Longitudinal strips at 15 degree intervals are allocated a letter, starting with A for the strip between 180 W and 165 W and ending with Z for the strip between 165 E and 180 E. There are 24 strips and letters I and O are not used.
Latitudinal strips are lettered from A for the strip between the south pole and 75 S, up to M for the strip between 75 N and the north pole. I is not used.
back to Vector Product Format and the Digital Chart of the World