Compass The Silva compass The protractor type compasses such as those made by Silva are light, reliable and accurate for mountain navigation and with their see through base plate are ideal when used in conjunction with the map. Its main features are:-
• The compass dial is a 360° pro-
tractor used for calculating angles known as bearings Setting a map by compass In bad weather or in unfamiliar or featureless country, using a compass is the only reliable way to set your map. Again, the purpose is to orientate the map so that it coincides with the countryside around you and will make route finding and feature recognition easier. To do this, simply place the compass on the map and, while holding it flat, turn both the compass and the map until the red end of the magnetic needle points to north on the map. The map is now set.
• Measurements for calculating distance on the map.
• Parallel orienting lines and orienting
arrow used to align the compass dial with the North - South grid lines on the map when getting a bearing.
• The magnetic needle
The red end points to magnetic north
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Roamers for several scale maps used to help give accurate grid references.
TIP • Your compass should be attached to your jacket or rucksack on a boot lace, long enough to allow you to use the compass with the map to calculate a bearing. • When using your map and compass out in the open, get down on your hunkers and shelter it from the wind.
Direction of travel arrow points the way you have to go when following a bearing. Magnifying lens to help with map detail. Index Marker (where the tail of the direction of travel arrow cuts the dial). This is where you read your 109
