Executive Order—Amendment of Civil Service Rules
Special Departmental Rule No. 1, section 6, is hereby amended by striking out the whole of said section and substituting therefor the following:
6. In the Department of Agriculture, in the office of the Secretary: Private secretary to the chief clerk, and wood engravers; scientific or professional experts employed for a period of not exceeding six months outside of Washington, D.C., in investigations specially authorized by Congress, but no such expert shall be reappointed as an expert unless the United States Civil Service Commission shall certify that such person has passed a suitable examination and is eligible for such appointment. This exception does not include any person to be employed in that Department in Washington, D.C., nor any person whose duties are not scientific or professional or who is not expert in the particular line of scientific or professional inquiry in which such person is to be employed.
Grover Cleveland, Executive Order—Amendment of Civil Service Rules Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/206529