Map Reading Skills
1. Reading Grid References
a.Four-figure grid reference
Identify how a post office is represented on the map by reading the legend.
Look at the map and locate the grid square where the post office is found.
Read the easting (two figures – 10) and the northing (two figures – 37) that intersects at the bottom left corner of the grid square.
The four-figure grid reference is 1037.
b.Six-figure grid reference
Repeat steps 1, 2 and 3 of reading a four-figure grid reference.
Divide the space between the two eastings (08 and 09) into 10 equal parts. Number the parts 1 to 9.
Divide the space between the two northings (36 and 37) into 10 equal parts. Number the parts 1 to 9.
Locate the small square where the school is found.
Read the easting (three figures – 080) and the northing (three figures – 365) that intersect at the bottom left corner of the newly divided grid square.
Six-figure grid reference
The six-figure grid reference of the school is 080365.
Note: If the feature is very large, it is acceptable to accept any six-figure reference that lies within the boundary of that feature
2.Measuring Distances
a.Straight-line distance
To measure the straight line distance between the post office and school:
Locate the road (or feature) you wish to measure.
Place a piece of paper between the given points. Mark out their position at the edge of the piece of paper.
Put the paper on the line scale of the map.
Adjust your paper to read off the answer (if necessary).
Express your answer either in km or m.
b.Curved distance (using a string)
1.Locate the road you want to measure on the map.
2.Place a piece of string carefully along the road.
3.Mark the starting point of your measurement on the string.
This is step 2 even though the label is step 3 in the diagram.
This is step 3 even though the label is step 2 in the diagram.
4.Place the string along the line to be measured and mark the ending point.
5.Straighten out the string.
6.Move it to the line scale on your map and work out the distance.
3.Finding Direction and Bearing
a. Direction
The direction of one place to another can be determined by using compass points.
The main points are north, south, east and west.
The other points are northeast, northwest, southeast and southwest.
For more accurate directions, further divisions are made between the compass points.
Always take note of the key word ‘from’ in the question.
The location that comes after this word is where you begin your measurement.
If you are required to measure the direction of the post office (101376) from the school (080365):
Locate the school and the post office using the grid references given.
Draw a grid north arrow at the centre of the school.
The vertical line must be parallel to the easting and the horizontal line to the northing.
Draw a line to connect the centre of the arrow to the center of the post office.
Determine the direction assuming the top of the map is always the grid north.
The direction of the post office from the school is east-northeast.
b.Compass Bearing
They are measured in degrees clockwise from 0° to 360°.
To measure the bearing of the school from the post office:
Repeat steps 1, 2 and 3 used for the measuring of directions.
Using a protractor, place the 0° on the right side of the grid north arrow and read clockwise to obtain the grid bearing.
If it is more than 180°, the protractor must be placed on the left side of the grid north arrow.
The compass bearing is 243°.
Measuring Gradient
Gradient refers to the steepness of the slope.
Gradient =
Difference in vertical height between two points
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Horizontal distance between two points
The vertical height can be obtained by looking at the value of the spot height, bench mark or trigonometrical station.
You can also derive it by reading the contour lines.
The horizontal distance can be obtained by measuring the straight line or curved distance between the two given points.
Gradients are usually expressed in ratios such as 1:5, meaning that for every 5 units on the ground there is an increase/decrease in height by 1 unit.
To locate the gradient between the school and the post office:
Locate the school and the post office using the grid references given.
Derive the height of both the school and the post office by checking the contour lines.
Calculate the difference in height between the school (50m) and the post office (150m).
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