(1) Subject to the provisions of this section, where any person makes, on or after the 19th day of August, 1965, and before the 1st day of April, 1966, a declaration in accordance with sub section (2) in respect of the amount representing income chargeable to tax under the Indian Income tax Act, 1922 (11 of 1922), or the Income tax Act, 1961 (43 of 1961), for assessment year commencing on or before the 1st day of April, 1964 (a) for which he has failed to furnish a return within the time allowed under section 22 of the Indian Income tax Act, 1922 (11 of 1922), or section 139 of the Income tax Act, 1961 (43 of 1961), or G (b) which he has failed to disclose in a return of in come filed by him on or before the 19th day of August, 1965, under the Indian Income Tax Act, 1922 (11 of 1922) or the Income Tax Act, 1961 (43 of 1961), or 858 (c) which has escaped assessment by reason of the omission or failure on the part of such person to make a return under either of the said Acts to the Income tax officer or to disclose fully and truly 11 material facts necessary for his assessment.