the actual location that it represents. If it is being oriented in some other area with significantly different declination, the local declination needs to be used. 2) A second way to orient a map is to select two or more recognizable and visible features and rotate the map until two features on the map are in line with the actual two features on the earth’s surface. K) Determining a Bearing to a Distant Landmark: The bearing of a distant landmark from your present location can be obtained by following, in order, the steps listed below. This is for a compass that has not been compensated for declination. A map is not required to take this bearing. 1) Stand with your body directly facing the distant landmark. 2) Hold the compass flat, level, and horizontal. Point the “Direction of Travel” arrow toward the distant landmark. 3) With the arrow maintained in its position, pointing toward the distant landmark, rotate the bezel until the degrees of declination are opposite the north end of the magnetized needle. (In Southern California this is approximately 15 degrees east of true north) 4) Read the bearing on the bezel where the “Direction of Travel” arrow intersects the angular degree marking. This is the true bearing from where you are standing (present location) to the distant landmark and does not require further compensation for declination.

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L) Plotting a Bearing on a Map with Protractor: A bearing on a map can be obtained between two locations with the aid of a protractor and a straight edge. A compass is not required to obtain this bearing although it is slightly easier with a compass, especially in the field. 1) Draw a true north—south line through the first (present) location. Draw a second line through the first (present) location and the second location (distant landmark). 2) Measure the angular degrees between the true north-south line and the line drawn through the present location and the distant landmark. Remember that north is always zero degrees and the degrees increase in a clockwise direction. The angle measured is the true bearing and requires no further compensation for declination. M) Plotting a Bearing on a Map with Compass: A bearing on a map can be obtained between two locations with the aid of a compass. It is not necessary to be able to see either of the two locations when obtaining this bearing. 1) Find the first (present) location on the map and mark it. 2) Find the second location (distant landmark) on the map and mark it. 3) Draw a line between the two locations. 4) With the map oriented by the compass method described previously, set the pivot point of the needle above the present location on the map with the “Direction of Travel” arrow pointing toward the distant landmark on the map. The center line of the compass will be directly aligned with the line that was just drawn. 5) Rotate the bezel until the degrees of declination are opposite the north end of the magnetized needle (in Southern California this is approximately 15 degrees east of true north). The map is now correctly oriented with no further compensation for declination required. Caution: See caution under compass method of Map Orientation. N) Determination of Position: With the map correctly oriented, you may be able to locate your position by observation of nearby features. If not possible by observation, identify two prominent features printed on the map. Obtain a compass bearing on each of the two prominent features. With the angles obtained, draw a line through each feature on the map. The point of intersection of these two lines is your position. Use features which are as close to 90 degrees apart as possible. 0) Altimeters: Altimeter add an interesting third dimension to a backpacking trip. Topographical maps are two dimensional but illustrate elevation. By knowing altitude, another check on location can be made. Because altimeters measure atmospheric pressure they are subject to errors due to changes in weather conditions and must be adjusted frequently. Altimeters should not be used exclusively, without the benefit of map and compass.

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Bibliography: 1) 2) 3) 4) 5) 6)

The Boy Scout Handbook, 10th Edition Chapter 8, Finding Your Way, Page 179. Fieldbook, Boy Scouts of America, 3rd Edition Chapter 3, Backcountry Navigation, Page 21. Orienteering Merit Badge Book, 1992 Revision, Boy Scouts of America Backpacking Merit Badge Book, 1983 Revision, Boy Scouts of America, Finding Your Way, Page 47. Venture Orienteering Book, 1997, Boy Scouts of America The Official Patrol Leader Handbook, 1988, Boy Scouts of America, Compass Games, Page 76—77, 104— 105, 157—161 7) Cub Scout Academics, Geography, 1994, Boy Scouts of America 8) The Basic Essentials of Map and Compass, by Cliff Jacobson, 2nd Edition, 1997, ICS Books, Inc. 9) Be Expert With Map and Compass, The Complete Orienteering Handbook, by Bjorn Kjellstrom, 1994, Collier Books, Macmillan Publishing Company, (contains an excellent chapter on orienteering plus several map and compass games for easy and fun learning) 10) The Circumnavigators, by Derek Wilson, 1989, M. Evans and Company, Inc. (a great dissertation on the difficulties of long distance navigation) 11) Compass and Map Navigator, The Complete Guide to Staying Found, by Michael Hodgson, 1997, The Bruton Company and ICS Books, Inc. 12) De Magnete, by William Gilbert, 1600, Translated in 1893 by P. Fleury Mottelay, Dover Publications, 1958 (William Gilbert is the early discoverer of the earth’s magnetic properties) 13) Early Sea Charts, by Robert Putman, 1983, Abbeville Press (an interesting history of early maps) 14) The Essential Wilderness Navigator, by David Seidman,1995, Ragged Mountain Press 15) Finding Your Way in the Outdoors, by Robert L. Mooers, Jr., 1990, Popular Science Books (excellent practical information) 16) The Green Beret’s Compass Course, by Don Paul, 1991, Path Finder Publications 17) Land Navigation Handbook, by W. S. Kals, 1983, The Sierra Club (very easy to read ) 18) Lost in the Woods, by Colleen Politano, ICS Books, Inc., Merrillville, Indiana (How to teach a youth, of any age, what to do when lost) 19) The Map Catalog, Joel Makower, Editor, 1986, A Tilden Press Book. Vintage Books, A Division of Random House 20) Map, Compass and Campfire, by Donald E. Ratliff, 1992, Binford & Mort Publishing 21) The Mapmakers, by John Noble Wilford, 1981, Alfred A. Knopf (a great history book on map making) 22) Maps and Compasses, Second Edition, by Percy W. Blandford, 1992, Tab Books, (A long time Boy Scout) 23) Orienteering and Map Games for Teachers, by Mary E. Garrett, 1996, United States Orienteering Federation 24) The Outward Bound Map and Compass Handbook, by Glenn Randall, 1998, The Lyons Press 25) Staying Found, 2nd Edition, by June Fleming, The Mountaineers 26) GPS Made Easy, by Lawrence Letham, The Mountaineers 27) Kiwisport Orienteering, Coaching Manual, A Hillary Commission Programme, New Zealand Orienteering Federation, 1990 28) The Orange County Council Basic Backpack Awareness Training Course presented by The Orange County Council High Adventure Team in the fall and spring of each year. 29) Los Angeles Orienteering Club, c/a Joel Thomson, 5131 W. 134th Place, Hawthorne, CA 90250—5621, 310—978—4595 30) Allied Services, 966 North Main Street, Orange, Ca. 92667 (They advertise that they stock over 250,000 topographical maps from every state in the union) 31) Finding Your Way in The Wild, by Kenton Jones, 1990, (35 minute video), Quality Video, Inc. 32) January 1999 Leadership Training Conference, Orange County Council, Charles L. Hand 32) http://maping.usgs.gov

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