The Use of Grid References: Maps and Places

We shall now look at the Maps and Places, with our main focus on the use of grid references.

•A map is a representation of the earth or part of it drawn on a piece of paper, wall plank etc.
•Position of places on the earth’s surface:
• To find a particular place on a map, these must be an accurate method of locating it.
• The accurate method to be used when finding a particular place on a map is the grid reference system
•The grid reference system consists of a series of lines drawn across a map running from top to bottom and from side to side.
•These lines are numbered making it easy to locate the exact place.

How to read grid references in

•The grid lines running from North to South (Top to Bottom) are called Eastings because they represent distances eastwards from the origin.
The grid lines running from West to East (side by side) are called Northings because they represent distances Northwards from the origin.
•When locating a place you have to start with Eastings and then Northings.
•Grid Reference are given in one of two ways:

• Four Figure grid reference: Used to identify a 1km x 1km square
• Six Figure grid reference – Used to identify a location 100m x 100m

Four Figure Grid Reference

•We use a four figure grid reference if we want to identify a large object e.g. a lake
•The four figure grid reference depicts only a general location of the point in the grid square.

•When taking a reading from a grid reference map, you take the EASTING first
•After taking the eastings, NORTHINGS are then read.

EXAMPLES

1.What is the four figure grid reference for station A?

•The EASTING for station A is 71
•The NORTHING for station A is 31
•Therefore the four figure grid reference for station A is 7131

SIX Figure Grid Reference

•The six figure grid reference is used when you want to identify a smaller object inside a square e.g. a stream junction
•A six figure grid reference gives a precise or accurate position of a point in a given grid square.
•We need to subdivide our 1km x 1km square into smaller 100m x 100m squares
•Write down the two figures representing the easting on the immediate left
•Divide the space between the easting in which the point is found into 10 equal lines and mark the lines 1 up to 9
•Write down the line that passes through or on the left of the point next to the first two
digits

•When taking a six figure grid reference, a four figure grid reference is taken first
•Therefore, the six grid reference for point A can be taken in the following steps:

1.The four figures are taken first starting with EASTING and then the NORTHING. 71—30—
2.Then the box is divided into 10 units of Easting’s and Northings
3.write down the line that passes through or on the left of the point next to the first two digits

•Starting with easting first (1) and then the Northing (7).
•Therefore, the six figure grid reference for station A is 711307