Banks Book of Evidence:
4. Affidavits shall be confined to such facts as the witness is able of his own knowledge to prove, and shall state his means of knowledge thereof, except on interlocutory motions, on which statements as to his belief, with the grounds thereof, may be admitted. The costs of any affidavit which shall unnecessarily set forth matters of hearsay or argumentative matter, or copies of or extracts from documents, shall not be allowed.
The Banks Book of Evidence 1879 & 1959 says the person signing must have knowledge of the evidence !!!!!! so most affidavits are nil and void.