39.—(1)  Compensation under this Act shall not be payable for a 1923 Act improvement specified in Part I of the Second Schedule to this Act or for a 1931 Act improvement specified in Part I of the Third Schedule thereto unless, before the carrying out thereof, the landlord consented in writing (whether unconditionally or upon terms as to compensation or otherwise agreed on between him and the tenant) to the carrying out thereof.

    (2)  Where the consent was given upon terms as to compensation agreed on as aforesaid, the compensation payable under the agreement shall be substituted for compensation under this Act.

        40.—(1)  Compensation under this Act shall not be payable for a 1923 Act improvement specified in Part II of the Second Schedule to this Act unless the tenant, not more than three nor less than two months before he began to carry out the improvement, gave to the landlord notice in writing under section three of the Agricultural Holdings (Scotland) Act, 1923, of his intention to carry out the improvement and of the manner in which lie proposed to carry it out, and either—

Provided that this subsection shall not have effect if the landlord and the tenant agreed, by the lease or otherwise, to dispense with notice under the said section three.

    (2)  Compensation under this Act shall not be payable for a 1931 Act improvement specified in Part II of the Third Schedule to this Act unless the tenant, not more than six months nor less than three months before he began to carry out the improvement, gave to the landlord notice in writing under section three of the Agricultural Holdings (Scotland) Act. 1923. of his intention to carry out the improvement and of the manner in which he proposed to carry it out and either—

Provided that this subsection shall not have effect—

    (3)  If the landlord and the tenant agreed (whether after notice was given under the said section three or by an agreement to dispense with notice under that section) on the terms as to compensation on which the improvement was to be carried out, the compensation payable under the agreement shall be substituted for compensation under this Act.

    (4)  In this section the expression "the appropriate authority" means, in relation to the period before the fourth day of September, nineteen hundred and thirty-nine, the Department of Agriculture for Scotland , and in relation to the period commencing on that day, the Secretary of State.

        41.     Compensation under this Act shall not be payable in respect of any such repairs as are specified in paragraph 29 of the Second Schedule to this Act or in paragraph 29 of the Third Schedule thereto unless, before beginning to execute any such repairs, the tenant gave to the landlord notice in writing under paragraph (29) of the First Schedule to the Agricultural Holdings (Scotland) Act, 1923, or under paragraph (30) of the First Schedule to the Small Landholders and Agricultural Holdings (Scotland) Act, 1931, of his intention to execute the repairs, together with particulars thereof and the landlord failed to exercise the right conferred on him by the said paragraph (29) or the said paragraph (30) to execute the repairs himself within a reasonable time after receiving the notice.

        42.     Where an agreement in writing entered into before the first day of January, nineteen hundred and twenty-one, secures to the tenant for an old improvement specified in Part III of the Second Schedule to this Act or in Part III of the Third Schedule thereto fair and reasonable compensation, having regard to the circumstances existing at the time of the making of the agreement, the compensation so secured shall as respects that improvement be substituted for compensation under this Act.

        43.     The tenant shall be entitled to compensation under this Act in respect of the 1931 Act improvement specified in paragraph 28 of the Third Schedule to this Act, being the laying down of temporary pasture in accordance with that paragraph, notwithstanding that the laying down or the leaving at the termination of the tenancy of such pasture was in contravention of the terms of the lease or of any agreement made by the tenant respecting the method of cropping the arable lands; but in ascertaining the amount of the compensation the arbiter shall take into account any injury to, or deterioration of, the holding due to the contravention except in so far as the landlord has recovered damages in respect of such injury or deterioration.

        44.—(1)  In the ascertainment of the amount of the compensation payable under this Act to the tenant in respect of an old improvement, there shall be taken into account—

    (2)  In assessing the amount of any compensation payable to the tenant, whether under this Act or under custom or agreement, by reason of the improvement of the holding by the addition thereto of lime in respect of which a contribution has been made under Part I of the Agriculture Act, 1937, the contribution shall be taken into account as if it had been a benefit allowed to the tenant in consideration of his carrying out the improvement, and the compensation shall be reduced accordingly.

    (3)  In assessing the amount of any compensation payable under this Act to the tenant in respect of such an improvement as is mentioned in paragraph (ii) of the proviso to subsection (2) of section forty of this Act, if it is shown to the satisfaction of the person assessing the compensation that the improvement consisted of, or was wholly or in part the result of or incidental to, operations in respect of which any grant has been or is to be made to the tenant out of moneys provided by Parliament, the grant shall be taken into account as if it had been a benefit allowed to the tenant in consideration of his carrying out the improvement, and the compensation shall be reduced to such extent as that person considers appropriate.

    (4)  Notwithstanding anything in the foregoing provisions of this Act, the tenant shall not be entitled to compensation thereunder for an old improvement carried out on land which, at the time the improvement was begun, was not a holding within the meaning of the Agricultural Holdings (Scotland) Act, 1923, as originally enacted, and would not have fallen to be treated as such a holding by virtue of section thirty-three of that Act.

    (5)  In this section the expression "manuring" means any of the improvements specified in paragraphs 25 to 27 of the Second Schedule to this Act or in paragraphs 25 to 27 of the Third Schedule thereto.