A simple contract regarding the same matter and based on no new consideration does not destroy another simple contract between the same parties; but, if new parties are introduced so as to change the person to whom the obligation is due, the original contract is at an end. (Orig. Code 1863, § 2686; Code 1868, § 2682; Code 1873, § 2724; Code 1882, § 2724; Civil Code 1895, § 3641; Civil Code 1910, § 4226; Code 1933, § 20-115.)