Numbers used to show the MAP position of a point?

Answer 1

The Army uses two types of Numbers used to idenify a point on a map. Hill Location All military maps use contours lines to show elevation in Meters. Even US maps use meters for elevation. The highest eleveation of a Hill was noted by a triangle with a peak elevaltion. So it was easy to refer to the hill by it's elevation. So, "Hill 803" would be a hill with an elevation of 803 meters---that is if you are using the correct map. Map Coordinates Civilian maps used the global map coordinates of Lattitude and Longitude that is measured in Degrees, Minutes and Seconds. This is quite difficult to use. Military maps have a grid overlayed on top of the map. The Army would divide a country into grids and number them(British maps used letters to identify the grids). Each of these Map Sheets were further divided into 4 sub-divisions and these were further sub-divided and then one more sub-division. The top Map Sheet was usually printed in 1:100,000 scale. Each sub-division was smaller scale: 1:50,000 then 1:25,000 and down to 1:12,500. And the smaller the scale the more details were included in the map. Now the Map Sheets had a grid coorinates identified. This allowed a point on the map to be located using 6 digit number, such as 468-325. This number is the values to plot the point like you would in Geometry using X-axis and Y-axis. The first number(468) is read horizontally and the second number (325) is measured vertically to locate the point. A grid box, identifed between 2-digit numbers such as 46 to 47 was exactly 100 meters. So the grid is easy to use and estimate distances---compared to using degrees and minutes. In this example, the map will only have 2-digit coordinate values. So you read the X-axis to located grid lines 46 and 47. The x-value 468 will be estimated by dividing the grid into 10 segments and to locate 468. Then read the vertical grid to 32 and 33. Value 325 will be half way (or 5/10) between the two grids. Grid Coordinates were used to identify position of friendly troops and enemy fortifications. It was important to identify the Map Sheet that you were using. This was because the grid coordinates would repeat every 100Km. The top map sheet was identified by a number such as Sheet 34. The map of lower scale was identified with Roman numbers such as Sheet 34-I and Sheet 34-IV. The next four sub-divisions were identified by Letters NE, NW, SE, SW; so it would reference Sheet 34-III-NE. The next lower scale was identified with sub-letters such as Sheet 34-III NE(a). Modern GPS The modern army uses Global Positioning System(GPS) for locating positions.