In all actions where executors and administrators are parties, such book account for all articles delivered within two years previous to the death of the deceased may be proved under the like circumstances, rules and conditions; and in such case, the executor or administrator may prove by himself that he found the account so stated on the books of the deceased; that there are no witnesses, to his knowledge, capable of proving the delivery of the articles which he shall propose to prove by said book, and that he believes the same to  be just, and doth not know of any other or further credit to be given  than what is therein mentioned: Provided, that if two years shall not have elapsed previous to the death of the deceased, the executor or administrator may prove the said book account, if the suit shall be commenced within three years from the delivery of the articles: Provided further, that whenever by the aforesaid proviso the time of proving a book account in manner aforesaid is enlarged as to the one party, to the same extent shall be enlarged the time as to the other party. (1756, c. 57, s. 2, P.R.; 1796, c. 465, P.R.; R.C., c. 15, s. 2; Code, s. 592; Rev., s. 1623; C.S., s. 1787.)