Rules of practice and procedure in administration of sec. 332, 336, 337, and 338, title 3, pt. 2, tariff act of 1930, and Laws relating to Tariff Commission, act creating Tariff Commission, sec. 330-341 and 350, title 3, pt. 2, sec. 402, title 4, pt. 1, and paragraph 51, title 1, tariff act of 1930.