No. 10715. Argued June 18, 1952. Filed August 15, 1952. Rehearing Denied October 8, 1952. Elizabeth W. Weston, Washington, D.C., (George J. Bott, Gen. Counsel, David P. Findling, Associate Gen. Counsel, A. Norman Somers, Assistant Gen. Counsel, Margaret M. Farmer, Washington, D.C., on the brief), for National Labor Relations Board. Louis H. Wilderman, Philadelphia, Pa. (Richard H. Markowitz, Philadelphia, Pa., on the brief), for respondent Union. Robert G. Kelly, Philadelphia, Pa., on the brief,