XXI. And, for raising Money to enable the said Commissioners to carry the several Purposes of this Act into Execution, be it further enacted, That the said Commissioners shall, and are hereby authorized and empowered, Once in every Year, between _Lady Day_ and _Midsummer Day_, to rate and assess such Sums of Money as they shall from Time to Time judge necessary, upon the respective Occupiers of the several Houses, and other Buildings, Lands, and Grounds, within the Limits of this Act, not exceeding Two Shillings and Sixpence in the Pound of the annual Value of such respective Houses and other Buildings, with the Gardens and Yards hereunto belonging or held therewith, and not exceeding One Shilling in the Pound of the annual Value of the other Lands or Grounds within the said Limits; such respective annual Values to be ascertained by the respective Sums the same shall be rated to the Relief of the Poor, or in such other Manner as the said Commissioners shall think proper; and the Full Year for which such Rates or Assessments shall be made shall commence upon the Twenty-fourth Day of _June_ One thousand seven hundred and ninety; and the Money so rated and assessed shall from Time to Time be paid to the Collectors to be appointed as aforesaid, at such Time or Times in every Year, and in such Manner, as the said Commissioners shall order and direct, and shall be paid over by such Collectors into the Hands of the Treasurer to the said Commissioners. Empty Houses to be charged with Half Rates.