1. The extension to the maker of a promissory note of the time of payment thereof will have the effect of discharging the surety only when the extension is for a definite period, for a valuable consideration, and without the consent of the surety. Luden v. Enterprise Lumber Co., 146 Ga. 284 (2), 287 (2) (91 S. E. 102, L. R. A. 1917 C, 485), and citations; Tanner v. Gude, 100 Ga. 157 (27 S. E. 938); Tatum v. Morgan, 108 Ga. 336 (33 S. E. 940).

2. “The notice to the creditor by a surety to proceed against the principal debtor, required by the statute, is written notice; an oral request will not suffice.” Timmons v. Butler, 138 Ga. 69 (1) (74 S. E. 784). *148The foregoing rulings dispose of the assignments of error in the exceptions pendente lite, and the grounds of the motion for a new trial were not argued.

Judgment affirmed.