sentences:  On the plate carrée projection the grid cells appear square, however if the Mercator projection is used, the grid cells appear 'stretched' vertically nearer the tops and bottoms of the map.On the actual surface of the Globe, the cells are approximately "square" only adjacent to the equator, and become progressively narrower and tapered (also with curved northern and southern boundaries) as they approach the poles, and cells adjoining the poles are unique in possessing three faces rather than four.Each 10°x10° square is allocated a number between 1000 and 7817.