“The hemp tree in the Philippines reaches an average height of 10 feet. It is a native plant, the stem of which is inclosed in layers of half-round petioles. The hemp fiber is extracted from these petioles, which, when cut down, are separated into strips 5 to 6 inches wide, and drawn under a knife attached at one end by a hinge to a block of wood, while the other end is suspended from the extremity of a flexible stick. The bow tends to raise the knife and a cord attached to the same end of the knife, and a treadle is so arranged that, by a movement of the foot, the operator can bring the knife to work on the hemp petiole with the pressure he chooses.” CHAPTER XV. RULES FOR LETTER CARRIERS. How Mail Must Be Delivered--Work of Substitutes--Requirements, Uniforms, Etc. Letter carriers and substitute letter carriers are appointed by the Postmaster General on the nomination of the postmaster. Selection of persons for appointment as substitute letter carriers must be made by the postmaster from the carriers’ eligible register in the manner prescribed by the Civil Service Rules and the nominations submitted to the First Assistant Postmaster General (Division of Free Delivery), on Form 1101, together with the certificate for original appointment, Postal Service, Form 145, issued by the local Civil Service Board. When two or more persons are nominated on the same day for appointment as substitute letter carrier, their seniority shall be determined by their standing, or rating, on the eligible register, and not by the order of their selection. A vacancy in the regular force must be filled by the promotion of the senior substitute, whom the postmaster shall nominate for appointment on Form 1101. When a vacancy occurs in the regular force and there are no substitute letter carriers the nomination for appointment to fill such vacancy shall be made in the manner prescribed in the appointment of substitute letter carriers. The selection of letter carriers and substitute letter carriers at new free delivery offices, upon their establishment, is made from the carriers’ eligible register by the Postmaster General. When a vacancy occurs or an emergency arises necessitating the immediate appointment of a letter carrier and there are no available substitutes, and the eligible register contains less than three names, the postmaster may nominate, for temporary appointment not to exceed ninety days, any person of good character who is within the age limitations. A postmaster is not required to, but may make a selection from an eligible register containing less than three names.