Opportunities as technical aids in science and engineering grades 2 and 3 in such fields as biology, geodesy, medicine, drafting, surveying, engineering, mathematics, cartography, meteorology, physical science, apply to Interagency Board of U.S. Civil Service Examiners for Washington, D.C., 1900 E Street, N.W. Washington, D.C. 20415, announcement WAP-920.