Discovery and inspection powers enable tax authorities to compel attendance, production and impoundment in tax inquiries. Clause 246 grants specified income tax authorities court like powers to order discovery and inspection, enforce attendance and oath examinations, compel production of books and documents, and issue commissions. Those powers may also be exercised by designated officers for inquiries or investigations even absent pending proceedings. Authorities may impound produced books or documents; the Assessing Officer or Assistant Director must record reasons for impounding and may retain them for up to fifteen days exclusive of holidays or longer with prior approving authority sanction.