As the principals, the contractors, signed the contract under seal, it is difficult to perceive the basis of the averment in the affidavit of defense, “ that this defendant is only liable for such debts as could be collected from ” the contractors. While it may be that the use plaintiff was too late to recover on Ms book account against the contractors, yet it is very clear that he could recover against them on this bond.

But independent of that the bond in suit is security for the debt to the use plaintiff, and like any other collateral is not *413released until the debt has been paid, though the right of action on the debt itself may be barred by the statute of limitations. After its limit has expired its own statute may of course be pleaded, but in the meantime the principal’s discharge is not available as a defense : Winton v. Little, 94 Pa. 64.

The bond is clearly intended as a sealed instrument by the appellant. It is signed in the name of the corporation by the vice-president, and the corporate seal is affixed, attested by the secretary. This is a very common, if not the usual, method of execution of sealed instruments by corporations. The fact that the seal is not opposite the president’s signature does not affect the plain intent of the instrument.

Judgment affirmed.