Depreciation scope broadened to include specified intangible assets and defined asset blocks for business deductions. Amendment expands allowable depreciation deductions to include tangible assets and specified intangible assets used in business, defines 'assets' and 'block of assets' to separate tangible and intangible categories, defines 'know-how,' and provides that where proceeds plus scrap value fall short of written down value on sale/disposal (other than in year of first use) the deficiency, if written off in the books, is allowable; 'moneys payable' and 'sold' (including exchange and compulsory acquisition) are specified, with an exclusion for certain amalgamation transfers.