(a)Letters will be classified as follows according to the period for which they are to be preserved:-"A" to be preserved permanently or for an indefinite period."B" ditto for ten years."C" ditto for two years.In the list given in Appendix LXIII the various files or subjects have been classified accordingly.(b)On receipt of a letter in office and before it is submitted to the Superintendent the head clerk will mark clearly on the letter in red pencil or red ink the letter "A", "B" or "C" according to the period for which it is to be preserved.It is to be understood that although a subject as classed in the Appendix referred to above is to be preserved permanently or for 10 years, it is not intended that all letters, even of trivial importance dealing with the subject, must be preserved for that period. The head clerk shall use his discretion and even a letter dealing with subject classed "A" or "B" should be marked "C" if it be only of temporary importance. If in doubt the head clerk shall take the orders of the Superintendent.
