Notices, etc., purporting to be duly signed to be admitted in evidence

In any proceedings under this Act, or under any regulation or by-law made pursuant thereto, any notice, order, certificate or other instrument purporting to be signed by the Mayor of any Town Council or health officer, or any other person authorised and acting under this Act shall on production be admitted in evidence and shall be presumed to have been duly signed by the person and in the character by whom and in which it purports to be signed until the contrary is shown.