Walter Bagehot, _The Postulates of Political Economy_ (London, 1885), pp. 7–8. Footnote 9: Cf. W. I. Thomas, _Source Book of Social Origins_, p. 169. Footnote 10: Charles Horton Cooley, _Social Organization_, p. 15. Footnote 11: Walter Besant, _East London_, p. 13. Footnote 12: William I. Thomas, “Race Psychology: Standpoint and Questionnaire with Particular Reference to the Immigrant and Negro,” _American Journal of Sociology_, XVII (May, 1912), 736. Footnote 13: _Reports of the United States Immigration Commission_, VI, 14–16. Footnote 14: Jacques Loeb, _Comparative Physiology of the Brain_, pp. 220–21. Footnote 15: _Ibid._, p. 221. Footnote 16: James Bryce, _The American Commonwealth_, I, 566. Footnote 17: Sumner, _Folkways_, p. 12. Footnote 18: Cf. Bryce, _The American Commonwealth_, p. 267. Footnote 19: “British Conurbations in 1921,” _Sociological Review_, XIV (April, 1922), 111–12. Footnote 20: See E. H. Shideler, _The Retail Business Organization as an Index of Community Organization_ (in preparation). Footnote 21: For a study of this cultural area of city life see Nels Anderson, _The Hobo_, Chicago, 1923. Footnote 22: Weber, _The Growth of Cities_, p. 442. Footnote 23: Adapted from W. B. Munro, _Municipal Government and Administration_, II, 377. Footnote 24: _Report of the Chicago Subway and Traction Commission_, p. 81, and the _Report on a Physical Plan for a Unified Transportation System_, p. 391. Footnote 25: Data compiled by automobile industries. Footnote 26: Statistics of mailing division, Chicago Post-office. Footnote 27: Determined from _Census Estimates for Intercensal Years_. Footnote 28: From statistics furnished by Mr. R. Johnson, traffic supervisor, Illinois Bell Telephone Company. Footnote 29: From 1912–23, land values per front foot increased in Bridgeport from $600 to $1,250; in Division-Ashland-Milwaukee district, from $2,000 to $4,500; in “Back of the Yards,” from $1,000 to $3,000; in Englewood, from $2,500 to $8,000; in Wilson Avenue, from $1,000 to $6,000; but decreased in the Loop from $20,000 to $16,500. Footnote 30: Nels Anderson, _The Slum: An Area of Deterioration in the Growth of the City_; Ernest R. Mowrer, _Family Disorganization in Chicago_; Walter C. Reckless, _The Natural History of Vice Areas in Chicago_; E. H. Shideler, _The Retail Business Organization as an Index of Business Organization_; F. M. Thrasher, _One Thousand Boys’ Gangs in Chicago; a Study of Their Organization and Habitat_; H. W. Zorbaugh, _The Lower North Side; a Study in Community Organization_. Footnote 31: _Encyclopedia Americana_, New York (1923), p. 555. Footnote 32: