Place of removal interpretation: property retained during transit means valuation at buyer's premises determines central excise assessable value. Interpretation of place of removal governs which location's price forms assessable value: where goods insured in the seller's name remain the seller's property in transit, property passes at buyer's premises and that location may be the place of removal for valuation. Equalised transit insurance charges collected in excess of actual outlay are not automatically includable in assessable value. The statutory penalty equal to determined duty is a maximum; authorities may impose a lesser penalty after considering circumstances.