12 U.S.C. § 178
Section, acts July 12, 1882, ch. 290, §9, 22 Stat. 164; Mar. 14, 1900, ch. 41, §12, 31 Stat. 49; Mar. 4, 1907ch. 2913, §4Mar. 4, 1907, 34 Stat. 1290, authorized national banking associations desiring to withdraw circulating notes to deposit money with Treasurer of United States and withdraw bonds or other securities securing such notes.