One of the difficult problems in connection with the design of buildings in congested or closely built tip blocks is to provide light and air for the rear rooms. To obtain a suit able circulation of air is even more trouble some than to secure light. A method adopted with great success for securing the direct cir adopted, thus making an interior plot of this width and about 100 feet in length, the interior being enclosed and used as a playground for the children residing in the block and provided with simple playground equipment.
Following the practice in Europe, American cities, such as New York, Washington, Balti more, Los Angeles, Seattle and Boston have adopted zone or districting systems for dividing the city according to the purposes for which the different sections are best adapted or are already used. This establishment of the zone system is of as much importance in the older cities as in those under development. The num ber of zones depends largely on the activities of the city and on the extent to which the citizens are willing to submit. Those of European cities are much more numerous than would he practicable in America. For example, Karlsruhe, a city of 150,000 inhabitants, has as many as 16 different zones, while American cities have ordinarily adopted from four to six zones for their purposes. The following is a workable basis for the extension of the system in the ordinary American city: (1) Residential district, (a) light traffic, no stores; (b) medium traffic, stores; (2) Business district, (a) me dium traffic; (b) heavy traffic; (3) Industrial district, (a) 25 to 100 employees per establish ment; (b) over 100 employees per establish ment; (4) Tenement district, stores and heavy traffic; (5) Warehousing district, heavy traffic. Other articles on city_planning will be found under GARDEN CITIES, CENTRES.
General: 'Select List of Works Relating to City Planning and Allied Subjects' (New York Public Library, New York 1913) ; Maltbie, M. R., 'Civic Art in Northern Europe' (New York 1903) ; Weber, A. F., 'The Growth of Cities in the Nineteenth Century' (New York 1899). United States: Burnham, D. H., and Bennett, E. H., Plan of Chicago' (Chicago 1909) ; 'Efficiency in City Planning' (New York 1913) ; 'Engineering In terest in City Planning' (in Engineering Rec ord, New York 1913) ; Ford, F. L., 'The Group ing of Public Buildings' (Hartford 1904) ; Ford, G. B., (Digging Deeper into City Planning' (New York 1912), and 'The City Scientific' (New York 1913) ; Koester, F., 'American City Planning' (in American Architect, New York 1912-13) • Lamb, C. R., 'The Possibilities of the lEsthetic Development of Our City' (New York 1909) ; Marsh, B. C., 'An Introduction to City Planning; Democracy's Challenge to the American City' (New York 1909) ; Nolan, J., (Comprehensive Planning for Small Towns and Villages' (Boston 1912) ; Olmsted, F. L.,
'City Planning' (Washington 1910) ; Pray, J. S., and Kimball, T., 'A City-Planning Classifi cation' (Harvard University Press 1913) ; Rob inson, C. M., (The Improvement of Towns and Cities; or, The Practical Basis of Civic /Esthetics' (New York 1901), and 'Modern Civic Art; or, The City Made Beautiful' (New York 1903) ; Wacker, C. H., 'Chicago; A City Set in a Garden' (in Municipal Engineering, Indianapolis 1913), and 'Manual of the Plan of Chicago' (Chicago 1912) ; Zueblin, C., 'American Municipal Progress; Chapters in Municipal Sociology' (New York 1912). Aus tralia: 'Sites for the Seat of Government' ( Report of Royal Commission, Melbourne 1903). Austria: Roessler, A., (Von Wien und semen Garten) (Vienna 1909). Canada: Maw son, T. H., and Vivian, H., Planning and Housing' (Calgary 1913). England: Adshead, S. D., 'Civic Design' (Liverpool 1909) ; Bentley, E. G., and Taylor, S. P., ing, Town Planning, etc., Act, 1909' (London 1911) ; Casson W. A., (The Housing, Town Planning, etc., Act, 1909' (London 1912) ; Cul pin, E. G., (Garden Cities and Town Planning Association' (London 1910) ; Garden City As sociation, (Town Planning in Theory and Prac tice' (London 1907) ; Geddes, P., Devel opment ; A Study of Parks, Gardens and Culture Institutes' (Edinburgh 1904) ; Glen, R. A., and Dean, A. D., Law and Practice of Town Planning' (London 1913) ; Mawson, T. H., 'Civic Art ; Studies in Town Planning, Parks, Boulevards and Open Spaces' (London 1911) ; Royal Institute of British Architects, (Town Planning Conference) (London 1910) ; Triggs, H. I., (Town Planning; Past, Present and Pos sible' (London 1909) ; Unwin, R., (Town Plan ning in Practice; An Introduction to the Art of Designing Cities and Suburbs' (London 1911). France: Gaudet, J., 'Elements et the orie de l'architecture' (in Librairie de la con struction moderne, 4 vols., Paris 1909); Smith, E. R., (Baron Haussmann and the Topographi cal Transformation of Paris under Napoleon III' (in Architectural Record, New York 1907-08). Germany: Eberstadt, R., Studien fiber Stadtebau und (Jena 1912) ; Jones, P., 'Town Development in Germany and Austria' (Birmingham 1911); Howe, F. C., (City Building in Germany' (Bos ton 1912) ; Rehorst, K., (Alte Stidtebilder und moderner Verkehr> (Mannheim 1907); Wolf, G., schone deutsche Stadt> (Munich 1911) • (Brix, J., and others, 'Grundplan fir die Bebauung von Gross-Berlin' (Berlin 1911); Keller, K., and Nitze, P., bau liclie Zukunft, Vorschlige zur Reform der Bebauungsbestimmungen' (Berlin 1910); Was muth, E., (Wettwerb Gross-Berlin 1910; Die preisgekronten Entwiirfe mit Erliuterungi Berichten) (Berlin 1910) ; (Wettbewerb zur Erlangung eines Bebauungsplanes der Stack Dusseldorf' (Dusseldorf 1911). India: 'Re port of Delhi Town Planning Committee, East India' (3 vols., London 1913).