On or before the 15th day of May in each year the assessor must complete his assessment book and deliver the same to the Clerk of the Board, who must immediately give notice thereof and of the time the Board of Directors, acting as a Board of Equalization, will meet to equalize assessments, by publication of such notice in a newspaper published in the county for two successive weeks. The time fixed for the meeting shall not be less than ten (10) nor more than (20) days from the date of the first publication of the notice and in the meantime the Assessor's books shall remain in the office of the secretary for the inspection of all persons interested.