39. (1) Where, for any assessment year, the result of computation of income in respect of any speculation business carried on by the assessee is a loss, it shall be set off only against the income, if any, from any other speculation business carried on by him and assessable for that assessment year. (2) Where, for any assessment year, any loss computed in respect of a speculation business has not been wholly set off under sub-section (1), so much of the loss as has not been so set off, or the whole loss where the assessee has no income from any other speculation business, shall, subject to the provisions of this Ordinance, be carried forward to the next following assessment year, and- (a) it shall be set off against the income, if any, from any speculation business carried on by him and assessable for that assessment year; and (b) if the loss cannot be wholly so set off, the amount of loss not so set off shall be carried forward to the next assessment year and so on for not more than six successive assessment years.