3. Charge of gift- tax. Subject to the other provisions contained in this Act, there shall be charged for every 1[ assessment year] commencing on and from the 1st day of April, 1958 , a tax (hereinafter referred to as Gift- tax) in respect of the gifts, if any, made by a person during the previous year (other than gifts made before the 1st day of April, 1957 ) at the rate or rates specified in the Schedule.