*313 Shepherd, J.:

“It is well settled that if a creditor enter intoan}' valid contract with the principal debtor, without the assent of the surety, by which the rights or liabilities of the surety are injuriously affected, such contract discharges the surety. A familiar instance of this is, where a creditor binds himself not to sue or collect the debt for a given time, and thereby puts it out of the power of the surety to pay the debt and sue the principal debtor.” Deal v. Cochran, 66 N. C., 269; Forbes v. Sheppard, 98 N. C., 111; Hollingsworth v. Tomlinson, 108 N. C., 245.

His Honor held that there was no valid contract of forbearance so as to bring the present case within vhe principles above stated, and the ruling is based upon the idea that the promise on the part of the principal debtor to pay the interest semi-annually did not amount to a sufficient consideration to support the agreement. A valuable consideration is “ any benefit to the person making the-promise, or any loss, trouble or any inconvenience to, or charge upon, the person to -whom it is made, * * * and provided there be some benefit, etc., * * * the Courts are not willing (in the absence of fraud) to enter into the question whether the consideration be adequate in value to the thing which is promised in exchange for it.” Smith on Contracts, 166, 168.

Tested by this rule, we are of the opinion that the alleged promise conferred a benefit upon the plaintiff, in that it worked a material change in the contract in respect to the payment of interest. The note stipulates for the payment of interest at the rate of eight per cent, per annum, and although it may not be paid until several years after it falls due, the payee is not entitled to interest upon the interest which has accrued at the date of maturity. The reason is that the parties having, by acquiescence extended the credit, the interest, which is an incident of the debt, goes with it and is not due at the maturity of the debt, so that an independent action for its recovery can be maintained. It is otherwise when the *314 nole contains an express promise to pay interest at specified times. At each time there is a certain sum of money due for which an action lies. “ When there is an agreement set out in the note for the payment of interest annually or semiannually, the maker is chargeable with interest at a like rate upon each deferred payment of interest, in like manner as if he had given a promissory note for the same amount. * * * By this mode of computation compound interest.is not given, but a middle course is taken between simple and compound interest.” Bledsoe v. Nixon, 69 N. C., 89; Knight v. Braswell, 70 N. C., 709; King v. Phillips, 95 N. C., 245; Cox v. Brookshire, 76 N. C., 314.

Such an agreement may be made either before or after the maturity of the debt; and when the principal debtor in this case agreed to pay the interest semi-annually, it so changed the original contract as to charge him with interest upon the interest accruing every six months thereafter, and this surely was such a benefit'to the plaintiff, the payee, as would support his promise to forbear.

It is insisted in this Court, though not distinctly passed upon below, that granting the consideration to be sufficient, the contract is nevertheless void because of its indefiniteness. It is true, as argued by counsel, that there must be a definite time fixed for the extension of credit; that is to say, there must be a time fixed before which the creditor cannot proceed against the principal debtor, but we think this is fully complied with by the agreement to pay the interest semi-annually. However indefinite it may be after the’first six months, it certainly 'amounts to an agreement to forbear for that period at least, and this is all that is necessary under our decisions to discharge the surety. In this we are sus-' tained by the following authorities: “An agreement to extend the time for twenty or thirty days is definite as to twenty days, and, therefore, discharges a surety.” 2 Daniel on Negotiable Instruments, § 1319. And so in Pipkin v. Bond, *315 5 Ired. Eq., 91, the surety was discharged, although the precise time fixed by the agreement could not be ascertained, the Court remarking that “as men of common sense, with even a very slight acquaintance with the common course of dealing, we are obliged to perceive that the parties understood that no suit should, at all events, be brought before the next term of Court.”'

In consideration of the foregoing reasons, we are of the opinion that the Court erred in instructing the jury that the testimony did not warrant an affirmative finding on the third issue.

As this disposes of the appeal, it is unnecessary to pass upon the question raised on the argument as to the effect of the alleged tender by the principal debtor. It is sufficient to say that the point is not raised, either by the answer or the issues.

Error.