AgendaAgenda

►This week:This week: Map and compass practicumMap and compass practicum Field mapsField maps

►Walk and estimate distancesWalk and estimate distances Add bearings, scaleAdd bearings, scale

SamplingSampling Sampling statistics: Why randomness?Sampling statistics: Why randomness?

Compass and MapCompass and Map

Field walking and Field walking and

orienting site features.orienting site features.

Before you beginBefore you begin

►You need to know your stride lengthYou need to know your stride length Set up a 100 ft tape and walk from 0 to 100 Set up a 100 ft tape and walk from 0 to 100

feet in a natural stride while counting steps.feet in a natural stride while counting steps. Repeat 4 timesRepeat 4 times Add up the number of steps for all 4 trialsAdd up the number of steps for all 4 trials Divide the number of steps into 400. This is Divide the number of steps into 400. This is

your average stride length. You can now your average stride length. You can now estimate distance by counting strides.estimate distance by counting strides.

How might this vary with terrain?How might this vary with terrain?

To orient a compassTo orient a compass

►We will use a handy web site for We will use a handy web site for compass preparation.compass preparation.

►Remember: the red arrow always Remember: the red arrow always points to magnetic north, not in the points to magnetic north, not in the direction you want to go.direction you want to go.

►The degree plate on a compass will The degree plate on a compass will turn to allow you to make measures or turn to allow you to make measures or set a bearing.set a bearing.

Useful websitesUseful websites

►http://www.buckskin.org/Resources/Ouhttp://www.buckskin.org/Resources/Outdoor/compass1.htmtdoor/compass1.htm

►http://www.scoutbase.org.uk/library/http://www.scoutbase.org.uk/library/hqdocs/facts/pdfs/fs315074.pdfhqdocs/facts/pdfs/fs315074.pdf

To follow a courseTo follow a course

►Find north, line up the needle and the Find north, line up the needle and the arrow at 0/360 degreesarrow at 0/360 degrees

►Turn toward the direction you want to Turn toward the direction you want to go. Realign the arrow on the plate with go. Realign the arrow on the plate with the needle.the needle.

►Read the degrees that now are Read the degrees that now are showing at the top of the compass.showing at the top of the compass.

Phase I survey: Walking a compass transect. Line-of-sight.

Continuing on courseContinuing on course

►Make a line of sight reading on a Make a line of sight reading on a distant feature. As long as the needle distant feature. As long as the needle stays aligned with the arrow and you stays aligned with the arrow and you aim at your distant line-of-sight target aim at your distant line-of-sight target you will be on course.you will be on course.

►To change course you can again turn To change course you can again turn the plate to a new heading or to a the plate to a new heading or to a specified bearing. Sight on a new specified bearing. Sight on a new feature and proceed.feature and proceed.

To determine an alignment of a To determine an alignment of a feature, such as a building.feature, such as a building.

►Orient yourself in such a place that will Orient yourself in such a place that will allow you to look along the feature’s allow you to look along the feature’s axis. axis.

►Align the compass so that the long edge Align the compass so that the long edge is parallel to the feature.is parallel to the feature.

►Adjust the arrow plate until it is aligned Adjust the arrow plate until it is aligned with the north arrow.with the north arrow.

►Read the degrees (your bearing) from Read the degrees (your bearing) from the scale at the top of the compass.the scale at the top of the compass.

Compass and topo mapCompass and topo map

►Reading a topographic mapsReading a topographic maps►Understanding landform features and Understanding landform features and

landscapelandscape►http://egsc.usgs.gov/isb/pubs/http://egsc.usgs.gov/isb/pubs/

booklets/symbols/booklets/symbols/

Compass courseCompass course

►Follow compass bearings and Follow compass bearings and distances from station to station to distances from station to station to retrieve tags. retrieve tags.

►At each station there will be new At each station there will be new bearings given to the next station.bearings given to the next station.

►Use pacing to determine distances.Use pacing to determine distances.►Hand in all tags at completion of the Hand in all tags at completion of the

course.course.