Said Assessor shall estimate, according to state law, the value of every parcel of real property and set the same down opposite such description. The roll shall show separate figures for the value of the land and of the building improvements. He shall also estimate the value of all taxable personal property of each person and set the same down opposite the name of such person. Except in the case of uniform general increases in property assessments in which cases notice shall be given by publication, the Assessor shall give notice by first class mail of any increase in the assessment of any property to the owner thereof of record according to the last assessment roll of the city addressed to the address of such owner shown on such roll, but the failure on the part of the Assessor to give any such notice or of any such owner to receive any such notice shall not invalidate any assessment roll of the city or any assessment thereon.