Nos. 73-1019, 73-1480. Argued October 3, 1973. Decided December 14, 1973. Winthrop A. Johns, Washington, D.C. and Joseph A. Yocum, Evansville, Ind. (Johns Zimmerman, Washington, D.C. and Kahn, Dees, Donovan Kahn, Evansville, Ind., on brief), for petitioner in No. 73-1019. Gerard C. Smetana, Chicago, Ill. (Milton A. Smith, Gen. Counsel, Otto F. Wenzler and Richard B. Berman, Labor Relations Counsel, Washington, D.C., S. Richard Pincus, Lederer, Fox Grove, Chicago, Ill., on brief), for amicus curiae