[27] Ibid., pp. 26-29 passim.
[28] Op. cit., p. 32.
[29] Philadelphia is the only city which has had adequate study. Vide DuBois, W.E.B., The Philadelphia Negro, (Philadelphia, 1889) and Wright, R.R., Jr., The Negro in Pennsylvania, a Study in Economic History (Philadelphia, 1912).
[30] Vide Weber, op. cit., passim.
[31] Ibid., 232 ff.; 241 ff.; 283 ff.; 346-364, passim.
[32] A suggestive study on this phase of the city problem has been published recently: Industrial Causes of Congestion of Population in New York City, by E.E. Pratt, Ph.D., (New York, 1911), pp. 5-262.
[33] Weber, op. cit., pp. 161-169; 223.
[34] Ibid., pp. 171-173; 181-182; 223-224.
[35] Weber, op. cit., pp. 184-191.
[36] Ibid., pp. 210, 213-222.