The motion for leave to file petition for rehearing is granted. The petition for rehearing is granted. The order denying certiorari, 311 U. S. 673, is vacated and the petition for writ of certiorari to the Circuit Court of Appeals for the Seventh Circuit is granted, limited to the question whether claims 2, 3, and 11 of the Mead patent No. I, 736,544 are valid.