3. Topographical maps
A topographical map shows physical and human features in greater detail.
Interactive for learning map readings:
Click on the link below to mapzone -The Homework Help section includes interactive tutorials and quizzes for students to independently learn about map-reading skills. Includes skills such as reading bearings, grid-references and compass-directions. http://mapzone.ordnancesurvey.co.uk/mapzone/index.html
Try out this simple excercise/game on topographical map:
Notes on topographical map reading:
• Use four-figure and six-figure grid references.
1. Always remember to read from the bottom left corner.
2. If the question ask for the four-figure grid reference or grid square of a particular building, e.g. the Hindu temple shown in Fig 1. Read the number for the Easting first (from the X axis) and then the Northings (from the Y axis). E.g example in Fig.1 is located in 2672
3. If the question ask for the six-figure grid reference or grid square of a particular building, e.g. the Hindu temple shown in Fig 2. Start by finding the grid square with the feature, then divide the grid square into 10 equal parts along both the Northings and Eastings. Place a ruler onto the bottom left corner of the feature, e.g. the Hindu temple is located at 266727. Read the number for the Easting first (from the X axis) and then the Northings (from the Y axis).
Use cardinal points (i.e. North, South, East, West) for compass direction
To measure the direction of one point to another, draw a straight line connecting them.
Read the question carefully– if the question ask you the direction of B from A, then draw a + sign at A and read the direction from A.
• Use compass bearings.
Draw a straight line connecting the 2 points.
Draw a + sign at where you are taking the bearing from.
Place the protractor at the + sign with 0° facing north and then read the bearings from the point starting from 0° (north) clockwise as shown in Fig.4
Try it out! Practice reading the bearing below.
1. Check the box next to "Use Protractor" so that the protractor will appear.
2. Read the question on where to measure the bearing from.
3. Select "Move compass to A or B" as shown in question. E.g. point B
4. Drag the protractor and rotate it so that O points to the north.
(If the angle is more than 180° then rotate the protractor with 0 starting from South and the read the angle. Add 180°to the reading.)
5. Drag the pin head so that the line intercept with the point it is measuring to e.g.point A
6. Read the angle from the protractor and enter the number into the keypad with the degree symbol.
7. Click on "Enter Check".
• Use symbols in a legend to locate and describe features on maps.
Do note that abbreviation symbol can be used to represent a point so it can also be classified as a point symbol. This is similar for trigonometrical station and spot height. Though they are height symbols they can be classified as point symbols. Contours can be classified as a line symbol.
Contour lines are lines which join points of same height and it can be used to show the relief of an area.
Settlement Patterns
a) Dispersed – houses far apart – areas with low economic development e.g. normadic herding, smallholdings
b) Linear – arranged in a line, usually along a mode of transport ( rail, road) or waterway (river, coast) to take advantage of the accessibility and resources.
c) Nucleated – concentration of buildings or houses – usually at road junctions or centers of economic activities ( e.g. community or village with facilities like school and shops)
Map Scale
a) Linear scale
4 cm on the map represents 1 km
Thus every cm on the map represents 0.25km
b) Statement Scale
1:25 000
1 cm represents 25000 cm = 1 cm represents 250m or 1 cm represents 0.25km
Measuring straight-line distances
Use a ruler to measure the distance between two features on a map
Then, using a statement scale, multiply the measurement on the ruler with the actual distance that it represents
Alternatively, a linear scale can be used to measure the straight-line distance
