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Map Reading X marks the spot… By Sergeant Greensill Why do I need to know how to map read? Within Cadets -Duke of Edinburgh Award -Field Craft Training -Classifications within cadets Out Of Cadets -Geography (and basic Maths) In School -Driving -Finding your way around in general (so you don’t get lost.) What is a map? -A Map is a birds eye view of the surrounding area to help guide us from one place to another. -It includes lines of Longitude -And Line of latitude Lines of Longitude The POLES DO NOT ROTATE The prime Meridian runs NORTH TO SOUTH THROUGH GREENWICH A line of Longitude is also referred to as a Meridian • Lines of Longitude run parallel to the Prime Meridian at Greenwich Lines of Latitude • Lines of Latitude run parallel to the Equator Co-Ordinates Across the hall and up the stairs 1:50000 4 figure grid reference of A =(13,34) To find a four figure grid Reference, you need to Locate the bottom left corner (the SW corner of the square) that A is in. A is 13 across, and 34 up. 1km Co-Ordinates Across the hall and up the stairs 1:50000 6 figure grid reference of A=(13?34?) To be more precise in mad reading, we need to be able to use 6 figure grid references, so we break the box into 100 squares. 1km Co-Ordinates Across the hall and up the stairs (on a real map, symbols are smaller, so they are more accurate then our map, hence the 35 remarked A) 9 To work out your 6 figure grid reference work from the bottom left hand corner 8 of the large square. For your first 3 digits take the start number 7 going across (13) and place a number 6 from 0-9 (depending on the positioning 5 of the feature) to the end of our first 2 digits. E.g. 135 34? 4 For the second 3 digits take the first 3 3 digits, then the start number going up (34) and place a number from 0-9 2 (depending on positioning) to the end 1 of the end of our second 2 digits. E.g. 135 345 34 0 13 A 1 2 3 4 5 6 7 8 9 14 Co-Ordinates Across the hall and up the stairs So to find A, we went 13 and 5 minisquares across (135), and then 34 and 35 5 mini squares up (345). 9 So the 6 figure grid reference of A would 8 be 0.1km 7 6 135345 A 5 4 3 2 1 34 0 13 1 2 3 4 5 6 7 8 9 14 The key Just like a key to a door, the key on a map helps you to unlock the information stored in the colours and symbols on a map. The key will help you to identify types of boundaries, roads, buildings, agriculture, industry, places of interest and geographical features. Scale The scale is very important. It helps you find the size, height and dimensions of the features shown on a map. Explorer maps are 1:25,000 (1 cm = 250 m). These are useful for walking and other outdoor pursuits. This is the type we use for D of E. So for every 1cm on a map, its 250m. So 4 cm is 1km. M726 Map -It is a 1:50,000 map So for every 1cm on the map, you are looking at 500m. Every grid square on an M726 map is 2cm by 2cm, So how big is one square? Each Square is 1km. - This map is TEPOGRAPHIC meaning that the map shows the shape and surface detail of the land. This includes natural and man-made features. Using a Compass This is why we use degrees of travel (bearings). 360° 0° 90° 270° For this reason we break it down into 16 directions of travel, but still this isn’t very accurate when reading a map and you’re trying to get somewhere specific When referring to a compass directions you will already know that the compass can be broken up into Directions..e.g North, South, East and West This is only accurate to four directions of travel 180° Using a compass What’s the point? It just points north… A compass can help you find your way as it can be used to set BEARINGS. You set a bearing so that you can travel from one place to another, and is useful to check you are travelling in the right direction. Contour Lines -A contour line is a reddish brown line drawn on the map joining all points of equal height above mean sea level (MSL) -Each line is a 10 metre interval on the M726 series. -The closer the lines are together, the steeper the gradient (either up or down) -1:1 is a steep gradient -1:20 is not so steep -If there are many line together at the base of a slope, we say the shape is convex 50