Thames Borough v Thames Valley Electric Power Board - [1957] NZLR 523

Contract — Construction — Electric Power Board's Agreement with Borough for Supply of Electricity — Alteration of Charges and Graduated Scale by Department supplying Electricity to Board — Calculation of Increased Charges to Borough in Accordance with Agreement — Charges to be "correspondingly increased or diminished" — New Charges to be paid by Borough to stand in Same Relationship to New Price paid as Original Price fixed under Agreement bore to Price or Rate then being paid by the Electric Power Board.