Section 6. The office of assessor provided for under the second section of the act entitled "An act to increase the revenue of the Commonwealth by taxation of the shares of the stock of the national banks," approved April twelfth, one thousand eight hundred and sixty-seven, is hereby abolished. That the limitation of the amount of state tax to be raised on personal property to the sum of five hundred thousand dollars, contained in the third section of the act of twenty-fourth of May, one thousand eight hundred and seventy-eight, entitled "An act defining the powers and extending the duties of the board of revenue commissioners," in words following: "Which tax shall not, as finally adjusted, exceed in the aggregate the sum of five hundred thousand dollars, be and the same is hereby repealed. The eleventh and seventeenth sections of the act to which this is a supplement are hereby repealed, saving, reserving, and excepting unto the commonwealth the right to collect any taxes accrued or accruing under said sections, prior to the date of the approval of this act.