33 U.S.C. § 873 : US Code - Section 873: Extra compensation for instrument observers, recorders and other Federal employees for oceanographic, seismographic and magnetic observations

Search 33 U.S.C. § 873 : US Code - Section 873: Extra compensation for instrument observers, recorders and other Federal employees for oceanographic, seismographic and magnetic observations

The Secretary of Commerce is authorized to pay extra compensation
to members of crews of vessels when assigned duties as instrument
observer or recorder, and to employees of other Federal agencies
while observing tides or currents, or tending seismographs or
magnetographs, at such rates as may be specified from time to time
by him and without regard to section 5533 of title 5.