Contribution to public purpose

After providing for the reserve fund and the education fund, a society may set aside a sum not exceeding twenty per cent. of its net profits, and utilise from time to time, with the approval of the Registrar, whole or part of such sum in contributing to any purpose as may be prescribed, or to any charitable purpose within the meaning of section 2 of the Charitable Endowments Act, 1890, or to any other public purpose.