1930. Adams, J. E. (James Edward), 1898-, Burke, R. T. Avon (Richard Thomas Avon), 1878-cartographer., Bushnell, T. M. (Thomas Mark),1889-1976, Simmons, C. S. (Charles Shaffer),1900-cartographer., and Ulrich, H. P. (Herbert Paul), 1904-cartographer. Shows soil types classification by colors and symbols. 'Field operations Bureau of Chemistry and Soils 1930. 'Williams & Heintz Co. Wash. D.C.' Sca... Bureau of Chemistry and Soils.