(5) which in so far as it is relevant for our purpose is in these terms "Any deduction made and paid to the account of the Central Government in accordance with the provisions of this section and any sum which a dividend has been increased under sub section (2) of section 16 shall be treated as a payment of income. tax or super tax on behalf 675 of the person from whose income the deduction was made, or of the owner of the security or of the shareholder, as the case may be, and credit shall be given to him therefor on the production of the certificate, furnished under subsection (9) or section 30, as the case may be in the assessment, if any, made for the following year under,this Act Provided that, if such person or such owner obtains, in accordance with the provisions of this Act, a refund of any portion of the tax so deducted, no credit shall be given for the amount of such refund: xx xx xx xx xx xx xx xx Put briefly, the scheme of section 18 is to provide for deduction of income tax at the source in respect of certain categories of income.