Monster Media 1994 #1/monster.zip/monster/EDUCATE/COMPASS4.ZIP/COMPASS.103

Text File | 1994-01-03 | 170KB | 3,728 lines

 Date: 01-01-94 (15:49)             Number: 2509          Message    9 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
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 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
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                  *****************************
                 *                             *
                *   EMPLOYING MAP AND COMPASS   *
                 *          Ver. 4.0           *
                  *                           *
                   ***************************

                *********************************
                *    By Tom DeLuca, Pack 400    *
                *   All Rights  Reserved 1993   *
                *   Created For Non-Profit -    *
                *    BSA Classroom Use Only     *
                *********************************

"When  you  have worn out your shoes,  the strength of  the  shoe
leather  will have passed into the fiber of your body.  I measure
your health by the number of shoes,  hats,  and clothes you  have
worn out.  He is the richest man who pays the largest debt to his
shoemaker..." Ralph Waldo Emerson




The purpose of this training:  As a result of this course,   each
participant should be able to determine their own ground location
on a Map, and demonstrate Map & Compass techniques.

Needed supplies:  Topographical Map of area,  Needle Map Compass,
Paper, Pencil, and Scientific Calculator.




INTRODUCTION
Everybody who goes out into a wilderness area, especially if they
have  never  been  there before,  whether  just  simply  fishing,
boating,  hiking for the day, or actually camping, needs to carry
on their person:

                             Water
             Small  First  Aid  Kit (Snake Bite Kit)
                    Sun-Screen (Sunglasses)
                            Whistle
                         Pocket  Knife
                      Waterproof  Matches
                         Space Blanket

                      and a Map & Compass.


When  traveling in wilderness that you have never seen before,  a
map, without  knowing where north is...  is just about worthless.
How  are  we going to orient our maps in low visibility  rain  or
fog without a compass?  (There are however many Boy Scout ways of
finding north as we will see...)


On the other side of the coin,  a Compass, all by itself, without
a Map, is also totally useless. Sure, we can find north, but what
good  is that information, if we have no specific destination, or
landmark  to   aim for?   Just walking north may send you  deeper
into the woods. While your are lost, you could use the compass to
scout around the area safely.  However, if you do not even have a
"map"  in  the mind,  the simple idea  where  you're  going,  the
knowledge of north is not going to be much good.

A  Map & Compass work together to form a single Vital  Tool,  for
guiding anyone through the backcountry, through any situation, or
weather condition.

The  trained Men and Women of our Mountain Search & Rescue  Teams
are  the  ones called in from their regular jobs and volunteer to
find  lost  victims.  They  say that  the  rescues  of  literally
thousands of hikers,  campers,  and hunters, which lose their way
in  our  National Wilderness areas every year,  could  have  been
avoided  if these people had only used a map  and  compass.  They
say  that  many of the people that do  carry  them,  don't   even
know how to use them properly.    A great  number  of these  lost
people end up being experienced  Outdoorsmen who were to involved
with  looking around, and just forgot to  pay  attention
to where they were.

In our country, the funds used to mount a rescue operation, is so
large,  that  some  counties  are just not equipped to  meet  the
financial drain.  In parts of the United States,  rescued  people
have been made to pay for their own air-ground search operations.

So far in our local San Bernardino mountains,the cost of mounting
a  search  operation is charged back to the county to  which  the
lost person lives.

Maps are a highly reduced written representation of the ground as
seen  from the air.  They magically allow us to transport a small
portion  of  the world around in our pockets.  With all  a  map's
pretty colors,  lines,   and patterns, it's important to remember
that there isn't a single dot, dash, or line drawn on it just  to
make it  more appealing to the eye. Even the single dash/space in
the twisting line of a foot trail represents 120 feet.

Take   your  time.  They  take some  careful  field  observation,
thought,  and  study,  to see all the information  they  present.
Look  at as many different maps of the area that you can get your
hands on...   before you step one foot  into wilderness.  By  the
time   you find yourself  "lost,"  it  maybe already too late  to
use your map & compass.  Fear can set in, and hamper your ability
to think properly.  At all  times, without exception,  plot  your
course,   and  fix your position  with  a pencil. Even if you are
traveling  with  very  experienced  people,  don't  just  blindly
follow  where they  lead.  They can  become dehydrated,  injured,
or turned around, and maybe just have not discovered it yet.   It
may be left up to you to come up with a plan of action.  With the
solid understand of map & compass given in this  course,   and  a
little  back  country  common  sense,  navigating   through   any
unfamiliar area should hold no problems for you.

                          ************
                          *   MAPS   *
                          ************

"Cartography,"  is  the modern science of making maps &   charts.
The  actual  name "Chart," comes from the Greek  word  "Chartos,"
meaning  "Leaf or Sheet of Paper," and is usually a map  that  is
used  by sailors,   aviators,  and astronomers.  The name  "Map,"
comes  from   the   Latin   word  "Mappa,"  meaning  "Napkin   or
Cloth,"  and usually refers to a chart of the land.

TYPES OF MAPS.
`Atlas' are a collection of Maps bound into a book.
`City  Maps'  are  called `Planimetric Maps'  showing  roads  and
     freeways.
`Land Use Maps' are used in agriculture and soil conservation.
`Cadastral  Surveys'  define  boundaries  of tracts of  land  for
     real  estate ownership and tax purposes.
`Soil Maps' are Aerial Maps used for planning highways.
`Population Maps' show where people are concentrated.
`Rainfall Maps' show the annual precipitation.
`Globes' show a planet as a whole in a way that a Map can not.
`Relief Maps' have bumps at the higher elevations.
`Political Maps' show different colors for various countries.
`Forest   Service  Maps' show basic features,  mountains,  stream
     names, and jeep roads but are without contour lines.
`Weather Maps' appear in the daily news paper.
`Wind Charts' show the prevailing wind currents and their names.
`Nautical Charts' show the depth of the ocean floor.
`Aeronautical Charts' are used by aviators.
`Star Charts' show nebulae and constellation locations.
`Mineral Maps' show the kinds of ore in the ground.
`Topographic Maps' show the relief of the landscape as lines.

Just to name a few.

Many  maps  are dual purpose,  as they are overlaid with  several
types  of Map information.

Every Pilot,  Sea Captain,  or wilderness Backpacker,  starts and
ends their trek by first defining a course, no matter what method
of  route  finding  is used during the trip.  Plotting  a  course
in  route, always involves dealing with what is presently  around
you here and now,  as well as what is to be coming up in the both
the  near,  and distant future.  The outdoor enthuest must at all
times,   know  his  position  by  checking  his  map  &   compass
frequently. He also needs to be aware of alternate routes, should
danger hamper his progress.

It is to your own best interests,  and for the good of mankind as
a whole, that you come to be comfortable with the world of maps &
compass.






TOPOGRAPHIC MAPS.
The Greeks did much in helping to develop the field of geography,
and  the  derived  word "Topographic," comes from  a  combination
of   2  Greek words.  "Topos," meaning,  "Place," and  "Graphin,"
meaning  to "Write or Draw." Topographic maps,  developed by  the
United  States  Department of the Interior Geologic  Survey  Team
(USGS), are what backpackers use most in wilderness travel.  This
type of map  can give the trained eye a very good idea of the lay
of the land.

The skills of reading a map, begin with first finding the correct
map.   The  TITLE  or name of a map is found in the  upper-right,
and  lower-right corners  of a Topo Map.  It will be named  after
the   most  clearly visible location within it's  boundaries.  It
could be named after a mountain,  a town,  or even a lake, ect...
When  the map is folded for storage,  this name should be allowed
to face out.

The DATE the map was made, is located in the lower-right  corner,
and it references  how far back the map was actually drawn, or at
least  updated.   It  is  very important to  take   note  of  it,
because many maps being sold today have not been updated now  for
over 50 years.  This means all the newer changes in the landscape
will not have been printed on them.  However you can bet that the
map  was probably  correct when it was first surveyed.   Examples
of  some kinds of changes to watch for include:

     Completely new trails & new forks in old ones.
     Newly built man made features, and the removal of old ones.
     A swamp may have been drained, or deepened into a lake.
     Lakes can silt up into marsh.
     Streams can dry up, or be diverted.
     A dirt road may have been made into a highway.
     A forest fire may have ravaged the area,  and foliage hasn't
          grown back yet.

So  be  aware  of the revision dates on maps.  PURPLE  DATES  and
FEATURES  mean  that new information,  gathered  by  aircraft  or
satellite  photographs,  have been added to the map,  but that it
has not been re-surveyed in the field yet.

MAP SCALE.  Since the 1920's, it has been a practice to subdivide
a 360 degree globe,  into Degrees,  Minutes,  and Seconds of Arc.
Each  Degree is broken down into 60 Minutes,  and each Minute  is
broken down into 60 Seconds,   just like a 24 hour clock. A 7-1/2
Minute   Map (or 7'30"),  covers 7.5/60ths  of  1 Degree of  land
area on the real globe.

A 15 Minute Map covers 15/60ths of 1 Degree of area on the globe.
A Four times larger area than the 7'30" maps.

As  the  Earth  turns,  it will take the Sun just 7  and  a  half
minutes,  or 15 minutes,  to sweep over the area covered by these
maps.




LONGITUDE,   (North/South lines),  is also called "Meridian," and
starts  at  0  degs   (The Prime  Meridian)  at   The   Greenwich
(pronounced "Grennitch") Royal Observatory,  near London England,
and  counts  up as it increments west.  On the left side of   the
Map,  a typical west longitude on a 7-1/2  Minute Map  might read
117 deg 37'30" (read 117 Degrees,  37 Minutes,  and 30  Seconds),
and on the right, 117 Deg 30'. So by example...

                         117Degs 37' 30"
                       - 117Degs 30' 00"
                       ------------------
                          0 Degs  7' 30"

That equals 7-1/2 Minutes across.



LATITUDE, (East/West lines), also called "Parallels," starts at 0
Degs at the equator,  and becomes 90 degrees at the  poles.  This
means  there is only 180 individual degrees from South  to North.
However, looking at a silhouette of the planet,  you   would  see
there is actually 360 degrees  in  this direction also.

The typical 7-1/2 Minute  Map might  read  34  Deg 22'30" at  the
top, and 34 Deg 15'  at the bottom. So by example...

                          34Degs 22' 30"
                        - 34Degs 15' 00"
                        -----------------
                           0 Degs 7' 30"

That's also 7-1/2 Minutes.

So  the  area  covered by a 7-1/2  Minute  Map  is  really  7-1/2
Minutes  North   Latitude    by  7-1/2  Minutes  West  Longitude.
(About 8x8 miles.)

By the same token,  the area covered by a 15 Minute Map is really
15  Minutes North Latitude by 15 Minutes West  Longitude.  (About
16x16  miles.)  This is simply what the Maps are called, and  how
they arrived at that distinction.

If  you look at Topo Maps of the U.S.  closely,    which are also
called   "Quads" for short,   you  will notice   that   the  Maps
are not perfectly   rectangular.    In   the  Northern Hemisphere
they are wider at the bottom than they are at the  top...   Get a
ruler  out  and  measure  it...   Hmmm...  Let's    see,    7-1/2
Minutes  Latitude  by 7-1/2 Minutes Longitude...  Sounds  like  a
perfect square...   So   why AREN'T they square?  Well these Maps
are  not simply Maps of a region like a Car Map  is.    These are
actually "Area Maps" that show a "Quadrangle of  land"  as  based
on  USGS  Land  Surveys,  which are in turn based on  Latitude  &
Longitude  lines.    They  are  called "Polyconic   Projections,"
meaning  that  they  are  drawn to  have   every   parallel  line
(Latitude)  equal to those distances on the globe,   sort of what
you   would really see looking down from  space.   The  Longitude
lines  as  they near the poles,   get closer together,   and  you
would expect a "Polyconic" Map to also reflect this. A Map of the
equator  region  will  be  nearly  a  perfect  square.   But   at
Latitudes  above 45 Degs,  Topo Maps grow  taller  and  narrower.
Maps    of    the   far northern  edges of  Alaska   are   nearly
triangular in  shape.  The 1:24,000 Scale  series Topo Maps  will
cover  68  square miles in southern Texas,   but only 49   square
miles along the Canadian Border.

In more than 50% of America,  Latitude & Longitude is also broken
down  into RANGES,  TOWNSHIPS,  and  SECTIONS,  as is seen on all
western QUADRANGLE Maps produced by the  USGS.  This  information
is also conveniently  found  on western FOREST SERVICE MAPS,  and
we  will  be covering this aspect further in a moment.

The  SCALE  of  a map is also explained as a ratio  between   the
distances  on the map,  as compared to the real distances on  the
landscape.  It  is expressed on a Topo Map as a fraction such  as
1:1,000,000  which   means  that 1 UNIT of distance on  the  Map,
equals 1,000,000 UNITS on the earth. If,  for example, 1 inch  on
the  map,  equals 1,000,000 inches on the landscape,  the 1  inch
would equal about 15.7 miles of landscape.

The  most useful maps for wilderness travel are by far the  7-1/2
Minute  USGS Topo Maps,  as the 15 minute maps are  being  phased
out.  The  15  Minute  Map  covers  almost  four times more  area
than  a  7-1/2 Minute  Map does.  But the 7-1/2 Minute Map  shows
much greater detail in the landscape.

A 7.5 Minute Map is  said  to have  a  "larger scale" because  it
has  a  ratio closer to  1:1.  Features of the land on   the  7.5
Minute  Map  (1:24,000),   look   bigger,  than they do on a   15
Minute  Map (1:62,000).  Small scale maps  cover larger areas.  A
globe is a "small scale" map.

Distances  on  most maps are also represented  by  a BAR   SCALE.
It  is found   at   the  bottom-middle  of the Topo Map,   or  in
the "Legends" of most other maps. It can convert inches to miles,
feet,  and   kilometers,   and  the map can  be  easily  Xeroxed,
educed  or blown up, with out any loss of scale.

A   15 Minute Map typically has a scale of  1:62,500,  meaning  1
inch  equals about 1 mile (5280 feet * 12 inches = 63,360  inches
in a mile). The Map covers 14.5x17 miles (not square is it?), and
the "Contour Intervals" are 50 feet apart.

A 7.5 Minute Map typically has a scale of 1:24,000, where 1  inch
equals  about  2,000 feet (.378 miles).  The Map   covers   7x8.5
miles, and the "Contour Intervals" are 40 feet apart.











Other common USGS Map Scales Include...

7.5  Minute Maps have a Scale of 1:24,000,  where 1 inch =  2,000
feet,  and covers 49 sq.   mi.  along the 48 parallel, and 71 sq.
mi. in Texas.

7.5x15  Minute Maps have a Scale of 1:25,000, where 1 inch = 2083
feet,  and covers 100 to 140 sq. mi.

15 Minute Maps have a Scale of 1:62,500,   where 1 inch = 1 mile,
and  covers 197 to 282 sq. mi.

30x60    Minute Maps have a Scale of 1:100,000,    where 1 inch =
1.6 miles,  and covers 1578 to 2167 sq. mi.

1x2   Degree  Maps have a Scale of 1:250,000,   where 1 inch =  4
miles,  and covers 4580 to 8669 sq. mi.

Around the border of the Topo Map, you will find 8 NAMES OF OTHER
MAPS.  These are the names of other Topo Maps that match up,  and
belong  next to this current Map.  If your trail dips off the map
momentarily,   and  returns to the map,  be sure to pick  up  the
neighboring  map  also.  The  little  off  map  hike  may   twist
unexpectedly and take you miles out of your way. You may not know
this until it's too late, when the sun is setting.




GRID  LINES.  Look  around  the edge of the  Topo  Map  for  blue
numbered   indexes,   or TICK MARKS.  These are accompanied  with
numbers  like   3801,    or   445,    having  2  different  sized
characters representing the same  number. They  are  spaced  at a
distance  of 1 Kilometer apart,   and are also  called  "Klicks,"
short for Kilometers.

This  Grid  System is borrowed from another type of  map   called
the 1,000-Meter  Universal Transverse Mercator Map,   or UTM Grid
for  short.   You  will  find this reference  in  the  lower-left
corner  of  the  Topo. A "Mercator  Projection"  was  named after
Gerhardus  Mercator  (Juh-rahr'-duhs  Mur-kay'-tur,   1512-1594),
a Flemish Cartographer,   who first developed  it in 1569.  It is
the flat map of the world,    found in  every school  class room,
which badly distorts Greenland,    Alaska,   and Australia. It is
still  used on just about every modern boat  and   aircraft  that
crosses  the  pacific and Atlantic oceans.  Back in the  days  of
Marco Polo,   Magellen,  Columbus,  and Sir Francis Drake, it was
the only map they had. It is by far the most widely used Nautical
Chart of all time. The Military is  now  using  the Mercator Grid
System   as  it's  Standard Coordinate System,  and since  it  is
already printed on our maps through out the world, it provides us
Another way to locate exact points on the map. The calculation of
Latitude & Longitude into  Degrees,  Minutes,   and  Seconds,  is

·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (15:49)             Number: 2510          Message   10 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)
much harder to do than using the UTM Grid,  and this method   has
become  very popular in Great Britain,  and with our own Search &
Rescue  Teams  here in the United  States.  The  Forest  Service,
being   a   "Land   Management"  organization,  still  uses   the
Quadrangle  coordinate  system however.

GRID   COORDINATES are places where the Horizontal and   Vertical
Grid  lines  cross.

Between  each Tick Mark,   each  Kilometer  is subdivided into 10
more subsections, having 100 meters each. So a "Grid  coordinate"
number will have the main coordinate, of say 57 kilometers   from
a Latitude or Longitude line, and  will also state  the number of
10th's  within  that kilometer.  Say 57.3 for  example,  so  your
coordinate  would  be  573.  If you get within 100   meters  from
someone  on  the ground, you're close enough to yell for them.

Look  for  the "Hard Corner" of your 7.5 Topo map.  This  is  the
corner  where both the latitude and longitude lines are marked as
ending  in  30"  seconds. This would be the center of a 15 minute
map  of  the  same area.  There is only one Hard Corner  per  7.5
minute map.  It can be 1 of any of the four, depending on the map
section you have.  It is an important corner.  There you will see
that the Grid Tick Marks are really way up in the thousands.  The
map  will  read  466000meters  E  longitude  x  3775000meters   N
latitude,  and  they  indicate the number of Meters from a  major
Meridian  or Parallel Line.   Only the larger BOLD numbers on the
map   are  used  for giving Grid  Coordinates,  and  the  smaller
numbers  are left out completely,  so the NAME of the correct map
becomes  part  of  the  coordinate also.

A typical  Grid  Coordinate location  would  look like...

      San Bernardino, 15 minute Quadrangle, UTM  326-301

Meaning  the  location  is on the San  Bernardino  map,  at  West
Longitude  Grid  Tick 32 & 6/10ths Kilometers by  North  Latitude
Grid Tick 30 & 1/10ths Kilometers.  The order of the 2 numbers is
always  "Along the corridor and up (or down) the  stairs,"  (Long
then Lat).

The  DECLINATION CHART is located at the bottom of the Topo  Map.
It shows the different angles between TRUE NORTH, MAGNETIC NORTH,
and GRID NORTH. In map making, it is standard to place True North
at the top of the Map.  But don't assume this. Look  on  the map,
as there will be an arrow to point to  north. Grid  North  as  an
example,   is  not  exactly a  MERIDIAN   LINE,  meaning that  it
does not exactly point to the North   Pole.   It's deviation from
True  North will always be shown on the Declination Chart.   This
chart is a very important part of the Map for anyone using a  Map
& Compass.  You will be getting to know it very well.


TRUE  NORTH is a directional line between any position on  earth,
to  the True North Pole.  All lines of Longitude are  True  North
lines,  and  are  also  called `Meridian Lines.'  True  North  is
usually symbolized by an ARROW WITH A STAR on a Topo Map.

MAGNETIC NORTH is the direction to the Magnetic North Pole. It is
actually  the  southern pole of the earth's  central  magnet,  as
is shown by the north seeking needle of a Compass. (Like magnetic
poles  repel,  while  unlike  poles attract.) Magnetic  North  is
usually symbolized be HALF AN ARROWHEAD on a Topo Map.

GRID NORTH is the north that was established by the vertical grid
lines  during  the  Map making process.  Grid  north  is  usually
symbolized by the letters GN or the letter Y on a Topo Map.

CONTOUR  LINES on a Topo Map are brown.  They join all heights of
the same altitude  together.  The  difference  between  1 contour
line and the next  is  called  the  CONTOUR INTERVAL,   and  this
value is located at the bottom-center of the Topo  Map, under
the BAR SCALE.

Every  5th Contour Line is a darker brown line called the   INDEX
CONTOUR,  and  it has the elevation printed on it.  Each  Contour
Interval may equal 200 (or 250) feet between dark lines.

In  addition,  there  are  brown DASHED CONTOUR LINES  in  placed
between the  normal  Contour Lines in very flat areas.  These are
called   CARRYING CONTOUR LINES,   and they represent  elevations
between very widely spaced  Contour Lines.   For example,   in  a
Desert  area where the land may  gain or lose 50 feet in a  mile,
and  the Contour Interval of the map were 40 feet,  the  Carrying
Contour Lines would represent 20 foot indexing.

When  Contour  lines are widely spaced,  you can expect to find a
gentle slope.    When they are bunched really close together, you
can expect there to be a cliff. As contour lines cross a riverbed
they  look  like  a "V" shape pointing up stream.  When  they  go
around the spur of a mountain they look more "U" shaped and point
down the hill.  Map reading is skill you'll have to develop. Only
by  practicing  it,   will you be able to see the  shape  of  the
landscape, in your minds eye.


TRIGONOMETRIC SURVEY POINTS,  or STATIONS,  are very   accurately
surveyed  places,   marked  on  the Map. They can help give a map
reader  an accurate idea of the  land's actual relief.  There are
"Vertical  Controls,"  and "Horizontal  Controls."

A   permanent "Bench Mark" (BM),   is  a small 6X6 inch  concrete
pillar   with  a  brass  USGS  disk  marker  called  a  "tablet,"
physically  placed in the ground,  usually at  mountain  summits,
but  also  in the flat areas around the city.  These  are  called
Monuments  or Stations.   On the BM's face is inscribed the exact
elevation above  sea  level,  and  the  latitude and longitude of
the  marker.   They can  be  a Vertical  Control,  a   Horizontal
Control,  or both.

These  BM  Monuments  are  used as the  corners  of  much  larger
triangles.  The Geological Survey Department them for calculating
altitudes and  distances  around the local  area,  using  angular
measurement (Trigonometry & Geometry), for the exact placement of
buildings and bridges, to follow design engineering diagrams.






There  are many kinds of  surveys.  Surveys  of  water are called
Hydrographic Surveys.  Surveys  for roads  or pipelines are Route
Surveys.   Surveys of the  land  for property lines are Cadastral
Surveys.  Surveys that set the wooden steaks  in  the ground at a
construction  sites  are  Construction Surveys used  in  building
bridges,  mining tunnels, and buildings, don't remove them from a
construction site.

VERTICAL CONTROLS,  can be found anywhere,  in walls, gate posts,
sides of buildings,  sides of trees.  They show the height  above
average  sea  level which has been figured out  very  accurately.
Permeant   BM   Monuments    are  marked on the map  as   "BM   x
with  elevation."   Recoverable markers  (typically  red  plastic
surveyors tape  nailed   in  place)  are  marked on  the  map  as
"x  with elevation."

HORIZONTAL  CONTROLS,  usually  appear only on maps along  roads,
near sea  level,  and  in deserts,   to better aid the map reader
on  very  large flat areas  of land,   where  the contour   lines
are naturally widely spaced.  They can be monuments, recoverable,
or  not  marked on the ground at all.   They are  however  always
marked  on the map  with  an  "Triangle with elevation," or   "BM
Triangle  with elevation" for permeant Monument markers.


QUADRANGLE    markings,   also  called "Cadastral  (ke-das'-tral)
Coordinates"   or "Legal  Descriptions," show up across the  face
of  the  Topo  Map as  very  light red lines  and  numbers.   The
squares  are  in  groups of 36 blocks,   called  Townships,   and
are  repeated  over and over  again across the face of the   map,
and is super  imposed over the map's regular Contour  Line  data.
These  are  PUBLIC  LAND   SURVEY  (USPLS)   area   measurements,
and   are  public records used to record  the   value,    extent,
and ownership  of land,  as a basis for taxation.  The   location
of your map's QUADRANGLE within  the  state,    is located at the
bottom  of the Topo Map.

In  1785,  the  system called the "Land Ordinance"  was  created.
Thomas   Jefferson  saw  that the  migration  west,  needed  some
orderly way to transfer blocks of homestead land to the settlers,
without leaving unused slivers of land left over.

Each red outlined  box, with it's associated number, is 1 SECTION
OF LAND, and it equals 1 square mile (or 640 acres).  They do not
show  up  over  some Federally Owned  lands,  Indian  Reservation
property, Hawaii, Kentucky, Maine, Texas, Vermont, West Virginia,
or District of Columbia, or the 13 original states.

Each  area  of  6  x 6 `Sections Of Land' is equal to 36   square
miles,  and is called 1 TOWNSHIP.

A   RANGE  is  a vertical row of Townships,    numbered East  and
West  from a survey Base Line, and is numbered along both the top
and  bottom margins of the Topo, and the Forest Service Maps.




BASE   LINES  are  not true Longitude or  Latitude   Lines,   and
have  nothing to do with them at all.  In  many places Base Lines
do  not  even  line  up  with   true  north.  They  tend  to   be
North/South,   or East/West  bearings to the highest spots in the
area.  In  the different  states,  or even different parts of the
same  state,   the  centers from which surveyors make Base  Lines
from,   can be different.  The Base Line centers in the past have
been  anything  from mountain peaks,  to city capitol  buildings.
Between  the  Base  Lines,   where  the  Ranges,  Townships,  and
Sections have fanned out  and  now  meet,    there  is usually an
uneven meshing of the Township lines at state lines,   rivers, or
at other borders.

This is a purely Unites States System, and not a Global system as
the Mercator Grid is.

Ranges  are numbered along the top and bottom margins of  a  map.
Townships   are numbered along the left and  right margins.  This
yet  another  way to find a Map coordinate  location.  A  typical
coordinate will look like...

        Angeles Forest R.13W, T.3N, S.22, NE-1/4, NE-1/4.

This translates to:
     On the Angeles Forest map,
     Range 13 West of the Survey   Base  Line,
     Township  3  North of the Survey Base line,
     Section Of Land # 22,
     Northeast   1/4 corner of that section,
     and the  Northeast  1/4 corner,   of   that corner,  of that
          Section (ie.  1/16th of that Section #22, = 40 acres).

Many  "Rock Hounds" (People that collect rocks  for   a   hobby,)
find their mineral  locations  using  this system.

                                  R.13W
        .------------------------------------------------------.
        |          |          |    |  |__|          |          |
        |          |          |    |     |          |          |
        |    20    |    21    |  22 -----|    23    |    24    |
        |          |          |          |          |          |
T.3N    |------------------------------------------------------|
        |          |          |          |          |          |
        |          |          |          |          |          |
        |    29    |    28    |    27    |    26    |    25    |
        |          |          |          |          |          |
        `------------------------------------------------------'

Grid Coordinates vs. Quadrangles.
Ranges,  Townships, and Sections MATCH EXACTLY the Forest Service
Maps  covering  the same area.  Every Ranger has access  to  this
information,  on both their standard Maps,  and on their computer
software.  To  the leader of a lost or injured person,  over  the
phone,  it is the most convenient way to tell the FOREST  SERVICE
where to start  looking.



For  Sheriff  Mountain Search & Rescue  Teams,  Grid  Coordinates
should be used, as the Quadrangles are not used at all.

When  the "runners" are on the phone,  Rescue is going to ask for
some coordinates.  Figure them out before hand,  and write either
the Quad range/township/section,  or Grid Coordinates on the back
of the map.

Neither service  uses Latitude & Longitude for map coordinates.

On your part, it takes several calculations to get down  to
Degrees,  Minutes, and Seconds, and mistakes can be hazardous  to
the victim. Plus,  Dispatch has to convert Latitude and Longitude
back  over  to Quadrangle or Grid,  before he can quickly make  a
computer  print  out  of  that  specific  area  to  give  to  the
helicopter pilot.

Emergency   Procedures...   To be put on back of extra map to  be
     given  to  person running   for  help.   (Put info on a card
     and  keep in first aid kit along with numbers  of your local
     Sheriff's Department.
          Date/Time of accident...
          Subject's (person) name... Sex...
          Description of injury or illness...
          Exact  location of evacuee...    Marked with a X on the
              map to  be given to rescuers.
          What  is wrong... give the details is  victim
              pale/flush, what is pulse rate, respiration rate,
              is he conscious or not.
          Number of members in your party...
          Party location and condition...
          Type of evacuation support requested, when, and
              where...
          Needed extra medical equipment or personnel requested..
          Details    of    evacuation  plan.   Course  chosen  by
              the  main evacuation  party, including  litter
              route, helicopter landing  site, with dates for
              each day of the evacuation...
          Address  ALL  compass  bearings  as  either  Magnetic
              North (MN), or True North (TN). (234 Deg TN or 90
              Deg MN)...
          Site for runners and main party to reconvene and
              dates...
          Details of contingency routes...
          Signature of group leader and other witnesses...

The real advantage to knowing about Quadrangle sections,  is that
the Map is already marked off in mile squares when  you  buy  it.
The trained eye,  at a  quick  glance, can immediately tell about
how   many miles to go to reach the destination without the  need
to measure.







THE 7 COLORS OF A TOPO MAP
BLACK  - Cultural Man Made Objects - such as  Campgrounds,  Bench
     Marks,  Roads,  Buildings,  Water Tanks,  Schools, Churches,
     Mines,   Dams,  Railroad Tracks, Power Lines, Trails, Names,
     Boundaries as County,  State,  Forest Service  District,  or
     National Forest.

BLUE  - Hydrographic  Features (water)  - Names,  Oceans,  Lakes,
     Glaciers,  Swamps,   Springs,  Dry Lakes,  Seasonal Streams.

BROWN  - Contour Lines,  Carry Contour Lines,  Depressions,  Peak
     Elevations, Earth Levees, Sand Wash, Gravel Morain.

GREEN - Vegetation - Mangroves,  Solid For Woods,  dotted pattern
     for chaparral, Orchards, Vineyards, or Woodland Swamp.

RED - Primary Highways,  Roads Under Construction,  Bridges, Land
     Survey Corners, lines.

WHITE - No Vegetation - Surface Grassy, Sandy, Rocky.

PURPLE  - Features  Added From  Aerial  Photographic  Information
     During Map Revision, Not Yet Checked In The Field.

TOPO SYMBOLS.
Symbols can either be directly representational, or  an icon, and
are   printed  in  colors  consistent  with  what  they  mean.  A
copy of the Department  Of  The Interior's pamphlet  "Topographic
Map  Symbols" is free at any location that sells Topo Maps  (3$),
and  it  describes all the symbols found  on Topo Maps.  The  Boy
Scout Handbook, and the Fieldbook, also  covers symbols.

Topo   Maps also show Man Made Features.   But beware,  man  made
things  can appear and disappear over night.  So don't  place too
much reliance on them.   Learn to read the shape of the land,  as
the land  surface will almost never  change.

HOW TO FOLD A TOPO MAP.
Topo  maps  are not folded when you buy them.  They  usually  get
rolled  up instead.  On the trail,  it is normal to fold the  Map
"anyway  you  have to" in order to see on it,  the area  you  are
walking in.

However at home, for the ease of locating the correct
Map from a larger pile, it is best to fold a Topo Map like a "W".
That  is first,  in the vertical direction fold it face to  face,
folding  the Map in half.  Then fold back the outer edges so that
the  Map's  name shows in the upper-right  corner.  Then  in  the
horizontal  direction,  fold the Map in half,  and then fold  the
upper and lower portions back,  so that the name still shows.  In
this  way  you  will be able to locate a  specific  Map   without
having to open every one to see the name each time.






HOW TO PROTECT MAP FROM THE WEATHER.
If you carry a plane paper Map into the wilderness, you will need
to   protect  it  against the  elements.  Against  over  folding,
against  jelly & peanut butter sandwiches,  and against  it  just
plain wearing out.  If it gets rained on,  it could tear,  and be
next  to  useless in helping you find your way.  There are  clear
plastic Zip  Lock Map Pockets,  sold on the market,  that let you
refold the Map,  and stuff it inside so that the area you will be
walking  shows through.  The 2 gallon 'Zip-Loc Freezer Bags`  can
also be used. There is also a product called 'Aqua  Map Seal` for
permeant  water  treatment,  that  also  prevents  the  map  from
fraying,  as  it allows you to fold and  unfold  indefinitely.  A
single  8  fluid  ounce  bottle  treats  about  15  Maps,   ($6).
'Thompson's Water` Seal is another method.   And a product called
'Clear Seal` for basements is another product to try.

"I  went to the woods because I wished to live deliberately,   to
front only the essential  facts of life,   and see if I could not
learn  what  it  had to  teach,  and not,  when I  came  to  die,
discover that I had not lived..." Thoreau.

                    ************************
                    *   Magnetic Compass   *
                    ************************

HISTORY OF THE COMPASS.
All  official badges of the Boy Scouts  of  America,   are issued
by the National Council in Irving Texas,  under the Authority  of
Charter of the US Congress. They can only be worn by BSA members.

They are protected,  (as is the uniform,) by U.S. Letters  Patent
41512 and 41532, and anyone infringing upon them   is   open   to
prosecution.  The  Boy  Scouts of America reserves the  right  to
recall for cause,  at any time,  any badge awarded.

While the Scouting Symbol itself may look like the French "Fleur-
de-lis,"  it was really  the True North symbol as taken from  the
Mariner's  Compass face.    The Compass was,  and  still  is,  an
extremely  vital tool for  navigation.

It  has  been  said that the  Chinese knew  about  the  "magical"
magnetic   properties  of the iron mineral ore called  lodestone,
way  back  as early as 2634 B.C,   over 4,500 years ago.

At that time,  they had no idea that while the iron ore was still
hot  volcanic  magma,  it's  atoms had aligned with  the  earth's
magnetic  field,  and  as  it cooled  back  to  rock,  it  became
magnetized.

·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (15:49)             Number: 2511          Message   11 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)

The   ancient    Greeks  also  knew  about  the  weak  attraction
lodestone  had  to tin,  but the  compass's first  actual use  to
get bearings at sea,  is placed closer to around 300 A.D.,  about
1,500  years ago.   Chinese sailors were reported to be using  it
around 1100  A.D.   Arabian merchants  had  started  using  it by
1220   A.D.,  and  the Scandinavian Vikings  by  1250 A.D.. Marco
Polo  brought Europe's first  compass back from the Chinese  city
of Cathay at the  close of the 1200's,  around the time  of Robin
Hood.

In  the early days of the compass,  it was only a small piece  of
rock ore,   strapped to a small floating piece of wood.  It could
even be hung by a   thread.

The   things  that  the early navigators enjoyed most  about  the
magnetic  Compass,   was that it was very easy to  use.  It  made
steering   a ship much more accurate.  And it could even be  used
when the  skies  were  cloudy,  when the  more  accurate   method
of navigating by the stars was not possible.

In  all  the  past centuries of adventure,  when men  of  courage
sailed  strange & dangerous seas,  and blazed trails  across wild
unsettled  continents,  the direction of North was their one  and
only  fixed  point  on the globe.  This 3  pointed  sign  of  the
compass,  came  to  stand  for the   North  with  the  Explorers,
Pioneers,    Trappers,   Woodsman,   and Army Scouts.   It became
their   emblem,   and has only been slightly changed as centuries
passed by.

Today,  this  same TRUE NORTH symbol has become Scouting  youth's
fixed point.  It guides Scouts of courage,  of all ages,  through
the  unsettled  times  of youth,  across  strange  and  dangerous
situations, and helps the Scout blaze new Morally Straight trails
to freedom, and Truth.

POINTS OF THE COMPASS.
Before  the  Magnetic Compass was discovered,   early map  makers
would draw a small 16 pointed circle on the map, and place an "N"
to  point to North.  These were the 16 Cardinal Points from which
the  winds  were thought to blow. This drawing was called a "Wind
Rose."  When the magnetic compass came along,  it was   naturally
just  usually set on top of the Wind Rose  pattern in  order  to
help  face the sea chart in the proper direction.  The wind  rose
started to become known as a COMPASS ROSE.  (Today it also called
an AZIMUTH RING, or GRADUATED DIAL.)

Since the 1100's,  compass bearings have been split into...

      N,NNE,NE,ENE,E,ESE,SE,SSE,S,SSW,SW,WSW,W,WNW,NW,NNW,N

This   was  all the pinpoint accuracy an old   Mariner's  Compass
had to offer,  and  by  todays  standards,  it  was  not  a  very
accurate. However as global spherical  mathematics
improved,  it   became  more  customary   to   give  bearings  in
units of "Degrees" from  Geographic  North.    In the 1920's,  it
became   an   accepted  world   wide   practice    to    indicate
direction,   called  HEADING,  AZIMUTH  or  BEARING,  by a single
number,  (0-360,) representing  degrees  of  a  circle,    called
"Arc," as measured  clockwise  from True North.

The  development  of  the compass  instrument  itself  represents
scientific achievement, however the actual use of this instrument
is  more of an art form.  Once someone finds a method that  works
for them,  I have found it easier to get someone to change  their
religion,  than to change the way they use a  Map & compass.


The  Compass  is not by any means a  complex  instrument.  Almost
every backpacker carries one,  and it is very surprising just how
few of them are really able to operate it in all, or even most of
it's many uses.  With a positive attitude,  and a determined will
to  understand,  ANYONE from 9 to 90,  is able to  learn  compass
operation  with  just  some practice,  and understanding  a   few
simple principles.  If you are going to carry one,  you should at
all  times (a.) be certain how to work it,   and (b.) unless  you
have  proof that it is malfunctioning, TRUST IT!  Never  look  at
using a  Compass  as something hard to do. It's really easy!

TYPES OF COMPASSES.
The  FIXED DIAL COMPASS  is the typical cheep aluminum  .25  cent
gum  ball  machine,  or plastic "Zipper-Pull" type compass  (6$).
Some  at  first  glance even somewhat  resemble  an  orienteering
compass.  These  have a "Fixed Compass Rose" that does not  move,
that  is  printed on paper,  stuck under  the  Needle  Pivot,  or
melted into the outside plastic housing.   They may or may not be
filled  with liquid.  They  are   marginally better to  use  than
figuring tree ring growth (NNE), or looking at lichens  on  rocks
(South),  but not as good  as  sighting  on Polaris (True North),
or using the sun/stick method (True North).

However  they do not have allot of different uses.  They are  not
very  versatile,  because they can not work as a "Pelorus,"    (a
navigation protractor).  However,  having a Scout carrying one in
his survival "10 Essentials Pack" may still be an excellent  idea
as a back up.  (Play around with magnetizing your 10 Ess.  sewing
needle  at  home,  and  floating it on some toilette paper  as  a
backup compass.)

The FLOATING DIAL or CARD COMPASS is the type most found on board
boats and in  some   cars  under  the front  rear-mirror.   There
are   even  floating  ball key-chain  compasses.   This  type  is
usually mounted,  or gimbaled,   to pitch  and   roll freely,  so
that   ocean   swells will  not effect it's  levelness  with  the
horizon.  They are usually sealed inside a liquid filled chamber,
so it can spin freely.  Old ship's compasses  used gin to  dampen
the  compass  disk,   today Mineral Oil is common.  Many offer  a
setting   screw  to  compensate for  metal   vehicle   dashboards
around  them,   and  thus  Zero them  to  Magnetic  North.  These
compasses  are  read  from behind,   along an indexing   mark  or
line,   as you are facing in the DIRECTION OF TRAVEL. In order to
take a bearing on a lighthouse,  the whole vehicle must be turned
around   and   pointed    at it.   Thus a compass  mounted  in  a
vehicle is not as  convenient as others we will mention.

The  LENSATIC,   or   PRISMATIC  COMPASS is  a   military   type,
folding  Compass.   They   usually have an  aluminum  housing,  a
sighting  wire,   and an eye  piece,  usually made of glass,   to
view the  Compass  Rose when a bearing is  being taken.  Most  of
the  time they employ a "Card" type compass Dial,  and this makes
for single handed operation.  (Any magnetic "needle" type, always
requires   2   hands.)  The Bezel Ring,  attached to  the   glass
face, will click as it turns the Indexing Mark. Each click equals
3  degrees,  for  reading  directions in  the   dark. A direction
of "12 clicks" (from north),   equals 36 degrees,   or 50 clicks,
equals  150 degrees.  The Bezel Ring Indexing Mark can be  "set,"
and  this becomes your Bearing.   A  thumb  loop  helps   to  aim
the compass properly at the end of  the operators  arm.  Some are
housed  in  a "Pill Box" case,  and others many have   a    ruled
straight  edge along their  side.   The   sighting  device,   and
the Card Dial, together form a "Pelorus" protractor necessary for
getting   or  "shooting" a  bearing.   They  are   very  ruggedly
constructed,     and    work    very   well    for    backcountry
navigation.

Any  Magnetic  "Card"  type  compass,  by  it's  very  nature  of
operation,   is a "Magnetic North" type  navigating device.  They
do  not  lend  themselves to  the  "True North"  methods  that  a
magnetic   "needle"  type  compass  will.   Their  operation   is
different,  don't confuse yourself by attempting to learn BOTH at
the same time.

The ORIENTEERING MAP COMPASS is a Swiss design,   first developed
back  in   the  1930's.   They have a flat Base  Plate,   and   a
twistable  Compass  Housing.  These  together  form a   "Pelorus"
protractor necessary  for  plotting a heading.

On  the  Braun (tm.) compass,  the whole Needle Housing moves  to
compensate  for Declination,  and is designed to be  a  "Magnetic
North"  type device.  The Silva Ranger (tm.)  uses  an adjustment
screw  that moves only the internal Orienting  Arrow, and  leaves
the Orienteering Lines alone,  and is both  a  "True North" and a
"Magnetic North" device.  These compasses usually have ruled inch
and millimeter scales on their Base Plate.

On the Base Plate itself is the "Direction of Travel Arrow,"  and
this  can be "set" to the Azimuth Compass dial,  and this becomes
your BEARING.

They  have Mineral Oil filled  Needle   Housings,    with   steel
needles  that pivot on a sapphire bearing. Do not leave a compass
in  the  sun.  The oil vial will  heat up and expand the plastic,
giving the needle room to either fall off the pivot, or even blow
the  face  off the Needle Housing.  At higher altitudes,  an  air
bubble  can  form in the Needle Housing,  but upon  returning  to
lower  elevations  the  bubble  will again  dissipate  back  into
the oil. This is normal, and not a problem unless a bubble larger
than  1/4  inch forms,  and this  should  be suspected as being a
leak in the Housing.  A large air bubble can grab the needle  and
keep it from pointing to Magnetic North.

Both the Lenstatic, and the Orienteering compasses  are very good
pieces of equipment. However it is the considered opinion of BSA,
that  the  Orienteering   Compass is the most  flexible  type  of
compass  for the recreational navigation in the wilderness.

With this type of Compass,  it is possible to determine a Bearing
from a Map (True North),  without always needing to stop and turn
the  Map  North.  Nor is absolutely necessary to   draw  Magnetic
Declination Lines across the face of every  map you own.




Wait  a minute!  Did he say that?...  Yep!  Using an orienteering
compass,  you do not need to orient your map,  or even draw lines
on it.  The compass does all this work for you, automatically, as
we will see...

Orienteering  Compasses may look like a light   weight  toy,  but
make no mistake,  they are a precision piece of gear. Though they
are   a durable and rugged apparatus,  it should be due the  same
respect  given  any  fine instrument. Take care not to throw,  or
drop  it,  or carelessly let it bang around.  They are  wonderful
scientific tools, yet so simple that an 8 year old  can learn how
to use it.




------------------------------------------------------------------------------
 Date: 01-01-94 (15:54)             Number: 2504          Message    4 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
Message-ID: <[e-mail]>
(2/4)
WHAT IS A GOOD BASIC ORIENTEERING COMPASS.

[]  It will have a Steel Magnetic Needle painted Red  for  North,
     that glows in the dark.

[]  It will have a Sapphire Needle Bearing that eliminates errors
     caused by friction of the pivot.

[] It should have a sealed,  liquid filled,  needle  housing,  to
     dampen the swing of the needle in under 4 seconds.

[]  It will have an easy to grip rotating Graduated Dial,  marked
     in  at  least  5 degree or 2 degree increments,  from  0  to
     360 degrees.

[]  It should have a see-through Base Plate with a DIRECTION   OF
     TRAVEL  ARROW on  it  for  sighting  along bearings.


[] It will have an ORIENTING ARROW under the needle for orienting
     to declination.

[]  It  should  have ORIENTING MERIDIAN LINES under  the  Compass
     Needle,  for  orienting  to  True North  or  Magnetic  North
     "Meridian Lines" on the Map.

[] A ruled straight edge on the flat BASE PLATE to convert inches
     into  miles  on a standard Topo  Map,  Millimeter, and  Inch
     scales.

[] Lanyard for carrying around on neck.

Other conveniences include...

[] A Sighting Mirror,  with a Sighting Line, for viewing both the
     distant  landmark, and the Compass Rose bearing  numbers. It
     is used to get a very accurate reading.  (Is also good   for
     shaving  and signal aircraft rescuers.)

[] Built in magnifying lens to see tiny Map names, and altitudes.

[] Inclinometer or Clinometer to measure the steepness of trails,
     to  shoot  angles  to distant peaks  and  help  locate  your
     position.

[]  The more expensive Compasses,  have an Adjustable Declination
     Set  Screw.  This moves the Orienteering  Arrow  inside  the
     Needle  Housing.  Once set,  it takes care of all mathematic
     conversions for  declination,  between Field  Bearings   and
     Map    Bearings,  automatically.  (This  is  the   same   as
     placing  a narrow  piece  of  tape  on  the  Compass housing
     to  be   discussed later. This IS the "True North Method.")

[] Some  have  an Adjustable Needle Housing that twists and   can
     be   reset   within  the  Compass  Rose  to  compensate  for
     declination (Braun).

Every one in the wilderness should have a Map & Compass and  know
exactly how to use it.

DECLINATION.
The  magnetic  field of the Van Allen Belt,  which surrounds  the
Earth,    is not easy to understand.  For one thing it  does  not
run directly through the Earth's center of  gravity.  It  is off-
set  by several thousand miles away from the center  of spin   as
it   runs   under   the   pacific   ocean   to   the     southern
hemisphere.  This   causes  a  different amount of  "dip"  to  be
measured along the  same latitude through out the world.

For another thing,  the Equator, is the only  place on the planet
where the magnetic lines of force are completely  parallel to the
ground.  Every  where  else on  the planet,  the  magnetic  field
points  down into the Earth at an increasingly steep  angle as we
move towards the poles.  This vertical angle  component,  between
the  magnetic  lines of force,  and the flat ground,  is   called
"Magnetic Inclination" or "Dip."

At  latitudes  greater  than 65  degrees  North,  the  horizontal
magnetic  component  of the Earth's field,  needed to  deflect  a
compass,  becomes  too  weak and erratic  for finding directions.
Shipboard   navigators  are  required to  use  non-magnetic  gyro
compasses   (spinning   at  26,000   revolutions   per   minute),
Lorans,  Omegas,  or Celestial Navigation (star charts & Sextant)
to triangulate their positions.

(A Loran is a radio that picks up transmitted timing signals.  It
measures the intervals between 2 incoming signals,  and shows the
distance  to  the beacon stations.  Omegas use frequency    phase
shift   much  the  same   way  as  Loran   uses time  delay,  for
locating a ships position along  well  defined shipping lanes.)

The increasing strength, of the vertical magnetic lines of force,
as  they  converge into the ground at the poles,  are many times
stronger than they are at any other place on the planet.

Compasses  are  manufactured  with the proper amount  of  counter
weighting,  and the proper amount of magnetizing lines permeating
the  needle.   They  are made in close proximity to   the  actual
angles   of  force   it   will   encounter    in    a    specific
continental location in the world.



As  an  example,  as a "made for U.S." compass,  nears  the  pole
region, the magnetic needle will increasingly begin to point into
the earth.   You'll have to hold the compass housing unevenly  to
get  any  kind of reading at all.  All the needle wants to do  is
point into the ground,   and not to the horizon.  Maybe a  Needle
with a weaker magnetic field, or counter weighted differently may
help.  However  there  are  places   on the  globe  where  it  is
impossible  to get  any   reading  at  all,   with  any  kind  of
magnetic  compass,   due  to   this phenomenon of "dip."

So  if you are going to Alaska,  Finland,  or Australia,  be sure
to pick  up  a Compass made for that area,  as your made for U.S.
Compass will prove to be unreliable.

And  finally,  still one other problem with the Earth's  magnetic
field.  One  with which we will have to deal with more  directly.

Only  at 2 North/South lines in the  northern   hemisphere,  does
the  compass  needle point to True North.  One is through  Russia
and  the other is Wisconsin & Alabama in the U.S..  At all  other
places on  the globe,  the  Compass  will either point East,   or
West,   of  the actual  Geographical  True North,   by  an  angle
called  "Magnetic  Variation"  or "Declination." This is the name
given to the  angle,  between  True  North,  and  Magnetic North.
Magnetic   North   is   located   about  1,000  miles  South   of
Geographic   North,   near  Bathurst Island,   centered  off  the
Northern coast of Canada above Hudson Bay.

In  the continental United States,   this angle of error is going
to  be   between  25 Degs East,   to about 23 Degs West  of  True
North. Alaska's  declination  ranges from 15 Degs East to 36 Degs
East.

And to top it all off, these values will slowly change over time,
as   the   earth's continental drift moves the  crust  over  it's
molten  mantle at 2 to 4 inches per year.   Along with  that,  on
June 27th,   1992, the  San  Bernardino  Big  Bear 6.2 earthquake
caused  the   San Bernardino  Mountains  to  jump over the valley
by  1.5  feet  in places.  This  in turn twisted the valley floor
slightly,   and caused  the declination of the valley to actually
gain 1/2 degree in 30 seconds, from 14.75 Degs to 15.25 degrees.

To  find a declination for an area you would wish to  visit,  you
can always call an airport's Flight  Control  Center,  24 hours a
day,  to get a very accurate Declination. Even the best Topo Maps
can be slightly off.

So  what I need you to under stand is when   using   a   Compass,
you   have   to  always  compensate  for declination one  way  or
another.  You  can either draw "Magnetic Lines" on your maps,  or
let the compass correct for Declination for you.







DEVIATION.
A compass can give an incorrect reading if it is in the  presents
of  iron,    steel,    or  the presents of electrical  wires that
makes  a local magnetic field.   These will prevent the   Compass
needle  from correctly pointing to Magnetic North,   and can help
throw   you way  off  course. When finding North, watch  out  for
nails  in  picnic  tables,   Belt   buckles,   Knives,  Lighters,
Karabiners,  and  even red rocks (which happen to contain  iron),
that you may set your compass on.   And forget even trying to use
the compass to orient a Map on the hood of your car.

BEARING, also called Azimuth.
Is a horizontal angle,  that fixes a direction in respect to True
North,  (or Magnetic North), as measured in a clockwise direction
on the Compass Rose.

Some  Compasses use a different system of  direction  expression,
than  Azimuth, found on  your  regular  Camping compasses.

One  of these other types is called the QUADRANT  SCALE  Compass.
The  graduated dial is  still marked off with 360 degrees all the
way  around,   but it is  very different from the normal  Azimuth
Scale you may be  used  to.

The   Quadrant  Scale  system   calls  North - 0   degrees,   and
increases  to  90 degrees  at  West,  then decreases again  to  0
degrees at South,  and then increases to 90 degrees at East,  and
0 degrees at North again.

                   Direction   Azimuth    Quad
                    North       0/360     0/0
                    East          90       90
                    South        180        0
                    West         270       90

Directions are given in quadrants such as "North 20 degrees East"
(Equals  an Azimuth of 20 degrees),  or "North 15  degrees  West"
(Azimuth of 345 degrees),  or "South 40 degrees East" (Azimuth of
140   degrees)  or  "South  10  degrees  West"  (Azimuth  of  190
degrees).  This system is based on Polar Rectangular Coordinates,
for  use  by  Foresters,   Surveyors,  Geologists,  Builders  and
Engineers.


Another  system,  the  METRIC SYSTEM, has it's own version of the
Azimuth  Dial also, and it Breaks  the regular  360  degree dial,
into  400 Grads.  This means that 90 degrees East,  is also equal
to  100  Grads  East,  and South is 200 Grads.  This  is  further
broken  down into Centigrads (1/100th of a Grad),  and Milligrads
(1/1,000th   of a  Grad).   These  are   extremely  fine  angular
measurements,   and  much finer than you need to  bother about in
the field.

                   Direction   Azimuth    Grads
                    North       0/360    0/400
                    East          90      100
                    South        180      200
                    West         270      300

Another    system   is   the  military usage  of  the   MIL.  The
regular   360  Azimuth degree circle,    equals 1,600  mils.   So
East is  represented  by 400 mils,    South is  800 mils.  It  is
used mainly for aiming military Gunnery.

                   Direction   Azimuth     Mils
                    North       0/360    0/1600
                    East          90       400
                    South        180       800
                    West         270      1200


We   have   already   talked  about "clicks."  It  is  a  forward
tactical  military   direction   expression.    90  Degrees  East
Azimuth  equals  30  clicks,  and 180 Degrees Azimuth  equals  60
clicks.

                   Direction   Azimuth   Clicks
                    North       0/360     0/120
                    East          90       30
                    South        180       60
                    West         270       90

It   is  unlikely that you will need to know these other  Azimuth
Markings,  but they do exist, and show up occasionally.

The   type   of graduated dial used by most  Outdoorsman  is  the
AZIMUTH SCALE. A system of 360 degrees.

Just to make you aware,  there are a few types of "bearings," and
is important that you know the difference between them.  Look  at
your  map's Declination Chart.  There are True Bearings (measured
from True North),  Grid Bearings (measured from Grid North),  and
Magnetic    Bearings  (measured  from  Magnetic   North).   These
expressions are  referring to the "Degree of  Angle"  between   a
"Direction  of  Travel,"  and  the angle of  either  Grid  North,
Magnetic North,  or True North. So any Direction can be expressed
as  3  different  bearings,  and still  be  correct.  It  becomes
important  that all bearings be defined as 260GN, 50TN, or 180MN.

In addition, there are Map Bearings, and Field Bearings.

A Map Bearing, is a bearing taken while looking at a Map,  to  be
applied to the land,  and can be expressed as Grid,  Magnetic, or
True North.

A  Field Bearing is taken while looking at the landscape,   to be
applied to  a map,  and can also be expressed as Grid,  Magnetic,
or True North.

In this Syllabus you will be taught  "True Bearings" in  relation
to "True North" only, mostly because maps are True North.





First  the  bad  news...  Using a Compass to locate North in  the
field (Field Bearing), is different than finding North with a Map
(Map  Bearing).  This  is   due   to  the  Magnetic  Declination.
The Map (True North),   and the magnetic needle (Magnetic North),
speak   2  different  languages.

Whatever distance you travel,  for each degree of declination you
don't account for,  you will be off your course 1/60 of the total
distance traveled.

           1 Deg  = 88 feet off course at 1 mile out.
           2 Degs = 176 feet off course at 1 mile out.
           4 Degs = 352 feet off course at 1 mile out.
           8 Degs = 704 feet off course at 1 mile out.
          15 Degs = 1,506 feet off course at 1 mile out.

This means that at 15 degrees declination, at 1 mile out, you can
be  1/4  of  a  mile  off  course.  Just  imagine  how  important
Declination would be in Alaska at 36 degrees...

To  correct  for these differences,  mathematic  conversions  are
necessary.  We need to "add" or "subtract" our local Declination,
to our bearing, every time the Compass is used...

In the  western  United States,   for Map Bearings, to convert to
Field Bearings,  add your local  declination  to get the  correct
Magnetic   Bearings  to  be  applied to  the  land.    For  Field
Bearings,  subtract  your local declination to apply to the  map.
On  the east coast,   the opposite math needs to  be   preformed.
Let's  face  it,   in  the   real  world  of  the wilderness,  it
is NOT EASY to remember when to  add and  when to subtract.

Now  the  good news...  There is  however,  a couple of  ways  to
completely   eliminate    the  mathematical  differences  between
Magnetic  North and True North,  so you never have to think about
them again.

The    "Magnetic  North method" uses a series of  parallel  lines
that  YOU draw  on the  Topo  Map,   parallel to the  Declination
Chart  at the bottom of  the   Map.  These  new  drawn Map  lines
then  represent your new "Magnetic  Meridian  lines" pointing  to
Magnetic North,   so that the Compass needle,   Compass  Housing,
and  the  Map,   all  speak the same language.   From  this  time
forward,   the  Compass is  used  "Magnetic Needle" to  "Magnetic
North on Housing" to "Map Magnetic  North" to   get  a   Bearing,
and   we  can  completely   forget   declination.   All  bearings
are   then  given  as degrees from Magnetic North to your Bearing
or heading. Be sure to mark it MN when you write it down.

"Boxing    the    Compass,"  is the oldest way on the  planet  to
orient a  Map   using   a simple  Fixed  Dial Compass,  having no
Magnetic  Meridian  lines drawn  on  the Map.   The map is placed
on  the  ground,   and  the Compass is placed on the  Declination
Chart.     Together  the Map &  Compass is then turned  until the
needle   completely  covers,  or   "Boxes"   in   the    Magnetic
Declination   arrow   on  the Declination Chart.  The map is  now
oriented   to  the lay of  the land.   This  must be  done  every
time magnetic bearings are to be taken with a simple compass.

Some  of  the  drawbacks  to  the Magnetic  Method,  are that the
Declination   Chart   line  is   only  1  inch  long.   A  slight
misalignment  of  a line  drawn squarely across  the  Map,  could
result in a sizeable error.

Also,  in the cases of very small degrees of declination, be sure
to  take  the  time to MEASURE the exact number  of  degrees  the
Declination Chart  specifies,  before drawing all these lines in.
Sometimes the declination in an area is  small,  and Map   makers
exaggerate  the  visual  Declination  Chart  for  the  sake    of
clarity.  So measure the actual degrees along the  center line of
the map with the Compass Rose before drawing any lines.

Another  problem  is  that a Topo Map is a picture  of  a  Curved
Surface, so straight lines drawn across it may be accurate in one
corner, but off in another. The Navigational Chart for Lake Tahoe
shows  the Magnetic Declination as 15.75 at the southern  end  of
the lake,  and 16.25 at the northern end (in 1960).   I'm talking
about a lake that is only 20 miles long.   That is about the same
area covered by a 15 minute Topo.  So drawing straight lines,  on
a 1x2 degree map,  are going to be way off.

It  occurs  to me that the Magnetic North Method,  without  those
lines,   can't be used very accurately with every  day  car  maps
either.  I need a method I can use with my Topo  maps,  AND every
other map too...

The TRUE NORTH METHOD...
The  other method commonly used,  which does the same job as  the
Magnetic North Method,  is the True North Method.  A  small strip
of  tape,  on  the face of Needle Compass  Rose,  at  the  proper
Declination, can turn your compass into a True North Compass.

Right now,  get up,  and place a 1/8 inch strip of tape from  the
center of your compass,  to the correct degrees of declination in
your  area.  (Riverside,  Calif,  is  15.25 Deg.)  This  will  be
necessary in order to follow along with this instruction.

From this time forward, there are only 2 rules:

-----------------------------------------------------------------
=================================================================

1.  When  taking  Field Bearings...  Put the "Compass Needle"  to
"Tape," - Always!

2.  When  taking Compass Bearings...   Put the  "Housing Meridian
Lines" to the "Longitudinal Meridian lines on the Map," - Always!

=================================================================
-----------------------------------------------------------------

That's it... That's all there is to it...

Read them again...


Now   the  "Compass Rose," "Base Plate," and the "Map," any  map,
all  speak  the same language of True North,  while the  "needle"
still points to MN.  There  is no need to  draw lines on any map,
and the need to "Box the needle" is eliminated.  All bearings are
then  given  as  "True North Bearings," and you  can  forget  the
declination,  because  the  compass   has  included  it  in  it's
measurement.  Be sure to mark it TN when you write it down.

·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (15:54)             Number: 2505          Message    5 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)

HOW TO WALK A BEARING.
Try  this outside.  Pick the Compass up and place in the palm  of
your  hand.  Turn the Azimuth Ring dial to some random number  on
the Compass Rose.  Now holding the Compass chest high in front of
you,  turn  your  body and Compass together as a unit,  until the
Needle  points  to the tape.   Now look out beyond the   compass,
straight   ahead.   The   further  out you can look  beyond  your
destination the  better.     Choose some "landmark" or  "Steering
Spot"  which    is  in  line  with  the direction you   wish   to
travel,  as pointed  to by the "Direction of Travel Arrow" on the
Compass  Base Plate.  You would then put the Compass  away,   and
walk   to   that  landmark,  or  spot,  without looking  at   the
Compass again.    When  you  get there,  then use the Compass  to
locate  the next bearing,  and locate the next landmark, then put
the compass away again.   It is just that easy...   (Note  do not
walk while  staring at the Compass  Needle,   you  might  stumble
over something,    or get bitten by a snake,  or eaten by a bear!
Watch  where  you  are going in  the  wilderness.  Use  "Steering
Marks"!)

Here   is  another exercise to try outside to show you  just  how
trust  worthy  a compass really is.  Get all your boys out to  do
this one. Place the end of a stick into  the ground  directly  at
your feet.    Set  your  COMPASS  ROSE,   or  Azimuth  Ring,   to
some arbitrary direction between 0  and  120 Degs.    (Let's  say
60  Degs.)  Now  turn your  body and Compass as a unit  till  the
Compass   Needle   points to the tape  (Declination).  Face  this
direction   and   walk  this bearing  for a nice  evenly   spaced
20 Paces...  (Double  steps, about 100 feet). Then stop.

OK.  Now  look at your Compass again.  Add 120 Degs to the  first
arbitrary  direction  you used,    (Like 60 Degs + 120 Degs = 180
Degs.) and set this  new  Bearing  on  your Compass Rose.  Again,
turn  your  body and Compass as a unit till  the  Compass  Needle
points to  the tape (Declination,  Not to North). Walk another 20
Paces... Stop.

Now  one last time.  Look at your Compass again.  Add yet another
120   Degs   to  your last setting  (180 Degs + 120  Degs  =  300
Degs), and reset your Compass  Rose. Turn  your body  and Compass
till  the  needle  points  to Declination  again,  then  walk  20
Paces again... Stop.

If  your  pace was smooth,  and evenly distanced,  at  your  feet
should be that stick...  This test is very good practice.  It can
instill a lot of faith in the compass...

Try 4 turns of 90 Degs each, or 5 turns of 72 degrees each.


BACK BEARING.
A  Back  Bearing,  means to reverse direction along the  way  you
just came,  or back tracking.  Simply add or subtract 180 degrees
from   your  present bearing,  and turn  the DIRECTION OF  TRAVEL
ARROW to this new heading, turn around and walk  back the way you
came.

Or another way with an Orienteering  Compass, you can simply hold
the whole compass  and Base Plate backward  in your hand, without
touching  the  Needle Housing,    and follow the Base Plate  back
the way you came.

HOW TO ORIENT A MAP
First  of all,  find True North with the Compass,  and align  the
Needle  to the tape (Declination,  Not North).  Open the Map  and
place it on a rock or the flat ground.  Turn the  Map so that the
Compass's  Meridian Orienting Lines and the Map's True North  are
aligned. Now the map matches the landscape exactly.

HOW TO GET A MAP BEARING, FROM THE MAP, TO THE LANDSCAPE.
Simply  place  the Compass on the open Map.  Put the  rear-corner
edge of the  Base Plate directly on your present  location.  Move
the straight edge of the Base Plate, into the direction you  wish
to  travel.  Now turn the Compass Rose till the  Needle  Housing,
Meridian    Orienting  Lines  match    the    Map's   North/South
lines.  That's all there is to it...

Now
pick up the Compass and hold it properly,   and turn it and  your
body  as  a unit,   till the  needle  points  to the  Declination
Tape   (Not   North).    The "Direction of Travel Arrow"  on  the
Base  Plate  now   points the  way to  go.    Sight on a  distant
object  beyond  your  target,   and fix it in your   mind.    Put
away  the Compass  and  walk towards your destination along  your
landmark bearing line.

As  you  walk you may find your self side stepping  obstacles  in
your  way.  Any time you step to the left or to the right of your
Bearing, say to travel  around boulders, or clumps of foliage, to
reach your destination landmark,  you practice  CIRCUMNAVIGATION.
Your  distant  visual  landmark brings you back to  your  correct
bearing. This is why "Steering Marks" are SO important.

Note, when using an Orienteering Compass, to get a MAP BEARING to
a  FIELD  BEARING,  the  -Map does not have to   be  oriented  to
North!

HOW TO PLOT A FIELD BEARING ONTO A MAP.
Hold  your Compass properly,  and turn your body and Compass   as
a  unit,   to  the direction you have visually decided to  travel
in.    Now,  turn  the Compass Rose till the Needle points to the
Declination  Tape   (Not  North).    This  is  called  "taking  a
bearing."  Then  place   the  Compass  on  an  oriented  (or  un-
oriented)  map.  Turn the whole device around until the  MERIDIAN
ORIENTING   LINES,    on  the Needle  Housing,    line   up  with
True   North  lines on the map   (North    to   North,    totally
ignore the magnetic needle at this point).  Align the rear-corner
of  the BASE PLATE to your present location,  and draw a line  in
the  direction  you just measured from the field.    This is  the
direction you are looking at to travel in. That's all there is to
it...

BIANGULATION TO GET A "FIX" ON YOUR PRESENT LOCATION.
Look  around outside and find a prominent point in the  landscape
that  can  be  identified  on  your Map.   It  can   be  a  lake,
mountain peak,   road intersection,   river fork,   water  falls,
railroad  track,    anything   that  can  be  seen  both  on  the
Map,   and  on  the landscape.  Then  hold your compass properly,
and  turn   your  body and the Compass,  till  the  DIRECTION  OF
TRAVEL  ARROW points to this  prominent  landmark  feature.   Now
turn  the  COMPASS  ROSE around until  the Needle points  to  the
Declination  Tape  (Not   North),  and  get  a reading or bearing
in  degrees.   Ok,  now  place  the compass  on your oriented (or
un-oriented)   Map,     and align the MERIDIAN  ORIENTING   LINES
with  the  Map's  True  North.    Draw   a light  line  from  the
landmark   back  towards your  position.    Now  take    a    2nd
reading from another prominent landmark  about  90 Degs away from
the  1st  bearing.  Again turn the COMPASS ROSE till  the  Needle
again points to the Declination Tape (Not North).   For a  second
time,   place  the compass on  your Map and  align  the  MERIDIAN
ORIENTING  LINES with the Map's True North,    and draw  a  light
line  from the  2nd landmark  back towards your  position.  Where
the lines cross,  is your  exact location.

TRIANGULATION.
This   is  the same as Biangulation,   only that you take  a  3rd
reading  from  the landscape,   and  mark  it  also  on your Map,
as  a form  of  checking   your location.  This works best if the
readings are about 60 Degs from each other,  and specifically not
close together.

PACE
Did  it  ever in your life,  make you curious as to how  come   a
statute mile is the uneven distance of 5,280 feet?  Well,  that's
the  distance that 1,000 paces would cover by a Roman foot solder
200  years B.C..   Our  modern  word "Mile" came from  the  Latin
phrase,  "Mille  Passus,"  meaning "1,000  Paces."   Today,  this
measurement is still very handy.

A  Pace is the double-step distance between  2 right,  or 2  left
foot steps.   It is about 5 feet in an  adult,    4-1/2  feet  in
older children,  and 2-1/2 feet  in  10  year old's.

There is roughly 250 Adult PACES in 1/4 mile,  and 500 PACES in a
1/2  mile.   It is amazingly accurate. Everybody  has  a slightly
different pace,  so measure your own by marking off 100 feet  and
see how many paces it takes  you to travel 100 feet. It should be
from 18 to 21 paces.

Time   and  distance are directly  related  to  each  other    in
navigation.

                    time  =  distance / speed



The work done  to  walk straight  up  a steep hill 100 feet,  can
be  greatly  reduced  by increasing  the distance over which  the
work is to be done,     as in switch-backing the hill.  That  way
the same amount of work is done over a longer time.

                    work = time * horse power

Distance judged by time alone in the wilderness is unreliable due
to the differing kinds if terrain.  It  takes about 20 minutes to
walk  a mile on open highway,  30  minutes  to walk through  open
woods,  30 minutes for thick woods or foothills.    So  your best
bet is to not use time,   but use your  PACE to measure  distance
in the wilderness instead.

During   the  planning stages of a trip,  it is wise to plan each
nights  stay at each camp site.  The time and distance can be  an
important  bit of information.   But they are tricky to figure if
you  don't have some idea of the time it takes to pace a mile.

The standard
times to calculate travel time with a 35 pound backpack on is...

Ascending   - 1  hour for every 2 horizontal miles,   plus 1 hour
for  every  400 vertical feet of elevation gain.

Descending   - 1   hour  for every 2 horizontal miles,   plus 1/2
hours for every 1,000 vertical feet of elevation lost.

This rate takes into account for a 10 minute break every hour.

The health  of your group,   the age of the individual,  the type
of  landscape  walking  through,    and  expected  weather,  will
all have an effect on  the amount of time its going  to take.  So
the above times  are only a rough  idea.

CIRCUMNAVIGATION
While    you   are  walking on a Bearing,    you may come  to  an
obstacle   of  some kind.  It may be a lake,  a clump of  cactus,
a  swamp,  a  canyon,   or  a steep hill.  Something you can't go
through.

One   method is turning 90 degs to the right  or  left  of   your
present  course,  and taking a new bearing.   Then while  walking
away,  count  every right foot step,  till you clear the edge  of
the obstacle. Then turn and take another bearing at  -90 degrees,
to parallel your original heading. You do not have to count again
yet. When you have gone far enough  to clear the obstacle on this
parallel  direction,  turn -90 degrees  and take a new  temporary
Bearing.  Walk,  again counting every right foot step,  until you
have made the same number of paces that you first  counted.  When
you have reached the pace count,  turn +90 degrees, and resume on
your original Bearing, to continue on your way.

Instead   of  taking  the chance of forgetting    your   original
bearing  after you move the setting,  another   way   of  finding
that   90  Degs to turn,  is to take advantage of your  Compass's
base  plate.

When you get to that obstacle,  hold the Compass level, and sight
along   the  back edge to a distant  object   (Steering Mark)  at
90 degrees from your course,   and count  your steps  toward  it.

Then   sight along the  right  edge  of  the  Compass  and   walk
for  enough distance   to  clear  the  object.Then   sight  along
the  bottom edge again  - recounting   your steps back - and  get
back on  your  original heading.

DOG LEG (Advanced)
Another  method involves taking only a +45 degree turn,  for some
number of paces. Then  when the obstacle is  cleared, turning -90
degrees,    counting   your   paces  again,  where you  turn  +45
degrees to resume your original Main Bearing heading.

When  you  become really good at circumnavigation,  you can set a
Bearing. Then circumnavigate at +45 degrees  in  one direction of
an obstacle for some number of paces.  Then  turn back  -45  Degs
to  parallel  your  original main bearing for a   while   without
counting.    Then  turn another -45 degrees,    and recount  your
paces  again,    back  towards   your main bearing.    Where  you
again   turn  +45 degrees to  resume  your original course.  Cake
Walk!

Actually,    hiking  can rarely ever be done in a straight  line,
Mankind  has  a tendency  to  walk in circles,   and the land has
so  many  irregularities.   You improve the odds of reaching your
destination if you...

1.  Make careful,  and accurate sightings on both the Destination
     Landmark,  and all Intermediate Landmarks.

2. Follow    the  DIRECTION OF TRAVEL ARROW and NOT the   Compass
     Needle  when walking.

3.  Recheck  your bearings carefully to avoid an accumulation  of
     small  errors.  If  possible have more than  1  person  take
     Bearings.

4. Use bearings only over short distances when possible.

5. Aim for a "line" on a Map rather than a "point" when possible.
     These are called "handrails." It is easier to hit a  stream,
     a road,  or a crest, than it is to hit a waterfall, or water
     tank.

6. Continuously plot your progress on a Map.

DEAD RECKONING, Aiming Off, or Offset Course. (Advanced)
This  is  a technique involving the  knowledge  of  distance,  in
Paces,  between   you   and  some destination on  a  Map.

By  calculating  the correct number of paces,  and  then  walking
deliberately  to miss the object on  one side, you keep  track of
exactly  where  that  destination  is.  It give you a  bit  of  a
"handrail."


For  instance,  if  you knew you were say 300 paces west, outside
of  camp,    and  you headed directly east,  into camp, in  thick
brush you may, or  may not, hit  the  camp directly head on.  You
most  likely  will end up a little North  or  South  of the  camp
site.   But  you   notice   that   after  arriving   in  the  new
location,   you still don't see the camp.  Now which direction do
you go from here?   Try all of them!!! You could very conceivably
spend  quite  a  bit of time  looking  around   without   finding
anything.

By  purposely  walking 10 degrees off to one side (south  of  the
camp), and walking east while counting the 300  paces. By turning
90  degrees north like clockwork,  you will measurably be in  the
vicinity  of the camp.  This greatly increases your  chances   of
hitting the camp.

CONTOURING  is  a  method of walking around an obstacle,  such as
a  hill,   by keeping at the same elevation,  and thus  following
the   contour.   This reduces the work expended by climbing   and
descending the hill,  keeping you from exhausting yourself.

FOG BANK READINGS.
The  #1 first  rule of backcountry hiking is -

              Never get lost in the first places.-

This may bring up the question of "how," but it is important that
everybody  needs to "know where they are on the map" before  they
first  hike out  that day.  And  every so often "along the trail"
they need to check exactly  where they are.

It   is  best to have the map & compass close at hand in a  shirt
pocket,   and  not stuck in a backpack pocket somewhere. You must
you  must  be able to get to your  Map in 5   seconds,  and  your
Compass in 10.

In fair weather,  you might not have any need of your compass  at
all.  You may be able to orient yourself with only with a Map and
landscape features.

But   if  the weather deteriorates while your on  the   mountain,
and  limits  your visibility,   you'll  need  to heavily rely  on
your compass by setting the bearings you want to  follow from the
map.

The  mountains   create  their  own weather  and  sudden   Indian
Summer   snowstorms  do  occur  regularly in the  Sierras  around
June   and August.  On a 2nd or 3rd day out,  it can take  only 3
seconds for a cloud  bank,  rising over a mountain spine,  to pop
up over the 10,000 foot,   marmont infested,  rock quarry  you're
on, and leave  you with a reduced visibility of 0 feet.

And do not  forget to look behind  you as you travel.  You should
be concentrating more,  on what you have passed,  than where  you
are  going.   The  landscape   looks   very    different  looking
back  the  other direction.    Turn around and look at once in  a
while.

It  is  unlikely that a Compass will become damaged,  but  it  is
always possible.  If  you  go  into the  wilderness, always carry
another  compass as back up, preferably carried by  someone else.
One  person may become incapacitated,  so there should  always be
another who  can also  navigate safely.

OTHER METHODS FOR FINDING NORTH.
A  stick,  driven   into  the ground,  so that the  stick  points
directly at the sun,  and has no shadow.  Within 20   minutes,  a
shadow  is forming,  and a line is drawn in the dirt to  continue
the shadow east and west. The stick then points away from North.


At    night,    the   big  dipper's 2 bowl  stars  point  to  the
fainter pole  star called  Polars.     What  ever latitude on the
globe you observe Polaris from,   is the   same number of degrees
above the Northern horizon that Polaris will be found.  (i.e.  at
34  Degs  N Lat...  Polaris will be seen at 34 degrees above  the
Northern horizon.)

The head of winter constellation Orion points to the North.

Tree  stump  annual   growth  rings are usually  thicker  on  the
Northeast side of the cut.

Away  from moist areas like stream beds,  moss has a tendency  to
grow on the shady North side of a tree.   In damp areas, however,
it grows all over the tree.

Lichens  and Algae on boulders,  grow more on the sunny  Southern
sides.

WEATHER FORECASTING USING A COMPASS
Weather  is a fairly complicated subject that could use an entire
training  session  of it's own.   However any good   Encyclopedia
can  help you better understand the fundamentals  of  Meteorology
and  Weather.   Whether  you  captain  a  yacht,    hike  in  the
wilderness,  or  just sit on your porch,  weather is one of those
unique  topics that can enrich the rest of your life.

Very briefly however,  the Sun is the energy source that heats up
the engine of our atmosphere.  As the tropical air at the equator
heats up,  it slowly rises up and over the heavier, colder, polar
air, that is sinking at the poles, slipping southward.

At  the  same  time  the  heavier cold  air  is  sinking  in  the
atmosphere,   the   Earth   is  spinning, dragging the atmosphere
along.  Due    to   centrifugal   forces,    and   the   Coriolis
(kor-e-O'lis)  Effect,   this slings a vortex of more dense polar
air  towards  the  equator in a 600 mph curved path  called   the
"Jet Stream."  This causes the Trade Winds that blow from West to
East along the latitudes of the western United States.






The  warm  and  cold  air masses do not mix   well  due   to  the
differences in temperature and moisture,  and pockets of Higher &

·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (15:54)             Number: 2506          Message    6 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)
Lower  air pressure develop.  A High is literally where air  just
piles   up  on top of itself as it spins off of the  Jet  Stream.
These Highs and Lows of atmospheric pressure,  in turn create the
weather  fronts  reported on by the News  and   Weather  Services
during the day.

As   these  atmospheric  Highs and Lows pass  through  an   area,
there  are  characteristic wind,   and cloud  patterns  that  are
observable, which can really aid you in forecasting the next  12,
24,  or 48 hours.

In areas of High air pressure,  the air circulates Clockwise (CW)
around the center, and out away from center.

In  areas  of Low air pressure,   the air   circulates   Counter-
clockwise (CCW) around the center, and into the center.

This  direction of -Low- air circulation is very  important.  One
way to  remember  this,   is when the clouds  are  forming,   and
the weather is getting worse (a Low), turn and face the wind head
on.  The central  area of Low Pressure will be on your right hand
side,  at 90 Degs  from you.

Basically  what this means is,  if the   winds hit you out of the
West,   then  the "Low Pressure system" will pass-by you  to  the
North.  It may give you a short  light rain,   or no rain at all.
However, if the wind has an element of South  in it, look out. It
may be coming directly your way.

Winds out of the  Southwest,  South,  or Southeast, mean that the
Low   is   directly  West  of  you.  The  Trade  Winds  will   be
carrying  it  over  your area in  just  a matter  of  hours.  You
should  be able to see signs  that  it  is either a  Warm,  or  a
Cold  Front,   and whether it will pass over you.  Depending   on
the   season,  this   may  be a direct warning to get your  group
down out of  the  mountains  as soon as possible,     and without
delay.  Your first sign  of trouble may be a cold afternoon wind,
blowing along the ground,  out of an unusual direction, watch and
feel for it.

















  Wind        Barometric      Weather
Direction      Pressure     Prediction
----------------------------------------------------------------
 N to E...... Rapid Fall.. Gale Due In Hours,  Snow or
                            Heavy Rain Continuing.
 NE to E..... Rapid Fall.. Rain Or Snow in 12 to 14 Hours.
 NE to E..... Slow Fall... Rain in 2 To 4 Days, Or Winter Snow
                            Within 24 Hours.
 NE to SE.... Rapid Fall.. Rain With High Winds, Then Clearing
                            Within 36 Hours.
 NE to SE.... Rapid Fall.. Rain In 12 Hours With Wind.
 NE to SE.... Slow Fall... Rain Continuing.
 NE to SE.... Slow Fall... Rain In More Than 12 Hours With Wind.
 E to S...... Rapid Fall.. Severe Storm Due In Hours, Then
                            Clearing.
 SE to S..... Rapid Fall.. Rain Within 12 Hours With Wind.
 SE to S..... Slow Fall... Rain Within 24 Hours.
 SW to S..... Slow Rise... Clearing Within Hours, Then Fair
                            Weather For Days.
 Moving to W. Rapid Rise.. Storm Ending, Clearing and colder.
 NW to SW.... Rapid Rise.. Fair With Rain In 48 Hours.
 NW to SW.... Steady...... Fair For 24 To 48 Hours.
 NW to SW.... Slow Fall... Fair And Warmer For 48 Hours.

Highs  are fair weather pockets of air,  after the front  passes,
and  not  usually a problem.   High Cirrus or "Mares Tails"  will
give about  48 hours warning before the passing of a Warm  Front.
It may sprinkle a little,   but will most likely  not be  severe.
Warm Fronts generally move more slowly, at about 8-10 mph.. Rain
will last for about 24 hours or so,  and in 48 hours temperatures
will warm up.

A  Cold Front moves much faster at about 15-40+ mph..  It  wedges
and  pushes   the  warmer pocket of air along in front  of    it,
and   can generate huge towering clouds,   with very severe rain,
hail, and  even  lightning.

A Cold Front does not have Mares  Tails.  Instead  takes  on  the
characteristic  form of a "line of  clouds"  that comes  in  from
the  coast,    or creeps up over a mountain range.  It   carries,
and  dumps  lots of  rain,    and  can  easily  form Cumulonimbus
Thunderheads. (To calculate the distance away from a storm having
the flash and sound of thunder,  count  the interval between  the
lightning  flash,  and the boom,  and allow 5  seconds  for  each
mile.) A Cold Front is exactly the kind of weather to avoid  from
November   15th  till March 31st at 6,000 feet.

As the Frontal Zone of a storm passes over head,   the  wind will
noticeably shift 90 Degs. A Cold Front type storm will be over. A
Warm Front storm however,  is only half over. This has to do with
the way clouds are made in the Frontal Zone itself.

In a Warm Front,   the warm air is riding up and over  the cooler
pocket of air on the ground, and is pushing it along more slowly.
The  clouds  of a Warm Front are almost horizontal at  200  miles
out,  as they gently slope  back  towards the  ground.  These are
Crrius  and Straitus Clouds  typical  of Warm Fronts.

As   the  Warm/moist   air  and the  Cold/dry  air  meet  in  the
"Frontal  Zone," condensation takes place forming fog,  and falls
to   earth  as   rain.  So when this long  sloping  Front  passes
overhead,   the wind will shift, but it will continue to rain for
a bit longer.

What makes it really interesting is that not all weather patterns
are predictable.  Even T.V. Weathermen are only correct 80 or 90%
of the time.  Besides that they can only see about 36 to 48 hours
a  head.  Always be prepared with rain gear!  Surprise storms  do
occur regularly,  but let me clue you, the surprise of weather is
wonderful.

It's going to be up to you. Learning the patterns of weather, and
trying to out  think it, is interesting. Predicting  weather is a
skill of the natural world, that can be as important as using any
map & compass.



"I  only  went out for a walk and finally concluded to  stay  out
till sundown,  for going out I found,  was really going in."
                                                      John Muir

                     **********************
                     * IF YOU BECOME LOST *
                     **********************


The   act   of   traveling to some  unknown   place,  from   some
unknown  place,  can  only be called one thing...  LOST!  If  you
should find yourself mixed-up, and in unfamiliar territory, don't
call   yourself   lost  right away.   You may  just  be  slightly
disoriented for  a  few minutes.   What ever else you do,   don't
panic.   Panic  can  cripple your  ability to  think  rationally,
and greatly reduce your  chances  of ever getting out safely.

You can take heart. Every  year, thousands of people become lost.
Luckily, most of them figure out where they are,  or are found by
Rescue  Teams  within a few hours or  days.

-Sit  down- and   relax.  Take your time.  Have a deep breath  or
two.  Eat a  candy bar,  chew  some gum,  drink some water. Think
things  over and stay quiet for a few minutes. Look  around,
and enjoy  your surroundings.

Try to remember how you got there.  You may  remember how strange
the trail looked when you accidentally took that wrong turn  onto
an animal trail,  or maybe you must have simply missed  the trail
sign.  Study  the  Map  and  landscape  for   clues,  shoot  some
bearings,  and  above all STAY  TOGETHER AS A  GROUP.  The  buddy
system is not only for swimming.   Never leave your gear anywhere
as you scout around the area. You may not be able to find it once
you leave it, and it is your life line. Climb a tree or   hill to
see  where  you are.   Get your mind  working  for    you,  think
positive. Speak up, and get everyone involved, someone might have
seen something you have missed.

When  someone  on foot first recognizes that  they may  be  lost,
they are usually not so far out that they can not be located,  or
even relocate themselves in a short time.

The major problems begin when a lost hiker,  who knows he's lost,
keeps right on walking along,  thinking he'll figure out where he
is.  At   the same time,  he's increases the confusion  for   the
Search & Rescue teams.  Sadly,  all too often,  the victim  walks
entirely  out of the search area.

Keep  a  cool head.  Having a good mental attitude can  mean  the
difference between a pleasant unscheduled camp out, or a life  or
death survival situation.  Things are usually not as bad as  they
first appear.

TEACHING SCOUTS HOW TO STAY FOUND.
[]  First,  concentrate  on teaching kids what to  do   if   they
     suddenly   feel  lost...  S T O P !  If  they  can't  figure
     out where they  are,   tell  them to make lots of noise.   3
     of   anything,  3  whistle  blasts, 3  rock   bangs,   means
     H E L P!  Do not move!  WAIT TO BE FOUND!  And keep  making
     noise.

[]  Always  have  them  tell somebody if they have to  leave  the
     trail for  any  reason. Even to stop and  rest.  Always  use
     the buddy system in the wilderness.

[]  Explore  only inside set camp boundaries,  and enforce  those
     boundaries.

[]  Show  them how to recognize trail signs along  the  way.  Use
     their un-quenchable  thirst for details.   Point to features
     along the way both large and small.

[]  At rest stops,  and in camp,  play games about things  around
     them.  Have them close their eyes and name things. Have them
     name landscape  features  on  the Map.   As you  hike   show
     them   your progress along the way on the Map to check their
     position.

[]  Have  them  look around and find a prominent feature  of  the
     landscape  that can help them stay found.

[]  Teach  them how to use a Map and Compass and  let  them  take
     turns leading the group.

PLANNING A TRIP.
You have placed a hike on the Troop calendar. There is this great
hike you have always heard about.  So it's time to make plans for
everybody to make that hike.  Your planning starts right   there,
and should not end till you are back safely from the trip.

There  are all kinds of books,   and trail guides,   that you can
purchase.  These  will tell  you about almost any hike.  They are
most often a great  place  to start.  You  will be able to get  a
good  idea of what others think about that dream hike  of  yours.
Many   times   they will give a little history  about  the  area,
and point out some interesting sights along the way. You can also
learn  about  some possible side trips to places  that  you  just
otherwise would have passed by. Many times these guide books will
tell you exactly where the hike starts,  how to drive there,  and
if  the   campgrounds  have water close by,  etc..  They  can  be
wonderful,   but   do remember that the older the book,  the more
likely that things have changed.




------------------------------------------------------------------------------
 Date: 01-01-94 (15:58)             Number: 2501          Message    1 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
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(3/4)
Often   these  books will come with a general Map  of  the  area.
They show all the hikes that are listed in the book. You can  get
a  better  feel about the hike you want to  go  on,    and  about
other   hikes  in  the  general area.  These are good to study in
case you have to alter your plans along the way.  There might  be
something else that you decide you want to do, like  go swimming.
It maybe only a short distance from  where you plan to be.  These
Maps  can give  a fair amount of  detail,  but they should not be
used instead of the Topo for the area.

Many   agencies will make Maps showing  all the  hikes  in  their
area  of  control.    The  Forestry  Service does  this  here  in
California.    The  cost is 2$.  These often have quite a bit  of
detail,    but   they  are not as informative as  a   Topo   Map.
Forest Service Maps come in all sizes,  and are often some of the
most  updated  facts on that area.  There are also,  many  times,
short  footnotes on each  hike,   and  about   water  conditions.
Many  times  they will  explain  the Wilderness   Permit  system,
or  show you which Fire Permit you'll need to  get,   and give  a
few  of the  regulations  for that area.    If trails are  closed
at certain times of the year they will often be noted.

The  people who have control over the area where your  hike,  are
often  the best source for current information about  that  area.
Things can really  change from year to year,   and Topo Maps just
can't keep up. Thru  talking  with people who know the area well,
you can find out information that no Map can  show.    There  may
be  a  short sheer cliff that the Map doesn't show.    The  water
routes  may  have changed over time.    Bears may be raiding only
certain camp sites and leaving  others alone.    Or there may now
be   a  shortage of water in  the  area.  These are things you'll
need to know before you leave, and not just find them out  on the
trail.

Use   and   study all the Maps you can get your hands on of   the
area.   Road Maps,   Forest Service Maps,  Trail Guide Maps,  and
even Complementary  Visitor Center  Maps.    Something may happen
on the trail that may cause you to  change your route,    or come
out  another way.   In an emergency you may be able to save  time
in   getting help by going cross country,  instead of the way you
came in.  You should know all roads around the area.

Make  a written plan of events with times and locations.   Add in
some time for the unexpected.

Let everyone see the  plan.  Leave it with someone back  at home,
with instructions of what to do, if they don't hear from you by a
set date and time.



Also let   all  parties  know who to contact in  case  there   is
an emergency  at home,  and they need to get word to your  group.
It is also good to leave a Map at home, highlighting your route.

Make   some plans for an alternate hike.  You may need to make  a
change   due    to events beyond your control.  Weather can  very
easily  make  it so you can't  hike in one  area.  Yet  maybe  by
moving  over to another trail,  just a few short miles away,  you
can still go on a safe outing.  Never feel that you have to  make
that one hike right this instant.

Is this hike of a nature that everyone in the group will be  able
to make it, or will  there be a need for some special training to
get everyone   ready? Don't let  someone  go, if there is a valid
reason  why  they "might" not be able to  make  the  hike.  Flu &
Colds  tend to get worse up on the mountain.   Know your  limits.
The  more you can learn about an area,   and your groups  limits,
the   safer  your hike will be.  Make everyone going,  study  the
maps,   and   put some input into the planning.    Find out  what
they  want  to see. Make  your  Scouts feel like  this  is  their
outing,    not  the leaders.  BSA requires 2 adult leaders,  1 of
which   has  to  be 21 years  of  age.   That  no  fewer  than  4
individuals go on any  back country hike or camp out,  and file a
Local Tour Permit with BSA.

Stop   by the Ranger's Station on the way in,  let them know your
group is on the mountain.  Collect all the  information  you can.
Then  go out there and enjoy the back country with all it has  to
offer,   and   wisely   plan ahead so you can enjoy  the   beauty
around you...

ORIENTEERING  was developed in Sweden as a sport.  It is  a  game
that   improves  map  reading  skills.   and  is  a   competitive
navigational "run for your money."  Each player,   outfitted with
a  map,   a  compass,   and  a set of clues,   takes    off    at
spaced intervals,    to locate a series  of  control points,   in
a  timed race.    Mental and physical skills are needed for  this
type  of game.   Someone skilled in the use  of  map  &  compass,
with  care and quick thinking,    can off set their own  weakness
in strength  or endurance.

Players need to understand all about map reading,  bearings,  map
     scale,  map orienting, direction, symbols, and contours.

In  "Point To Point Orienteering," all of the control points  are
     visited in the same sequence by players.

In  "Score Orienteering," none of the control points need  to  be
     gone  to  in any certain sequence.   A different  number  of
     points are given  to each control,   depending on the amount
     of difficulty  in reaching them.  Some controls are   placed
     far   away from the start.   Maybe on  the  other side of  a
     stream,   or   the other side of hills.  There  is   usually
     more control points than time  in  the event, so that no one
     can reach all of them.

In "Line Orienteering," the whole course is marked only by a line
     on the Map.

In  "Route  Orienteering," the landscape is marked off with tape,
     and each player marks every control point on their map.

Arrowhead Sheriff's Department Phone # [phone]
Search & Rescue Phone # [phone]
San Bernardino Forest Service Dispatch Phone # [phone]

Where to purchase Maps.
Map Distribution,   Geological Survey,   Box 25286, Federal
   Center, Denver, Co. 80225
Allied Services, 966 N.Main St. Orange Ca 92667 [phone]
Redlands Blueprint Company, 1075 W.Redlands Blvd. [phone]
Di Line Corp., 197 S."D" St. San Bernardino, [phone]
Sports  Country  Limited,  222 N. "G" St. San Bernardino, (909)
   825-2976 Riverside Ski Sport, 6744 Brockton Ave., (909)
   784-0205






-----------------------------------------------------------------
A 6% grade is a 6 foot rise in elevation every 100 feet.

6ft / 100ft = .06 = 6% grade (normal)

An angle of 12 degrees as measured from an Inclinometer is a  13%
grade.

 90 degrees    100% grade
------------  x  ------  =  (12 x 100 = 1200)/ 90 = 13.33% grade
 12 degrees     ? % grade
                                         Huffin' & Puffin Steep!


An    elevation   change   of   1,000   feet   in   a   mile   is
considered  respectably steep (19% grade).

1,000 ft. / 5,280 feet = .189 = 18.9% grade

-----------------------------------------------------------------















INCLINOMETER measurements, part A. (Advanced)

Anybody   can   easily  learn  how to  use  the  Inclinometer  to
determine the  height  of an object,  like trees, water falls, or
mountain peaks, by using very simple trigonomic mathematics.

       (B)
          *
          *   *     Hypotenuse
Opposite  *       *
Side      *           *      Tangent
          *            /  *    Angle
          *           /      *
          * * * * * * * * * * * *  (A)
                Adjacent Side


The    Distance-of-the-Opposite-Side   is   determined   by   the
Distance-of-Adjacent-Side  multiplied by the  Tangent-of-`degree-
of-Incline', found on the compass.

or...

Opposite = Adjacent * Tangent ( of Degree of Incline )


TANGENT LOOK UP TABLE
Degrees = Tangent
1  .0174       24 .4245       47 1.072       70 2.747
2  .0349       25 .4663       48 1.111       71 2.904
3  .0524       26 .4877       49 1.150       72 3.078
4  .0699       27 .5095       50 1.191       73 3.271

5  .0875       28 .5317       51 1.235       74 3.487
6  .1051       29 .5543       52 1.280       75 3.732
7  .1228       30 .5774       53 1.327       76 4.011
8  .1405       31 .6009       54 1.376       77 4.331

9  .1584       32 .6249       55 1.428       78 4.705
10 .1763       33 .6494       56 1.482       79 5.145
11 .1944       34 .6745       57 1.540       80 5.671
12 .2126       35 .7002       58 1.600       81 6.314

13 .2309       36 .7265       59 1.664       82 7.115
14 .2493       37 .7536       60 1.732       83 8.144
15 .2679       38 .7812       61 1.804       84 9.514
16 .2867       39 .8098       62 1.881       85 11.43

17 .3057       40 .8391       63 1.963       86 14.30
18 .3249       41 .8693       64 2.050       87 19.08
19 .3443       42 .9004       65 2.145       88 28.64
20 .3640       43 .9325       66 2.260       89 57.29

21 .3839       44 .9657       67 2.356       90 infinity
22 .4040       45 1.000       68 2.475
23 .4245       46 1.036       69 2.605


HOW TO FIND THE HEIGHT OF A TREE.
First, stand next to the tree, and count out some number of paces
away from it. (5, 10, 50 etc.) Say 10 paces this time.

Stop,  turn, and take an Inclination reading on the tree from eye
level. Say the reading is 28 Degs.

(Knowing that my pace is, 100 feet equals 18 paces.)
The distance to the tree is...

                                 18 paces      100 feet
                       Ratio :  ---------- =  ----------
                                 10 paces       ? feet

   Show Work...
    (10 paces * 100 ft = 1,000 ) / 18 paces = 55.5 feet from base
          of tree.


The  Tangent  of 28 degrees is .5317
     (as determined from the Tangent look up table.)

The tree height from your eye level is...

                           55.5 ft * .5317 = 29.5 ft



Now add your height from the ground to your eye level (5 feet)...

                                29.5 ft
                               + 5.0 ft
                             --------------------
                    The tree is 34.5 feet tall.


INCLINOMETER measurements, part B. (Advanced)

As  another  example on how to use this feature,   lets say  that
your  group is up on a 8,540  foot  Peak (A).  You can  look down
into  a river gorge (B), that  just doesn't  look  all  that very
far  away.  You  would like to send people for  water,  but   you
first   need  to determine how far away the river  is.  How  long
it will  take your people to reach it, and then get back.

    *A
   /. \._      _
  / .    \._  / \_
 /  .       \/    \_
/   . . . . .*B     \
----------------------
    [--------]
     1,800 ft





Step 1...
  Determine by Triangulation your exact position on the map.

  You   find while checking the map,   that you are 1,800 feet
      (1/3 mile)  from the water.


Step 2...
  Take an Inclinometer reading in Degrees down to the river.

  You find the inclination is 13 Degs.

Step 3...
  Convert "Degrees" into "Tangent."

                    13 Degs = .2308 (tangent look up table)

Step 4...
  Determine the difference in altitude.

                       1,800 feet * .2308 = 415.44 feet.


So the river is 416 feet down, at 1/3 of a mile out.


Step 5...
  Determine the time it will take to get there and back.

5a) Calculate for Horizontal element of hike.

     Down Hill Rules =
     1 hour for every 2 miles (10,560 feet),  plus (+),
     1 hour for every  1,000  feet lost in elevation.

     ( There are 5,280 feet in a mile.)



                        10,560 feet     60 minutes ( 1 hour )
                Ratio: ------------- : -----------------------
                        1,800 feet          ? minutes

     Show Work...
     ( 1,800 feet X 60 = 108,000 ) / 10,560 feet = 10.23 minutes
                                                    Horizontal


5b) Calculate for Vertical down hill element of hike.

                                 1,000 ft     60 min
                         Ratio: ---------- : --------
                                  416 ft      ? min

     Show Work...
     ( 416 ft X 60 min = 24,960 ) / 1,000 = 24.96 minutes
                                           Vertically (Down)

So it will take...

                    10.23 minutes horizontally
                   +24.96 minutes vertically down
                  --------
                    35.19 minutes to get down to the water.



5c) Calculate for the Vertical up hill element of hike.

     Up Hill Rules =
     1 Hour for every 2 miles, plus (+),
     1 Hour for every 400 ft gained in elevation.

                                  400 ft     60 min
                          Ratio: -------- : --------
                                  416 ft      ? min

     Show Work
( 415 ft X 60 min = 24,960 ) / 400 ft = 62.4 minutes (up)



So we have...
                    10.23 min horizontally
                   +62.4  min vertically (up)
                  -------
                    72.63 minutes to get back up from the water.



The Round Trip will be about...

                 35.19 minutes down
                +72.63 minutes up
                --------
                107.82 minutes = 1 hour, and 49 minutes (or about
                                                        2 hours)

Maybe  you  should  wait till the morning  to  fetch  that  water
instead.

INCLINOMETER measurements part C. (Advanced)

Let's   say that 2 hours before sunset,   your group can't decide
whether to make camp  at their present location (A),   or push-on
to   the  camp at the top of  the switch-backs.  You  as  Leader,
must decide how long it will take  the  weakest member,  to reach
the top, set up camp, and eat.

                  __
     /\          /  \
    /  \__/\ B  /    \
   /     /  \*_/      \_
  /    _/    (__       /\
 /  __/    _____)     /  \
/  /      (_________________* A


·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (15:58)             Number: 2502          Message    2 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)
Step 1...
  Determine by Triangulation your exact position on the map.

  You   find while checking the map,   that you are 3,600 feet
   (2/3 mile)  from   Site B.

Step 2...
  Take an Inclinometer reading in Degrees up to the Saddle.

  You find the inclination is 15 Degs.

Step 3...
  Convert "Degrees" into "Tangent."

                    15 Degs = .2679 (tangent look up table)


Step 4...
  Determine the difference in altitude.

                       3,600 feet * .2679 = 964.44 feet


So the Saddle is 965 feet up, at 2/3rds of a mile out.


Step 5...
  Determine the time it will take to get there.

5a) Calculate for the Horizontal element of hike.

     Up Hill Rules =
     1 Hour for every 2 miles (10,560 feet), plus (+),
     1 Hour for every 400 ft gained in elevation.

     (There are 5,280 feet in a mile.)


                        10,560 feet     60 minutes ( 1 hour )
                Ratio: ------------- : -----------------------
                        3,600 feet          ? minutes

     Show Work...
     ( 3,600 feet * 60 = 216,000 ) / 10,560 feet = 20.45 Minutes
                                                     Horizontal


5b) Calculate for the Vertical up hill element of hike.

                                   400 ft      60 min
                          Ratio: ---------- : --------
                                   965 ft       ? min

     Show Work
            ( 965 ft X 60 min = 57,900 ) / 400 ft = 144.75
                                                    minutes.


So we have...
                   20.45 Minutes Horizontally
                 +144.75 Minutes Vertically
                 -------
                  165.2  Minutes to get up the Switch-backs.


That's   2  hours and 45 minutes...    Maybe you should wait till
the   morning  to assault the Switch-backs.

-----------------------------------------------------------------

HOW TO FIND THE WIDTH OF AN OBJECT.
An   Object  that can not be directly measured like   a   stream,
lake,    river,  canyon  or crevasse,  can be measured indirectly
using the compass.

                         ()) ){)
                        (\(())}/)
                        ({}|))/)}
                  ___ ___ \[]_/  __
                 // // //\ []   /_/\
             _  //\//\///\ []  // |\\
             --------------|-\--------------------
               -=- - -=- - | -\  = -=- -=- -=- =_=
                 -=-   _-= |   \  -_-=-= -=- -=-
              _ -=-= - - _-| _= \  -=_  -=-  -=-=
             --------------|//---\--//--------\
                           //------//-----  *  \--
                           A      B \    | /|\
                                     \   |  |
                                      \  |  |   ?
                                       \ | \|/
                                      C \|  *


Step 1...
     Locate   an  object  directly  across  from you on the other
     side  to  use  as  a  reference.   a tree,   a rock,   or an
     outcropping.    Place  a stick in the  ground at your  feet.
     (A)

Step 2...
  Using   the  square  Base Plate of the compass,   turn 90 Degs
  away from  the  object.  Walk a determined distance counted in
  paces, (5, 10, or 50) and then  stop. Place another Stick in
  the ground. (B)

Step 3...
  Continue walking in the same direction,  the same number of
  paces again,  and then stop.

Step 4...
  Now  turn  90 Degs (away  from object),   and walk counting an
  unknown  number of  paces   looking  over your shoulder at the
  Second Stick  (B).   When  the Object  and the Stick line up,
  the distance to the object is known.
----------------------------------------------------------------
Very Advanced:

Believe it or not, there IS a way to stay oriented without a map.
It  isn't  going to show us where we might find water,  decide  a
suitable  route  through the woods,  or where to find  a  road...
quite like a  map  can.  However what it Can do is  amazing!   It
works  in the form of allowing you to tromp around the woods all-
day,  and then head  straight back to camp,  without needing   to
backtrack, or even  a map.

It  doesn't   even  require  that the compass be  True  North  or
Magnetic   North.  All  that  it  requires  is  the  Vectors  (in
degrees,)  from  our Azimuth Ring.   This advanced technique  can
save  your  "resources."  It does  however,   require  a  pencil,
paper, and a calculator that can do sin, cos, and arc-tangent.

In this part of trigonometry,  distance  (r),  has a relationship
to  degrees  (Q).  Using this relationship, we can  make  our way
directly straight back to camp,  no matter where we roam, or even
if  it's night or day.  The secret is,   that  we  need  to  keep
an   accurate   written   record   of   our   (1.Distance     and
(2.Direction.    Then,    to  find our way   home,  the last  and
final leg of the trip can be figured from  anywhere! Even without
a map!



-----------------------------------------------------------------
=================================================================

  Our 4 Math-"magic" Rules For Polar Rectangular Coordinates:

     x =r*(cos*Q)                        North
                                          |
     y =r*(sin*Q)                  x- y+  |  x- y-
                                          |
     Q =Arctan(y/x)           West -------*------- East
            ________                      |
        _  / 2    2                x+ y+  |  x+ y-
     r = \/ x  + y                        |
                                        South


  Q = Angle in Degrees     r = distance from center of circle

=================================================================
-----------------------------------------------------------------











Example 1:

Let's   say  we  we're in our 4x4's,   out in the middle  of  the
desert.   We could trek around all day with this method, and have
a  bearing  for home when we decide to head  back to  camp,  from
any location on the map, or off.

                                G         H
                                * ------- *
            LAKE               /           \
                              /             \    MOUNTAIN
                             /               \
           D        C       /   MOUNTAIN      \
           * ------- *     /                 I *
          /           \   /
         /             \ /
        /   LAKE        \
       /               / \
    E /             F /   \
     * ------------- *     \ B     A
                            * ---- *

As  an example,  let's say (A) is our Home Base,  and we know  of
this great  little dry lake bed 4 or 5 miles away, where our tire
tracks  wouldn't do the environment too much damage.   So we  get
out  the map,  and sight along bearing 2-7-0 degrees,  and  write
this down, along with our "start" odometer reading, and go. As we
move  around  the  desert,  we intend to keep a log  of  all  our
milage/distances,  and bearing directions,  on this little paper.
The chart's first entry would like this...

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles   Q Degrees      x      y
A-B   <10,342.7>     ?          ?        <270>        ?      ?
B-C...
|                                                               |
 ---------------------------------------------------------------

When  we arrive at the Dry Lake Bed,  we enter our "end" odometer
reading in the log:

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles   Q Degrees      x      y
A-B    10,342.7  <10,344.45> <1.75>       270         ?      ?
B-C...
|                                                               |
 ---------------------------------------------------------------







Then  we take a bearing to our next location,  and jot this  down
also...

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles   Q Degrees      x      y
A-B    10,342.7   10,344.45   1.75        270         ?      ?
B-C   <10,346.0>     ?         ?         <328>        ?      ?
C-D...
|                                                               |
 ---------------------------------------------------------------

Each  time  we change bearings,  we write  down  accurately,  the
distance covered,  and new bearing. By the end of the day our log
may look like this:

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles   Q Degrees      x      y
A-B    10,342.7   10,344.45   1.75        270         ?      ?
B-C    10,346.0   10,349.5    3.5         328         ?      ?
C-D    10,346.5    10,352     2.5         270         ?      ?
D-E     10,352     10,355      3          212         ?      ?
E-F     10,355     10,359      4           90         ?      ?
F-G     10,359    10,364.5    5.5          33         ?      ?
G-H    10,364.5    10,367     2.5          90         ?      ?
H-I     10,367    10,369.5    2.5         152         ?      ?
-----------------------------------------------------------------
I-A      ?           ?         ?           ?        ?         ?
|                                                               |
 ---------------------------------------------------------------

Well,  the gas tank is getting a bit low now, and we need to plot
our way back to site (A)...


All we do is calculate for x and y:

When:       x =r*(cos*Q)      y =r*(sin*Q)

Then: Trail A-B..  x =1.75*(cos*270)= 0

                   y =1.75*(sin*270)= -1.75













And so forth, on down the list...

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles  Q Degrees      x      y
A-B    10,342.7   10,344.45   1.75       270     <   0  ><-1.75 >
B-C    10,346.0   10,349.5    3.5        328     < 2.968><-1.854>
C-D    10,346.5    10,352     2.5        270     <   0  >< -2.5 >
D-E     10,352     10,355      3         212     <-2.544><-1.589>
E-F     10,355     10,359      4          90     <   0  ><   4  >
F-G     10,359    10,364.5    5.5         33     < 4.612>< 2.995>
G-H    10,364.5    10,367     2.5         90     <   0  ><  2.5 >
H-I     10,367    10,369.5    2.5        152     <-2.207>< 1.173>
-----------------------------------------------------------------
I-A      ?           ?         ?          ?        ?         ?
|                                                               |
 ---------------------------------------------------------------

To find  the  distance (r), and  direction (Q), back to (A), from
wherever  we decide  to stop (I),  we simply add each column of x
and  y,   and calculate our homeward bearing of (Q)  degrees,  at
(r) distance.

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles   Q Degrees     x      y
A-B    10,342.7   10,344.45   1.75        270        0    -1.75
B-C    10,346.0   10,349.5    3.5         328      2.968  -1.854
C-D    10,346.5    10,352     2.5         270        0     -2.5
D-E     10,352     10,355      3          212     -2.544  -1.589
E-F     10,355     10,359      4           90        0       4
F-G     10,359    10,364.5    5.5          33      4.612   2.995
G-H    10,364.5    10,367     2.5          90        0      2.5
H-I     10,367    10,369.5    2.5         152     -2.207   1.173
----------------------------------------------------------------
I-A      ?           ?         ?           ?      <2.829> <4.725>
|                                                               |
 ---------------------------------------------------------------

We  can  tell already by the positive polarity of x and  y,  that
the general direction home is South West of us.

                              North
                                |
                         x- y+  |  x- y-
                                |
                    West -------*------- East
                                |
                         X+ Y+  |  x+ y-
                        *       |
                              South





The next step is to figure for r and Q.

Where:   Q =Arctan(y/x)

Then:
              Step 1             Step 2          Step 3
     Q =Arctan(4.725/2.829) = Arctan(.598) = 59.089 degrees


And  again because x and y are positive,  we already know home is
South West of us.  So we need to either add,  or subtract, 180 or
360,  to  make the answer come out in the correct corner  of  the
compass. In this case I'll add 180 degrees to the answer:

                             Step 4
                             59.089
                           +189.
                          ----------
                   Answer = 239.089 degrees


And Where:     ________
           _  / 2    2
       r =  \/ x  + y


Then:               Step 1                  Step 2
                 _______________         ______________
         r = _  /     2       2   =  _  /                =
              \/ 2.829 + 4.725        \/ 8.003 + 22.325


                           Step 3
                           _____
                       _  /        =  5.507 Miles
                        \/ 30.328



Now we fill in the blanks on our chart:

 ---------------------------------------------------------------
|                                                               |
        Odometer  Odometer   Elapsed
         Start      End      r Miles   Q Degrees      x      y
A-B    10,342.7   10,344.45   1.75        270         0    -1.75
B-C    10,346.0   10,349.5    3.5         328       2.968  -1.854
C-D    10,346.5    10,352     2.5         270         0     -2.5
D-E     10,352     10,355      3          212      -2.544  -1.589
E-F     10,355     10,359      4           90         0       4
F-G     10,359    10,364.5    5.5          33       4.612   2.995
G-H    10,364.5    10,367     2.5          90         0      2.5
H-I     10,367    10,369.5    2.5         152      -2.207   1.173

·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (15:58)             Number: 2503          Message    3 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)
-----------------------------------------------------------------
I-A    10,369.5    10,375    <5.5>     <239.08>     2.829   4.725
|                                                               |
 ---------------------------------------------------------------

So  the  direction  for  home (I-A),  could be  calculated  in  5
minutes, and home is just 5.5 miles away, instead of backtracking
23.

From  this chart we can figure that we will travel 5.5 miles,  at
bearing 239,  and, when our odometer clicks over to  10,369.5, we
should be back at base camp, refueling.

The  5 or 7 minutes of calculation,  has saved us about 1 hour of
backtracking (at 20 mph).



Example 2:
                        C
                         *  Hills  * A
                        / \       /
               Mountain/   \     /   \
                      /     \   /
                     /  Bad  \ /       \
                  D *  Lands  *   Rock
                    |          B  Cliff  * G
                    |  * F
                    | /
                    |/   Water
                  E *

Here  we are at Home Base (A),   and our eventual destination  is
going to be downhill at site (G).  However,  we  have  to pick up
some water about 2/3rds of a  mile away  first,  and backtracking
uphill will be inconvenient.   In  the process  of getting water,
we have to circumnavigate several other natural barriers too.

Our first step will be to shoot a bearing over to (G),  and  then
find (G) on the map.   Let's say the bearing is 1-4-8  degs.  The
map  says its about 1500 feet away,  1/4 of a mile,  or about 300
paces.

         100 feet      1500 feet
Ratio : ----------- : ----------- = (20 * 1500)/100 = 300 Paces
         20 Paces         ?

We write this information down on our paper. r = 300 Paces (G-A).

We also write down the bearing from (A-G) as a "Back Bearing"
(G-A), on  our paper.

            148 degs forward = 148+180 = 328 degs back

 ---------------------------------------------------------------
|                                                               |
               r Paces    Q degrees        x           y
         G-A    <300>       <328>          ?           ?
         A-B.....
|                                                               |
 ---------------------------------------------------------------

Next,   we  shoot  a  bearing  to  (B),  our  first  intermediary
destination.  We read on the compass,  212 degrees,  and we write
this down.

 ---------------------------------------------------------------
|                                                               |
               r Paces    Q degrees        x           y
         G-A     300         328           ?           ?
         A-B      ?         <212>          ?           ?
         B-C....
|                                                               |
 ---------------------------------------------------------------

As  we walk to (B),   we count every right footstep  (Pace). When
we get to (B),  we find that we have covered about 250 paces.  So
we write this down also.

 ---------------------------------------------------------------
|                                                               |
               r Paces    Q degrees           x           y
         G-A     300         328              ?           ?
         A-B    <250>        212              ?           ?
         B-C...
|                                                               |
 ---------------------------------------------------------------

Then we shoot-and-write our next bearing to (C).

On  every  leg  of  the journey,  we  jot  down  each  change  in
direction,  and  each  distance covered.  When we finally, get to
the water,  and  fill  our canteens at (F),  our paper looks like
this:

 ---------------------------------------------------------------
|                                                               |
               r Paces    Q degrees        x           y
         G-A     300         328           ?           ?
         A-B     250         212           ?           ?
         B-C     250         328           ?           ?
         C-D     250         212           ?           ?
         D-E     200         180           ?           ?
         E-F     150          32           ?           ?
       ---------------------------------------------------
         F-G      ?           ?            ?           ?
|                                                               |
 ---------------------------------------------------------------

Now   we  can  calculate a straight line route to site (G)   from
our  present location.  (We may or may not need to circumnavigate
around  to  site (G),  but we already learned how to  do  this...
Right?)

First we figure for x and y.

Where:      x =r*(cos*Q)     y =r*(sin*Q)



 ---------------------------------------------------------------
|                                                               |
               r Paces    Q degrees        x           y
         G-A     300         328       < 254.41 >  <-158.975>
         A-B     250         212       <-212.012>  <-132.479>
         B-C     250         328       < 212.012>  <-132.479>
         C-D     250         212       <-212.012>  <-132.479>
         D-E     200         180       <-200    >  <   0    >
         E-F     150          32       < 127.207>  <  79.487>
         -----------------------------------------------------
         F-G      ?           ?            ?           ?
|                                                               |
 ---------------------------------------------------------------

Then we add the columns of x and y...

 ---------------------------------------------------------------
|                                                               |
             r Paces    Q degrees         x           y
        G-A     300         328         254.41     -158.975
        A-B     250         212        -212.012    -132.479
        B-C     250         328         212.012    -132.479
        C-D     250         212        -212.012    -132.479
        D-E     200         180        -200           0
        E-F     150          32         127.207      79.487
        -----------------------------------------------------
        F-G      ?           ?         <-30.395>  <-476.925>
|                                                               |
 ---------------------------------------------------------------

From  the polarity of x and y we can tell that our new  direction
to (G) is going to be in a North Easterly direction.

                             North
                               |      *
                        x- y+  |  X- Y-
                               |
                   West -------*------- East
                               |
                        x+ y+  |  x+ y-
                               |
                             South

 Now we can calculate for Q degrees, and r distance:

When:    Q =Arctan(y/x)

Then:

  Q =Arctan(-476.925/-30.395) = Arctan(15.69) = 86.353 degrees








Now,  because both x and y are negative,  and falls between 0 and
90 degrees, the number is correct as is.



And Where:       _______
             _  / 2    2
         r =  \/ x  + y


Then:        __________________         ___________________
         _  /      2          2     _  /
      r = \/-30.395 + -476.925   =   \/923.856 + 227457.46 =


                      ________
                  _  /
                   \/228381.31 = 477.89 Paces



So the completed chart looks like:

 ---------------------------------------------------------------
|                                                               |
              r Paces    Q degrees        x           y
        G-A     300         328         254.41     -158.975
        A-B     250         212        -212.012    -132.479
        B-C     250         328         212.012    -132.479
        C-D     250         212        -212.012    -132.479
        D-E     200         180        -200           0
        E-F     150          32         127.207      79.487
        -----------------------------------------------------
        F-G  <477.89>    <86.3>         -30.395    -476.925
|                                                               |
 ---------------------------------------------------------------

In  this way we find out that by  heading bearing mark 86 degrees
for 478 Paces,  we should  be standing on site (G).






















------------------------------------------------------------------------------
 Date: 01-01-94 (16:00)             Number: 2507          Message    7 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
Message-ID: <[e-mail]>
(4/4)
Example 3:
                 * A  Heliport
                /
               /
              /       Traffic
             /    D *   Accident    Polluted Lake
      City  * B    / \                Footage
      Hall   \    /   \                 * -------- * G
              \  /     \               / F        / Small Brush
               * C      \             /          /    Fire
            Gas Station  \           /          /
              Robbery     \         /          /
                           \       /        H *  Search &
                            \     /            Rescue Recovery
                             \   /
                              \ /
                             E *  Store
                                 Opening

Let's use an example of a News Helicopter,   flying  around  your
home  town.  Let's  say  he can cover  the  ground  at  a  fairly
constant rate of about 70 mph on a  good day.  As he travels from
scene to scene,   he'll buzz around in the target area for awhile
till he decides to leave for another News breaking  story. He may
spend 10,  20,  or 30 minutes at each location before  moving on.
Now pilots log everything anyway, so keeping a Distance/Direction
chart  is just a part of being a  pilot.   Truck drivers too  for
that  matter.  By writing down the times he arrives and  departs,
along  with the  direction he heads off in,   he'll be  able   to
plot  a straight line course back to the heliport at  the end  of
his long day.

Let's  say at 8am he leaves the heliport on bearing 212  degrees,
and  heads  Downtown  to cover a speech by the mayor.   He writes
this down.

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B  <8am>   ?      ?        ?          <212>       ?        ?
B-C....
|                                                               |
 ---------------------------------------------------------------

When he arrives, he jots down the time of arrival.

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B   8am   <9am>    ?        ?           212       ?        ?
B-C....
|                                                               |
 ---------------------------------------------------------------

This  is an elapsed time of 1 hour,  or 60 minutes which is  also
plotted.

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B   8am    9am   <1h>     <60>          ?         ?        ?
B-C....
|                                                               |
 ---------------------------------------------------------------

15  minutes later,  he hears on his police scanner,  that  a  Gas
Station   he  knows of,  has a "robbery in progress." So he  gets
out his map,  and takes a bearing of 148 degrees.  Plots it,  and
his time, and heads straight for the scene of the crime.

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B   8am    9am    1h       60          212        ?        ?
B-C <9:15>    ?      ?        ?         <148>       ?        ?
C-D...
|                                                               |
 ---------------------------------------------------------------

When  he arrives,   he then plots his arrival time,  and  elapsed
time.

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B   8am    9am    1h       60          212        ?        ?
B-C  9:15   <9:45> <34m>    <34>         148        ?        ?
C-D...
|                                                               |
 ---------------------------------------------------------------
















And  so on all through the day...  At the end of the day his  log
would look like this:

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B   8am    9am    1h       60          212        ?        ?
B-C  9:15    9:45   34m      34          148        ?        ?
C-D  10:02  10:58   56m      56           32        ?        ?
D-E  11:10  13:18  2h15m    135          148        ?        ?
E-F  13:25  15:00  1h45m    105           32        ?        ?
F-G  15:15  16:19  1h4m      64           90        ?        ?
G-H  16:35  17:35   1h       60          212        ?        ?
----------  -----  -----   ------     ------    --------  -------
H-A    ?      ?      ?        ?           ?         ?        ?
|                                                               |
 ---------------------------------------------------------------

When  the News pilot reaches the end of his day,  and he wants to
head straight home, he'll figure his chart for x and y:

Where:     x =r*(cos*Q)     y =r*(sin*Q)

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes  Q degrees     x        y
A-B   8am    9am    1h       60         212   < -50.882><-31.795>
B-C  9:15    9:45   34m      34         148   < -28.833>< 18.017>
C-D  10:02  10:58   56m      56          32   <  47.49 >< 29.675>
D-E  11:10  13:18  2h15m    135         148   <-114.486>< 71.539>
E-F  13:25  15:00  1h45m    105          32   <  89.045>< 55.641>
F-G  15:15  16:19  1h4m      64          90   <    0   ><   64  >
G-H  16:35  17:35   1h       60         212   < -50.882><-31.795>
----------  -----  -----   ------    ------    --------  -------
H-A    ?      ?      ?       ?           ?         ?        ?
|                                                               |
 ---------------------------------------------------------------

















Then the x and y columns are totaled.

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes  Q degrees     x        y
A-B   8am    9am    1h       60         212     -50.882  -31.795
B-C  9:15    9:45   34m      34         148     -28.833   18.017
C-D  10:02  10:58   56m      56          32      47.49    29.675
D-E  11:10  13:18  2h15m    135         148    -114.486   71.539
E-F  13:25  15:00  1h45m    105          32      89.045   55.641
F-G  15:15  16:19  1h4m      64          90        0        64
G-H  16:35  17:35   1h       60         212     -50.882  -31.795
----------  -----  -----   ------    ------    --------  -------
H-A    ?      ?      ?       ?           ?    <-108.548><175.282>
|                                                               |
 ---------------------------------------------------------------

He can tell from the polarity of x and y that home is North West.

                             North
                       *       |
                        X- Y+  |  x- y-
                               |
                   West -------*------- East
                               |
                        x+ y+  |  x+ y-
                               |
                             South

Then he will calculate for Q degrees, and r time:

When:     Q =Arctan(y/x)

Then...

     Q= Arctan(175.282/-108.548) = Arctan(-1.614) = -58.231


Now because x is negative, and y is positive, he will need to add
or  subtract 180 or 360 to get the correct answer for that corner
of the compass.

                            -58.231
                           +360.
                           --------
                     Answer 301.76 Q degrees










And When:            _______
                 _  / 2    2
             r =  \/ x  + y


Then....   ___________________        ___________________
       _  /       2         2     _  /
    r = \/-108.548 + 175.282   =   \/11782.668 + 30723.78  =

                    ________
                _  /
                 \/42506.448  =  206.17 Minutes



So his completed chart would look like:

 ---------------------------------------------------------------
|                                                               |
                           Elapsed
     Start  Stop  Elapsed  Time In
     Time   Time   Time   r Minutes   Q degrees     x        y
A-B   8am    9am    1h       60          212     -50.882  -31.795
B-C  9:15    9:45   34m      34          148     -28.833   18.017
C-D  10:02  10:58   56m      56           32      47.49    29.675
D-E  11:10  13:18  2h15m    135          148    -114.486   71.539
E-F  13:25  15:00  1h45m    105           32      89.045   55.641
F-G  15:15  16:19  1h4m      64           90        0        64
G-H  16:35  17:35   1h       60          212     -50.882  -31.795
----------  -----  -----   ------     ------    --------  -------
H-A  18:00  21:26  3h26m  <206.17>   <301.76>   -108.548  175.282
|                                                               |
 ---------------------------------------------------------------

So  the  pilot  knows  his estimated time of arrival  is  in  206
minutes,  or  3  hours,   and  26 minutes,  on bearing 301  degs.
That means he'll arrive  at  the heliport sometime around 9:26 at
night.... Another long day...




















Example 4:
                         * E
                        / \
                       /   \
                      /     \
                     /       \     Mountain
                 F  /  Hill   \ D
                  (*)         (*) ---------* C
                                    Big   /
             Forest                Rock  /
                                        /
                                     B /
                                      *   Forest
                                      |
                                      |
                                      |
                                      |
                                   A (*)

In this example, let's say my Troop is  camping in spread-out Low
Impact sites,  at  several locations this evening, (A) (D) & (F).
If a buddy and I wish to go visiting this afternoon, we'll remain
safest  if we keep track of our locations as we go.  That way  we
can find our way back in the  dark if need be.

As we head out on bearing A-B, my buddy shoots the angle with his
compass  and finds that it is due north.    This is marked on his
paper...

 ---------------------------------------------------------------
|                                                               |
                r Yards   Q degrees      x          y
           A-B     ?         <0>         ?          ?
           B-C....
|                                                               |
 ---------------------------------------------------------------

As we get to point (B), we mark how far we have traveled  on
line (A-B). Say we traveled 200 yards to point (B).

 ---------------------------------------------------------------
|                                                               |
                r Yards   Q degrees      x          y
           A-B   <200>        0          ?          ?
           B-C...
|                                                               |
 ---------------------------------------------------------------











And at the same time we shoot a new bearing to point  (C),  which
happens to be circumnavigating around "Big Rock" outcropping. The
compass Bearing is 32 degrees. We write this down too.

 ---------------------------------------------------------------
|                                                               |
                r Yards   Q degrees      x          y
           A-B    200         0          ?          ?
           B-C     ?        <32>         ?          ?
           C-D ....
|                                                               |
 ---------------------------------------------------------------

Every  time  we change direction we,  write down how far we  came
and the new bearing to the next landmark.   By the time we   make
it to camp (F), our chart looks like:

 ---------------------------------------------------------------
|                                                               |
                r Yards    Q degrees     x          y
           A-B    200          0         ?          ?
           B-C    250         32         ?          ?
           C-D    300        270         ?          ?
           D-E    300        328         ?          ?
           E-F    300        212         ?          ?
           ----------------------------------------------
           F-A     ?          ?          ?          ?
|                                                               |
 ---------------------------------------------------------------

At   camp (F) we take a moment and calculate our way back to  our
own tent site (A). First we figure for x and y :

Where:        x =r*(cos*Q)     y =r*(sin*Q)

 ---------------------------------------------------------------
|                                                               |
                r Yards   Q degrees      x          y
           A-B    200         0      < 200    > <   0     >
           B-C    250        32      < 212.012> < 132.479 >
           C-D    300       270      <   0    > <-300     >
           D-E    300       328      < 254.414> <-158.975 >
           E-F    300       212      <-254.414> <-158.975 >
           ---   -----     -----     ---------- ----------
           F-A     ?         ?           ?          ?
|                                                               |
 ---------------------------------------------------------------






·
(continued next message)

------------------------------------------------------------------------------
 Date: 01-01-94 (16:00)             Number: 2508          Message    8 of   11
 From: Tom De Luca                  Refer#: 0
 To:   DAVID CHESSLER                Recvd: No (PVT)
 Subj: Map & Compass Ver 4.0          Conf:   11 ■ Private Email
------------------------------------------------------------------------------

 @FROM   :UUNET!COMPUSERVE.COM!73521.3453
· (Continued from last message)






Then the x and y columns are totaled.

 ---------------------------------------------------------------
|                                                               |
                r Yards   Q degrees      x          y
           A-B    200         0        200          0
           B-C    250        32        212.012    132.479
           C-D    300       270          0       -300
           D-E    300       328        254.414   -158.975
           E-F    300       212       -254.414   -158.975
           ---   -----     -----     ---------- ----------
           F-A     ?         ?        <412.012> <-485.471>
|                                                               |
 ---------------------------------------------------------------

I  can  tell right off the bat,,that the direction  we  will   be
traveling  in  is  going to be in a   South  Easterly  direction,
because of the polarity of x and y.

                             North
                               |
                        x- y+  |  x- y-
                               |
                   West -------*------- East
                               |
                        x+ y+  |  X+ Y-
                               |      *
                             South

Then I calculate for Q degrees, and r distance:

Where:     Q = Arctan( y/x )

Then...

 Q= Arctan(-485.471/412.012) = Arctan(-1.1782) = -49.679 degrees


Now because x is positive,  and y is negative,  I need to add  or
subtract  180 or 360 to get the correct answer for that corner of
the compass.
                            -49.679
                           +180.
                           --------
                     Answer 130.32 Q degrees













And Where:           ________
                 _  / 2    2
             r =  \/ x  + y


Then....  ___________________        ___________________
      _  /      2          2     _  /
   r = \/412.012 + -485.471   =   \/169753.89 + 235682.09  =

                     ________
                 _  /
                  \/405435.98  =  636.73 yards



So the completed chart looks like:

 ---------------------------------------------------------------
|                                                               |
                Yards   Q degrees      x          y
           A-B   200        0      200          0
           B-C   250       32      212.012    132.479
           C-D   300      270        0       -300
           D-E   300      328      254.414   -158.975
           E-F   300      212     -254.414   -158.975
           ----------------------------------------
           F-A  <636.7>  <130.32>  412.012   -485.471
|                                                               |
 ---------------------------------------------------------------

And  we know that if we walk 640 yards at 130  degrees,  well  be
able to sleep in our own tent.


Tom De Luca
[phone]














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