For instance qY 985 613 (somewhere around Carlisle) can also be expressed as 3985 5613. To do this, square vV (the South-West corner of the grid out in the Atlantic) is taken as square zero and then the grid squares are counted from there to the location being referenced. Grid references can also be given in an all numeral notation. For instance, wQ 683 825 is a location in South London. The complete grid reference includes both the grid square letters and the numerical reference giving the location within the grid square. Greater precision can be obtained by using six, eight, or even more digits, but always an even number with the same precision on both coordinates. That is, it is two squares across and seven squares up (counting from zero) from the reference corner. For instance, the grid reference 25 76 refers to a 1 km square within the 10 km square 2 7. These squares are numbered according to eastings and northings, that is, counting from the south-west corner of the 100 km square. Įach 100 km square is subdivided into 10 km squares, and each of these is further subdivided into 1 km squares. For instance, the squares covering London are wL and wQ. #MILIARY GRID MAPPING FULL#The full designation for a grid square is the 500 km letter in lowercase followed by the 100 km letter in uppercase. The 100 km squares are also given letters (with I omitted). Each 500 km square is further divided into 25 100 km squares. Ireland is covered by square I, but the Irish grid is tilted slightly to the East relative to the English grid. The squares covering England are Q, R, V and W with an intersection somewhere between York and Thirsk. The map is divided into a grid of 500 km squares. #MILIARY GRID MAPPING SERIES#Hong Kong, for instance, was surveyed in 1962 for a series of 1:10,000 and 1:25,000 maps of the territory. However, the Cassini Grid system continued to be used to map colonial possessions into the 1960s. Īfter the war, the Cassini Grid system was replaced with the Ordnance Survey National Grid (see § Transition to National Grid). It continued in use until some time after World War II. It may also be referred to as Military Grid, War Office Grid, or Purple Grid (due to the grid colour on some issues of maps). The Cassini Grid system is thus more properly called the Modified British System. It modified and replaced a grid coordinate system first deployed in 1919 known as the British System. It is so called from the use of Cassini map projection. The Cassini Grid system was introduced in 1927 for maps of the United Kingdom for the British military.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |