(1)For the purposes of this Act, a certificate by any Minister as to what government war work has been done on any land, as to what government war use has been made of any land, as to what damage has occurred on any land owing to government war use thereof, as to the periods for which any land was in his possession or in. that of any other Minister or in the possession of any person occupying or using it under his authority or that of any ether Minister, and as to whether any specified works were constructed on, over or below the surface of any land wholly or partly at the expense of the Crown or by arrangement with any Minister, shall be evidence of the facts therein stated.
(2)Every document purporting to be a certificate authorised or required by this Act and to be signed by or on behalf of a Minister or other person shall be received in evidence and shall, until the contrary is proved, be deemed to be such a certificate of that Minister or person, and in any legal proceedings (including arbitrations) -the production of a document purporting to be certified by or on behalf of the Minister or person having power to give any such certificate as aforesaid to be a true copy of such a certificate shall, unless the contrary is proved, be sufficient evidence of the certificate.