Said commission shall organize by the selection of such officers as may be required in the performance of its duties the same to be selected from the members thereof. The members of said commission shall receive no greater compensation than is now allowed by law to each, respectively, as an officer of said Corps of Engineers. It shall also adopt rules and regulations, not inconsistent with law, to govern its deliberations and prescribe the method of procedure under the provisions of this chapter. While traveling on duty the officers of the commission shall receive the mileage allowed by law.
33 U.S. Code § 662. Organization; compensation of members; rules and regulations of procedure; traveling expenses
The last sentence of this section is from a provision accompanying an appropriation for the expenses of the Commission in the Sundry Civil Appropriation Act for 1901, which originally read as follows:
Act Mar. 3, 1899, ch. 424, § 1, 30 Stat. 1109, mentioned in said provision, provided that the officers of the Commission traveling on duty might be paid their actual traveling expenses, in lieu of mileage allowed by law, and should thereafter receive no mileage.