out in the form of deposits in another Bank to add to the profit instead of lying idle necessarily ceased to be a part of the stock­in­trade of the Bank, or that the interest arising therefrom did not form part of its business profits. Under the bye­laws one of the objects of the appellant Bank is to carry on the general business of Banking and therefore subject to the Cooperative Societies Act, it has to carry on its business in the manner that ordinary Banks do. It may be added that the various heads under Section 6 of the Income Tax Act and the provisions of that Act applicable to these various heads are mutually exclusive. Section 12 is a residuary section and does not come into operation until the preceding heads are excluded. CIT v. Basant Rai Takht Singh [(1933) ITR 197, 201].” (emphasis added) 16. The decision of the Privy Council in the case of Punjab Co­operative Bank v. Commissioner of Income Tax9 is also very relevant. It was held thus: “The principle to be applied in such