§ 318.
The Secretary of Commerce, in cooperation with the United States Postal Service, may arrange a plan by which there shall be displayed on all cars and other conveyances used for transporting United States mail suitable flags or other signals to indicate weather forecasts, cold-wave warnings, frost warnings, and so forth, to be furnished by the Secretary.
([Apr. 25, 1896, ch. 140], [29 Stat. 108]; 1940 Reorg. Plan No. IV, § 8, eff. June 30, 1940, 5 F.R. 2421, [54 Stat. 1236]; 1965 Reorg. Plan No. 2, §§ 1, 2, eff. July 13, 1965, 30 F.R. 8819, [79 Stat. 1318]; [Pub. L. 91–375, § 4(a)], Aug. 12, 1970, [84 Stat. 773].)