No defeasance to any deed for real estate, regular and absolute upon its face, made after the passage of this act, shall have the effect of reducing it to a mortgage, unless the said defeasance is in writing, signed and delivered by the grantee in the deed to the grantor; and, in so far as it may effect any subsequent grantee or mortgagee of such real estate, for value, unless it is also acknowledged and recorded in the office for the recording of deeds and mortgages in the county wherein the said real estate is situated, before the execution and delivery of such subsequent grant or mortgage; and such defeasances shall be recorded and indexed as mortgages by the recorder.
21 P.S. § 951