No. 12896. Argued March 19, 1956. Decided June 21, 1956. Mr. Joseph E. Finley, Washington, D.C., for petitioner. Miss Fannie M. Boyls, Attorney, National Labor Relations Board, with whom Mr. Marcel Mallet-Prevost, Assistant General Counsel, National Labor Relations Board, was on the brief, for respondent. Messrs. Clifford D. O'Brien and Richard Frank, Washington, D.C., filed a brief as amici curiae, urging affirmance. Before PRETTYMAN, BAZELON and DANAHER, Circuit Judges. PRETTYMAN, Circuit Judge