S. 147 : Reassessment-With in four years-Depreciation-Goodwill-Query raised and reply was filed-Issue was considered in the course of assessment proceedings-Audit-Even if it is an error that the Assessing Officer discovered, still the error discovered on a reconsideration of the same material does not give him power to reopen the assessment-Change of opinion-Reassessment notice and order disposing the objection is quashed. [S. 32, 148, Art. 226]