Candidates for appointment to positions the salary of which is less than $1,200 will be examined in like manner upon the following subjects: (1) Penmanship, (2) copying; (3) elements of English grammar, chiefly orthography and syntax; and (4) fundamental rules of arithmetic. Proficiency in penmanship, orthography, and punctuation will be determined principally by a review of the examination papers, and as far as possible the examination in all the branches will be confined to practical exercises. In examinations for appointments to positions requiring special or technical knowledge such additions may be made by the board of examiners to the list of subjects as the nature of the case may require. For temporary employment to meet casual exigencies in the public business, or for special services as experts, appointments may be made without examination; but no such appointment shall be made for a term exceeding three months, which may be specially extended for a similar term only; and no such appointment shall be made to any regular or permanent position. IX. The various subjects of the examination may be subdivided, if thought desirable, into classes, and to each subject or class a relative weight, according to its importance in the examination, will be assigned by each board of examiners. The mode of ascertaining the result of the examination will be as follows: The degree of accuracy with which each question shall be answered will first be marked by the board on a scale of 100. The average of the marks given to the answers to the questions in each subject or class will next be ascertained. Each average will then be multiplied by the number indicating the relative weight of the subject or class, and the sum of the products will be divided by the sum of the relative weights. The quotient will determine the candidate's standing in the examination. Relative weight will be assigned not merely to the special qualifications of the candidates, but to their general aptitude, as shown in the course of examination. Candidates will be examined during office hours, and in no case will their examination be continued more than one day. X. The board of examiners will prepare a list of the persons examined in the order of their excellence, as proved by such examination, beginning with the highest, and will then certify to the head of the office the names standing at the head of such list, not exceeding three. When more than one appointment is to be made, the vacancies will be numbered, and the first three names will be certified for the first vacancy, the remaining two and the fourth for the second vacancy, the remaining two and the fifth for the third vacancy, and so on for the whole number of vacancies; but if, after selecting one of any three certified for appointment, the head of the office shall object to another presentation of either of the remaining names, it shall not be again certified.