Computer disks map the world

A DETAILED atlas of the world squeezed onto four disks has just been published for pounds 200. Used with a CD-Rom player, the disks allow a personal computer screen to become a window on to the atlas, which can be scrolled all round the world and zoomed in and out, adding or removing detail to taste, writes Andrew Brown.

The Digital Chart of the World is based on the 1:1,000,000 air charts produced by the US Defence Mapping Agency, which, unlike Ordnance Survey, is forbidden to copyright its products, accounting for the low price of the digital version.

Chadwyck Healey, the Cambridge academic publisher that is selling the CDs, expect that it will be useful to companies as a source for their own maps.

Because the maps are digitised, they can be customised to taste: it is possible to print out a map that shows only roads but no rivers, or vice versa, and users can add their own detail, positioning sales forces or armed forces where they are needed.

The software is the first to use Vector Product Format, a new convention for the representation and display of mapping information, which the manufacturers hope will become an international standard, enabling maps from different sources to be combined.

Digital Chart of the World; Chadwyck-Healey, Cambridge Place, Cambridge CB2 1NR; pounds 200.