You may have seen a compass rose in an old magnetic compass, small or miniature designs of compass rose on digital compasses and they are also used in maps, navigational systems and nautical charts. The concept of compass rose is quite old and it doesn’t really have much significance today since we are mostly relied on GPS systems and digital mapping. But it is a significant element that has evolved with time and still holds the key in analog geographical or navigational charts.
Compass Rose Defined
It has many names. It is also called Rose of the Winds or simply a wind rose. A compass rose is a figure that forms on a compass due to the intersecting lines pointing to different directions. Imagine an old magnetic compass. It has a suspended needle pointing north. You would see the directions laid out at the base. Typically, you would have north, south, east and west. You may also have north east, south east, south west and north west depicted as straight lines bisecting the gap between north and east, east and south, south and west, west and north. These lines form a pattern at the centre. This is known as a compass rose. In colored maps, a compass rose is often decked up with red, black and white. Blue, yellow and other colors are also used widely.
The primary purpose of a compass rose is to make it easy to know the exact direction. One glimpse at the needle reflecting well which direction it is pointing by the virtue of a colored compass rose and you would know which way you are headed.
Types of Compass Rose
The types of compass rose or the exact pattern depend on how many directions the compass is implying or depicting. There are four point compass roses that only point to north, east, south and west. There are eight point compass roses that point to north, north east, east, south east, south, south west, west and north west. There are sixteen point compass roses. Four primary arms point to north, east, south and west. Four secondary arms point to north east, south east, south west and north west. Eight more arms point to north north east, east north east, east south east, south south east, south south west, west south west, west north west and north north west.
Medieval Directions of Compass Rose
In traditional designs, the compass rose had eight directions, pointing to North or known by its traditional wind name Tramontane, North-East or 45° right from north known as Greco or Grecale, East or 90° right from north known as Levante, South-East known as Sirocco, South or 180° from north known as Ostro or Mezzogiorno, South-West known as Libeccio or Garbino, West was referred to as Ponente and North-West was referred to as Maestro or Mistral.