Section
50, acts Aug. 24, 1912, ch. 355, 8, 37 Stat. 487; June 6, 1939, ch. 185, 53 Stat. 810, authorized collectors of customs to administer oaths to expense accounts. Section
51, act Mar. 4, 1923, ch. 251, 7, 42 Stat. 1454, provided limitations on compensation.