18. (1) Every medical certificate under this Act shall be made and signed by a medical practitioner or a medical officer, as the case may be, and shall be in the form prescribed.(2) Every medical certificate shall state the facts upon which the person certifying has formed his opinion that the alleged lunatic is a lunatic, distinguishing facts observed by himself from facts communicated by other; and no reception order on petition shall be made upon a certificate founded only upon facts communicated by others.(3) Every medical certificate made under this Act shall be evidence of the facts therein appearing and of the judgment therein stated to have been framed by the person certifying on such facts, as if the matters therein appearing had been verified on oath.