Use of force or threats to compel continuance in or departure from employment. Unlawful assemblages near site of labor dispute. Interference with lawful exercise of business activity. Interference with public ways of travel, transportation, or conveyance by mass picketing near site of labor dispute. Use of force or threats to compel or prevent labor organization membership or to compel or prevent strike participation. Penalty for unlawful picketing and for unlawful interference with employment or business activity. Payment of charges by carriers or shippers for movement of motor vehicles to or by rail facilities; receipt by labor organizations of such payments; penalties. Sec.