The certificate of a notary public, justice of the peace, or other authorized officer, attached to a deed, mortgage, or other instrument, setting forth that the parties thereto personally appeared before him on such a date and acknowledged the instrument to be their free and voluntary act and deed. Read v. Loan Co., OS Ohio, St. 2S0, 07 N. E. 729, 62 L. R. A. 790, 96 Am. St Rep. 663.