§ "For the further protection of the Howard de Walden Estate the following provisions shall unless otherwise agreed between the owner and the Postmaster-General have effect (that is to say):—
§ (1) In this Section the expression `the Howard de Walden Estate' means the premises in the Metropolitan Borough of Marylebone of which the Right Honourable Thomas Evelyn Baron Howard de Walden and Seaford is the freeholder or tenant for life and the expression the owner' means the said Right Honourable Thomas Evelyn Howard de Walden and 2806 Seaford or other the owner or owners for the time being of the said premises respectively
§ (2) The provisions of the Section of this Act of which the marginal note is "Power to take subsoil of public streets etc." shall not apply to any subsoil forming part of the Howard de Walden Estate and situate beneath any cellar vault subway or other similar structure under any public street road footway or place but subject to the provisions of this Act the Postmaster-General may purchase or take and the owner shall sell an easement or right of using any such subsoil which the Postmaster-General may require for the purposes of this Act and the provisions of the Lands Clauses Acts with respect to lands shall subject to the provisions of this Act extend and apply to any such easement or right of user except that no such easement or right of user shall be deemed part of a house or other building or manufactory within the meaning of Section ninety-two of the Lands Clauses Consolidation Act 1845 and that any question of disputed purchase money or compensation under this Sub-section shall be settled by arbitration in manner prescribed by the Lands Clauses Acts:
§ (3) In constructing any part of Railway No. 1 by this Act authorised in or under any property forming part of the Howard de Walden. Estate the Postmaster-General shall not acquire any easements nor construct any permanent works in any property forming part of the said estate and lying between Wells Street on the east and Marylebone Lane on the west at a higher level than that at which the tunnels of the said railway may be constructed under the powers of this Act:
§ (4) When estimating under the provisions of the Acts incorporated with this Act the purchase money or compensation payable under this Act to the owner in respect of any easement or right acquired by the Postmaster-General in any subsoil or undersurface forming part of the Howard de Walden Estate no regard shall be had to any injurious affection which may be caused to the Howard de Walden Estate or any part thereof by reason of the execution of the works authorised by or the exercise of the powers of this Act but if any such injurious affection shall be caused by reason of the execution of such works or the exercise of such powers the owner shall thereupon be entitled to compensation in respect thereof under the provisions 2807 of the Acts incorporated herewith to the same extent (if any) as the owner would but for this enactment have been entitled to compensation under the said provisions. Provided always that any claim so made for such injurious affection shall except as hereinafter provided be made within the period of two years from the commencement of the working of the railway and that any such claim and any claim made by the owner under the provisions of the Section of this Act of which the marginal note is "Compensation for damage by working" shall except as hereinafter provided be referred to and determined by the same arbitrator and that such arbitrator shall be appointed in default of agreement by the President of the Surveyors' Institute on the application of either party and the provisions of the Arbitration Act 1889 shall apply to any such arbitration:
§ Provided also that if any substantial change is made in the weight or size of the rolling stock used on or in the method of working the said part of Railway No. 1 any claim for injurious affection to the Howard de Walden Estate caused by the working of the railway after such change has been made may be brought within two years from the time when such change is made and shall be determined by an arbitrator to be appointed as aforesaid."