Section, acts June 25, 1948, ch. 646, 62 Stat. 950; May 24, 1949, ch. 139, § 95, 63 Stat. 103; Oct. 5, 1949, ch. 601, 63 Stat. 704; July 7, 1952, ch. 581, 66 Stat. 439; July 28, 1955, ch. 424, § 3, 69 Stat. 394, related to payment of witnesses fees to officers and employees of the United States. See sections 5515, 5537, 5751, and 6322 of Title 5, Government Organization and Employees.