789. An English will, whether affecting movable or immovable property, must be in writing and signed at the end with the signature of the testator, or his or her mark, made by himself or herself or by another person for him or her, in his or her presence, and under his or her express direction, which signature or mark is then or subsequently acknowledged by the testator as having been subscribed by him or her to his or her will then produced, in presence of at least 2 competent witnesses, one of whom must be a Justice of the Peace, who attest and sign the will immediately in presence and at the request of the testator, and in the presence of one another. The signature of a witness cannot be by mark.