Quite apart from any change in proportion of population, there is an enormous interchange constantly taking place between adjoining counties and districts.

The general fluidity of population has been of course vastly increased by new facilities of communication and migration; persons are less and less bound down to the village or county in which they were born.

So we find that in England and Wales, only 739 out of each 1000 persons were living in their native county in 1901.

In some London districts it is reckoned that more than one quarter of the inhabitants change their address each year.

So that when we are told that in seven large Scotch towns only 524 out of each 1000 are natives, and that in Middlesex only 35 per cent.