Section 42 of the Act is in these terms: "(1) All income, profits or gains accruing or arising, whether directly or indirectly, through or from any business connection in the taxable territories ' (1) [1945]13I.T.R.465. 447 or through or from any money lent at interest and brought into the taxable territories in cash or in kind or through or from the sale, exchange or transfer of a capital asset in the taxable territories, shall be chargeable to income tax either in his name or in the name of his agent, and in the latter case such agent shall be deemed to be, for all the purposes of this Act, the assessee in respect of such income tax : Provided that where the person entitled to the income, profits or gains is not resident in the taxable territories, the income tax so chargeable may be recovered by deduction under any of the provisions of section 18 and that any arrears of tax may be recovered also in accordance with the provisions of this Act from any assets of the non resident person which are, or may at any time come within the taxable territories Provided further that any such agent, or any person who apprehends that he may be assessed as such an agent, may retain out of any money payable by him to such non resident person a sum equal to his estimated liability under this sub section, and in the event of any disagreement between the non resident person and, such agent or person as to the amount to be so retained, such agent or person may secure from the Income tax Officer a certificate stating the amount to be so retained pending final settlement of the liability, and the certificate so obtained shall be his warrant for retaining that amount Provided further that the amount recoverable from such agent or person at the time of final settlement shall not exceed the amount specified in such certificate except to the extent to which such agent or person may at such time have in his hands additional assets of such non resident person.