The tax list of every person shall be made out on one of the printed lists; and the blanks in the list shall be filled in ink, and the oath appended shall be taken by the person rendering the list, and be subscribed before and certified by the assessor or other officer authorized to administer oaths. The lists shall be delivered to the assessor on or before the first day of April of the year in which the assessment is made; and he shall preserve them and deliver them, arranged alphabetically and securely bound together, to the board of supervisors. Thereafter these lists shall be preserved by the assessor for a period of three (3) years.