Consequently there was no merger of such estates by the purchase of the title in the one instance and of the lien on the same land in the other, and no discharge of the lien so purchased. North Texas Building Loan Ass'n v. Overton, 126 Tex. 104, 86 S.W.2d 738; King v. Hampton, 131 Tex. 85, 113 S.W.2d 173, 174; Cooper v. First State Bank, Tex. Civ. App. 121 S.W.2d 399; 17 Tex.Jur., § 27, p. 122. Under the rules announced in the decisions above cited, the bank was not required to sue all of the makers, all being jointly and separately liable for the whole of the indebtedness; but could sue any one or more of them.