“…Other materials which have been examined for attitudes include speeches (Eckhardt & l{hite, 1967;Prothro, 1956;vfuite, 1949), articles (Angell, Dunham, & Singer, 1964;Bernstein, 1953;Lane, 1951;Wilcox, 1962), letters (Baldwin, 1942;Cochran, 1953), and diaries (Osgood, 1959). Stuart (1963) has even employed grievance records to study racial attitudes.…”