ABSTRACT
In practice, only rarely, as in the case of the broad income Class VIII, are the families and houses of one grade. The extent of the difficulty naturally depends on the number and width of grades chosen. There were eight grades of income and five grades of rateable value. In the great majority of streets the families or houses were in several of the grades, often indeed concentrated mostly in three groups, but also widely dispersed through many or all of the grades. How are these diversities to be drawn together into a single impression, to which a single colour could be assigned?
