THE industrial town differs from other towns and the industrial districts of any town differ from its other districts in certain respects. A greater proportion of their area must be given over to the mills, shops or factories where are fabricated the articles which the town or district produces, which have created its prosperity and wealth and which have made it known abroad. When one thinks of Pittsburgh it is in terms of iron and steel and the smoke and grime that always go with their production. Sheffield suggests cutlery; Manchester, cotton goods; Lyons, silk; Essen, ordnance and steel forgings; Grand Rapids, furniture; Minneapolis, flour; Omaha and Kansas City, packing houses and stock-yards. The larger cities have such varied industries that we think only of the great value of their manufactured products and do not identify them with any particular output, yet different parts of these cities are as closely identified with certain industries and activities as are the smaller towns with their one chief product.