Comparing maps and images Example 1

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Using maps and images
North Downs at OS 1:25,000
Explorer map No 171
Figure 1 Old Quarries at GR
TQ444569 ( map centre)
North Downs at OS 1:50,000
Landranger series
Figure 2 Map centred at GR
TQ444569
Note the changes in colour, area and size of symbol
between the two maps. Can you find Pilgrim House?
Images produced from the Ordnance Survey Get-a-map service. Image reproduced with kind permission of Ordnance Survey and
Ordnance Survey of Northern Ireland.
What kinds of
features can you
recognise in
each view?
Aerial view of the North
Downs near Pilgrim House
www.multimap.com
View East to Pilgrim House
http://www.geograph.org.uk/photo/64476 © Pip Rolls
Notes
• Two map extracts are used. Fig 1 centres on kilometre square [Grid
Reference TQ4456] and shows the chalk escarpment east of Westerham Hill
which has still a good cover of mixed woodland, scrubland and steep grassy
slopes.
• Go to http://getamap.ordnancesurvey.co.uk/getamap/frames.htm
• Enter the Grid Reference (GR) TQ4456 into the Get-a-map search box and
the same map will come up on screen. This is at the largest scale 1:25,000
and is represented by the large + in the diagram to the left of the map on
screen. Click on the circle below the + and the map shown in Fig 2 comes
on screen This shows a larger area but fewer details and is the LandRanger
scale of 1:50,000.
• The Explorer series shows all paths, roads, boundaries, specific vegetation,
accurate spot heights and building detail. This is at the 1:25,000 scale. [NB
the maps shown at this scale on other map sites such as Multimap and
Streetmap use the OS conventions from the Landranger series - Compare
Figures 1 and 2]
•
•
Copyright : Copies of Get-a-map mapping for teaching and classroom use:
Educational establishments may download sufficient copies of each map image as
displayed on your browser to provide each pupil/student and teacher with an
individual copy.(See http://www.ordnancesurvey.co.uk/oswebsite/getamap )
The aerial photographs are obtainable on the Multimap site
(http://www.multimap.com/map/home.cgi)
Maps and aerial views of a limestone area
The Mendips : Cheddar Gorge
The whole grid square
reference (GR) is ST4654
This is the four figure
reference for the bottom,
left hand (SW) corner of the
full square in the centre of
the extract and this is the
GR needed to enter in the
search box in any map
website.
[If you are unsure about
Grid References (GR) go to
OS National Grid PDF]
OS 1: 25,000 from Get a map Centre of map at GR ST462543 GB
Images produced from the Ordnance Survey Get-a-map service. Image reproduced with kind permission of Ordnance Survey and
Ordnance Survey of Northern Ireland.
The quarries In the Mendips are large and cut into the crystalline Carboniferous
Limestone which is very hard ! The quarries and rock cliffs are shown by the
rock cliff symbol rather than the steep slope symbol which is used for the softer
limestone quarries on the Chalk hills. [ See OS Legend Explorer and OS
Legend Landranger symbol guides]
What
symbols
might you
want to use
if you were
mapping
this area?
What features can you
recognise?
Aerial view Cheddar, Cheddar Gorge and adjacent quarries 1:50,000 Source Multimap.
http://www.multimap.com/map/photo.cgi?client=public&X=347000.076556189&Y=154000.891159618&scale=25000&width=700&heig
ht=400&gride=346261.076556189&gridn=153967.891159618&lang=&db=freegaz&coordsys=gb
Thinking about symbols
• What activities do you OR would you like
to do in your spare time?
• List some activities and hobbies with a
partner
• Use the symbol guide to find something to
represent your chosen activity – can you
find this on a local map? If you can’t find a
relevant symbol can you design one?
Which symbols would
you be looking for?
What symbols did
you have to design?
Challenge: working with a partner, you have just five minutes to
draw all the water features you can think of.
Here are some reminders:
Marsh, weir, salting, lighthouse, shingle, beacon, lock, cliff, towpath,
aquaduct, footbridge, canal, mud, sand, dunes, slopes, flat rock,
How many did you get?
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