Where contour lines are close together, elevation is changing rapidly in a short distance and the terrain is steep. To determine elevations, pay attention to the amount of space in between lines. To avoid the map being cluttered with numbers only index contours are labelled with height values. To make topographical maps easier to read, every fifth contour line is darker and wider in colour. However contour lines are usually drawn at 10 metre intervals on a 1:50,000 scale map and at 5 metre interval on a 1:25,000 scale map. Different maps use different intervals depending on the topography. For example, if your map uses a 10 metre contour interval, you will see contour lines for every 10 metres of elevation – lines at 0, 10, 20, 30, 40 and so on. We call the spacing between contour lines the contour interval. The change in elevation from one contour line to the next is always the same within the same map. Such maps with contour lines on them are called topographical maps. In fact these lines are very useful because they illustrate the shape of the land surface or its topography on the map. These videos will help us understand what contour lines represent and how useful they are to interpret relief of the land.īesides height above sea level contours also show the shape of the terrain. Topographical maps and contour lines can present a major challenge to understand. Image 1 shows how cartographers (map makers) managed to devise an ingenious way to show three-dimensional topography on a two dimensional flat surface with the use of contour lines. If on the other hand the numbers associated with the contour lines are decreasing, there is a decrease in elevation. If the numbers associated with specific contour lines are increasing, the elevation of the terrain is also increasing. Thus a contour line with a 60 metres marking indicates that any place along that contour line is 60 metres above sea level. If you were to walk the path of a contour line in real life, you would remain at the same elevation the whole time, never travelling up and down. Contour lines show height of the ground above mean sea level (MSL) in metres. Sand paper and paint for bases.Contour lines are imaginary lines drawn on Ordnance Survey maps connecting points of equal elevation and are used to illustrate relief on a map. Wire, Coat hangers, telephone wire, Pliers, Beads, blocks of wood, drill, drill bit. Had them cut the coat hanger into one length and bent it to their desire, then they took the telephone wire and started to weave, curl and whatever. We took a wooden block (scrounged from construction sites), drilled two holes in it, the size to accommodate a wire coat hanger.
This could be a lesson for a fantasy tree - Foil tooling could be added.įrom Christa-Maria: I Also got a box of Twisteez Wire that was color coded and had them make sculptures. Grade Level: middle school (adaptable to other grades)ĭrill hole in wood scarp bases for telephone wire - Insert wire and bend to interesting shape. I kind of let them do their own thing and they came up with wonderful stuff - lots of line figures, animals, I was enchanted by their creativity.Įlizabeth Berrien - Wire Sculpture - See Teaching pages and Workshops. That in itself was fun to work with and when I brought the wire and pliers to school, the kids did not wait for instructions, but started to play. When I first taught about wire, I got a donation of all kinds of different wire from a wire company, we used to have nearby.
Students draw contour line drawing (suggestion of animals and people)
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