No. 16250. Argued May 2, 1962. Decided July 19, 1962. Mr. Sherman Carmell, Chicago, Ill., of the bar of the Supreme Court of Illinois, pro hac vice, by special leave of court, with whom Mr. Herbert S. Thatcher, Washington, D.C. was on the brief, for petitioners. Messrs. James F. Carroll and Donald M. Murtha, Washington, D.C., entered an appearance for petitioners. Mr. Melvin J. Welles, Atty., N.L.R.B., of the bar of the Court of Appeals of New York, pro hac vice, by special leave of court, with whom