Flows between 1975 and 1976 drawn between the 97 areas from the national information system, on an equal population cartogram — software by author on an Archimedes computer.
Having lowered the threshold to one tenth of one percent a link has been forged across the centre of the country through Derbyshire. The Tyneside conurbation is now fully interlinked, but Scotland, the Isle of Mann and Northern Ireland are yet to be connected. Almost half of all the recorded migrants are shown, through the streams they were part of.
Fourth print from a series of six.