(1) This section shall apply to any person carrying on farming, the profits or gains of which are chargeable to tax in accordance with section 655.
(a) Where a person to whom this section applies incurs, for the purpose of a trade of farming land occupied by such person, any capital expenditure on the construction of farm buildings (excluding a building or part of a building used as a dwelling), fences, roadways, holding yards, drains or land reclamation or other works, there shall be made to such person during a writing-down period of 7 years beginning with the chargeable period related to that expenditure, writing-down allowances (in this section referred to as "farm buildings allowances") in respect of that expenditure and such allowances shall be made in taxing the trade.
(b) As respects each of the first 6 years of the writing-down period, the farm buildings allowance to be made under this subsection shall be 15 per cent of the capital expenditure referred to in paragraph (a)
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