The relevant provisions, as in force at the relevant time, were: section 10(2) Such profits or gains shall be computed after making the following allowances, namely (iv)in respect of insurance against risk of damage or destruction of buildings, machinery, plant, furniture, stocks or stores, used for the purposes of the business, profession or vocation, the amount of any premium paid; (v) in respect of current repairs to such buildings, machinery, plant or furniture, the amount paid on account thereof; (vi)in respect of depreciation of such buildings, machinery, plant, or furniture being the property of the assessee, a sum equivalent, where the assets are ships other than ships ordinarily plying on inland waters, to such percentage on the original cost thereof to the assessee as may in any case or class of cases be prescribed and in any other case, to such percentage on the written down value thereof as may in any case or class of cases be prescribed; and where the buildings have been newly erected, or the machinery or plant being new has been installed, after the 31st day of March, 1945, a further sum (which shall however not be deductible in determining the written down value for the purposes of this clause) in respect of the year of erection or installation equivalent, (a) in the case of buildings the erection of which is begun and completed between the 1st day 849 of April 1946 and the 31st day of March 1952 (both dates inclusive), to fifteen per cent of the cost thereof to the assessee; (b) in the case of other buildings, to ten per cent of the cost thereof to the assessee; (c) in the case of machinery or plant, to twenty per cent of the cost thereof to the assessee: Provided that (via) in respect of depreciation of buildings newly erected, or of machinery or plant being new which has been installed, after the 31st day of March, 1948, a further sum (which shall be deductible in determining the written down value) equal to the amount admissible under clause (vi) (exclusive of the extra allowance for double or multiple shift working of the machinery or plant and the initial depreciation allowance admissible under that clause for the first year of erection of the building or the installation of the machinery or plant) in the assessments for such of the five years commencing on the 1st day of April, 1949, and ending with the 31st day of March, 1954: Provided that where, in respect of such machinery or plant, the assessee establishes that the market value of similar machinery or plant on the 31st day of March, 1953, is lower than the original cost, then, subject to the provisions of clause (vi), there shall be made in the assessment for the year commencing next after that date a further allowance (which shall be deductible in determining the written down value) of an amount by which the written down value of the machinery or plant as on that date (without deduction of the initial depreciation admissible in the first year) would have exceeded the corresponding written down value thereof as on the same date if the market price of the machinery or plant had been taken as the actual cost of the assessee; (vii)in respect of any such building, machinery or plant which has been sold or discarded or demolished or destroyed, the amount by which the written down value thereof exceeds the amount 850 for which the building, machinery or plant, as the case may be, is actually sold or its scrap value: Provided that (5) In sub section (2) . . `plant ' includes vehicles, books, scientific apparatus and surgical equipment purchased for the purpose of the business, profession or vocation. ." The point at issue before us has been considered by three High Courts.