It provides "Where, in any of the assessments for the years beginning on the 1st day of April of the years 1948 to 1955 inclusive, a rebate of income tax was allowed to a company on a part of its total income under clause (i) of the proviso to Paragraph B of Part I of the relevant Schedules to the Finance Acts specifying the rates of tax for the relevant year, and subsequently the amount on which the rebate of income tax was allowed as aforesaid is availed of by the company, wholly or partly, for declaring dividends in any year, the amount or that part of the amount availed of as aforesaid, as the case may be, shall, by reason of the rebate of incometax allowed to the company and to the extent to which it has not actually been subjected to an additional income tax in accordance with the provisions of clause (ii) of the proviso to Paragraph B of Part I of the Schedules to the Finance Acts above referred to,.