1. Until promotion regulations have been applied to a classified customs
district, the following promotions may be made therein at any time after
absolute appointment:
(_a_) A clerk, upon any test of fitness determined upon by the
nominating officer, to any vacant place in the class next above the one
in which he may be serving.
(_b_) A day inspector, upon any test of fitness determined upon by
the nominating officer, to class 2 in the grade of clerk.
(_c_) A clerk, day inspector, opener and packer, or sampler, after
passing the examiner examination, to the grade of examiner.
(_d_) A messenger, after passing the clerk examination, to the
lowest class in the grade of clerk.
(_e_) A night inspector, after passing the day-inspector
examination, to the grade of day inspector.
2. Other promotions may be made, in the discretion of the promoting
officer, upon any test of fitness determined upon by him.