The books in which merchants, traders, and business men generally keep their accounts. Parris v. Bellows. 52 Vt. 351; Com. v. Williams, 9 Mete. (Mass.* 273; Wilson v. Wilson, 6 N. J. Law, 00; Security Co. v. Graybeal, 85 Iowa. 543, 52 N. W. 407. 39 Am. St. Rep. 311; Colbert v. Piercy, 25 N. C. 80.