The right to alter, amend, or repeal this chapter is expressly reserved; but no such alteration, amendment, or repeal shall affect any license theretofore issued under the provisions of this chapter or the rights of any licensee thereunder.
June 10, 1920, ch. 285 41 Stat. 1077 Aug. 26, 1935, ch. 687 49 Stat. 847 (, pt. I, § 28, ; renumbered pt. I, , title II, § 212, .)