Smith v Birkenhead Corporation By the Birkenhead Improvement Act 1884, Sched II, it is provided that, when certain works for the improvement of private streets are undertaken by the corporation, the estimated expenses of executing the works shall be provisionally apportioned among the premises fronting or adjoining or abutting on such street, and that the provisional apportionment “shall also state whether the apportionment is made according to the frontage of the respective premises, or not, and the measurements of the frontages and the other considerations (if any) on which the apportionment is based.