Opinion as to handwriting

(1) Where there is a question as to the person by whom any document was written or signed, the opinion of any person acquainted with the handwriting of the supposed writer that it was or was not written or signed by him is admissible in evidence. (2) A person is deemed to be acquainted with the handwriting of another person when he has at any time seen that person write, or when he has received documents purporting to be written by that person in answer to documents written by himself, or under his authority, and addressed to that person, or when, in the ordinary course of business, documents purporting to be written by that person have been habitually submitted to him.