Act Mar. 6, 1952, ch. 94,
66 Stat. 16, as amended by acts Aug. 31, 1954, ch. 1168,
68 Stat. 1044;
Pub. L. 85–156, Aug. 21, 1957,
71 Stat. 390;
Pub. L. 85–611, § 3, Aug. 8, 1958,
72 Stat. 543;
Pub. L. 86–308, § 2, Sept. 21, 1959,
73 Stat. 585, provided that the authority vested in the Secretary of the Interior by sections
485b and
485f of this title should be extended through Dec. 31, 1960.