This otherwise ordinary map of the British Empire is identical to scores of others produced during the 19th century except for one thing: it displays 490 degrees of longitude for a 360 degree world. As a result, British colonies in New Zealand, Australia and India are each shown twice, once in the East and again in the West, and the apparent size of the Empire is artificially increased.
On any cylindrical map projection, like the Mercator projection shown here, meridians appear as vertical lines. While such maps customarily show only 360 degrees of latitude, the rectangular shape of the map allows the presentation of more territory -- that is, presenting the same land twice -- without making the distortion obvious. This technique was used repeatedly by Bartholomew: see ID # 1149 (380 degrees); ID # 1130 (400 degrees); ID ## 1101, 1166 (420 degrees); and by others, see ID #2179 (450 degrees).
