Lord Macmillan:-

The main question to be determined in this appeal relates to the basis on which the appellants are entitled to be compensated on the transfer to the respondents of an electric railway constructed by the appellants on the Canadian Bank of the Niagara River. There are also subsidiary questions (1) as to whether certain items of property should be included in computing the compensation, (2) as to the allowance of interest, and (3) as to costs. The respondents, the Niagara Parks Commission, formerly known as the Commissioners for the Queen Victoria Niagara Falls Park, are a statutory body which controls for the Government of Ontario a large area of land on the bank of the Niagara River above and below the Falls which has been developed as a public park under Statutes of 1885 (48 Vict. C. 21) and 1887 (50 Vict.C.13). The appellants are the successors of the Niagara Falls Park and River Railway Company which was incorporated in 1892 by a statute of the Ontario Legislature (55 Vict. C.96). By that statute an agreement dated 4th December 1891, entered into between the promoters of the railway in question and the Parks Commissioners was ratified and confirmed.

The agreement n