No. 76-1166. Argued June 6, 1977. Argued initially on October 7, 1976, before a panel consisting of WINTER, CRAVEN and HALL, Circuit Judges. Decided August 31, 1977. Richard A. Cohen, Atty., N.L.R.B., Washington, D.C. (John S. Irving, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Carl L. Taylor, Associate Gen. Counsel, Elliott Moore, Deputy Associate Gen. Counsel, Aileen A. Armstrong, Atty., N.L.R.B., Washington, D.C., on brief), for petitioner. N. Peter Lareau, Baltimore, Md. (A. Samuel