Voluntary disclosure of income (1) Where any person makes a declaration in accordance with sub section (2) in respect of the amount representing income (a) which he has failed to disclose in a return of income for any assessment year filed by him before the first day of March 1965 under the Indian Income tax Act 1922 (Xl of 1922) or the Income tax Act 1961 (XLIII of 1961) or (b) which has escaped assessment for any assessment year for which an assessment has been made before the 1st day of March 1965 under either of the said Acts or (c) for the assessment of which no proceeding under either of the said Acts has been taken before the 1st day of March 1965, he shall notwithstanding anything contained in the said Acts be charged income tax at the rate specified in sub section (3) in respect of the amount so declared if he (i) pays the amount of income tax as computed at the said rate or (ii) furnishes adequate security for the payment there of in accordance with sub section (4) and under takes to pay such income tax within a period not exceeding six months from the date of the declaration as may be specified by him therein or (iii)On or before the 31st day of May 1965 pays such amount as is not less than one half of the amount of income tax as computed at the said rate or furnishes adequate security for the payment there of in accordance with sub section (4) and in either case assigns any shares in or debentures of a joint stock company or mortgages any immovable property in favour of the President of India by way o f security for the payment of the balance and undertakes to Fay such balance within the period referred to in clause (ii).