In compliance with the provisions of section 3 of the civil-service
act the Commission shall provide examinations for the classified
departmental service at least twice in each year in every State or
Territory in which there are a sufficient number of applicants for such
examinations; and the places and times of examinations shall, when
practicable, be so fixed that each applicant may know at the time of
making his application when and where he may be examined; but applicants
may be notified to appear at any place at which the Commission may order
an examination.