When placed in charge of the Mortgage Department of the U. S. Mortgage & Trust Co. in 1895, the writer searched in vain, both in England and this country, for books on the science of city real estate as an aid in judging values. Finding in economic books merely brief references to city land and elsewhere only fragmentary articles, the plan arose to outline the theory of the structure of cities and to state the average scales of land values produced by different utilities within them.

The material for this study of the structure of cities - including their locations, starting points and lines of growth - has been gathered from a large number of local histories of American cities, old maps, commercial geographies, etc.

The material for the study of average scales of values has been drawn from the mass of valuations of land and buildings, rentals and mortgages, obtained in about fifty cities in the course of the mortgage business of the U. S. Mortgage & Trust Co. and also from many visits to these cities.

The viewpoint is that of a conservative lender on real estate and while the examples cited are chiefly from the smaller cities, it is believed that the. principles stated are universal and differ only in application and in resulting combinations.

Special acknowledgment is due for aid in figuring the structural and commercial value of buildings and in the preparation of maps, to Cecil C. Evers, late member of the American Institute of Architects.