Opinion of the Court. 1880 and on the 22d of December, 1881, partial payments of interest were made on the note by Thomas Cross, or in his interest. The second note was dated January 23, 1872, payable in one year, and consequently matured January 26, 1873. The bar of the statute on this note would have been complete January 26, 1879, had no interest been paid upon it in the meantime. It is averred in the bill and admitted in the answer that the interest on this note was paid in full up to January 25, 1879, one day before the completion of the bar; and another payment of interest was made February 1, 1883. This suit was commenced August 6, 1884. Consequently it is to be observed that there never was a period of six years between the making of either note and the bringing of this suit that no payments were made upon them. Section 25 of the Code of Civil Procedure of Oregon provides as follows: "Whenever any payment of principal or interest is made on an existing contract, whether it be bill of exchange, promissory note, bond or other evidence of indebtedness, after the same becomes due, the limitation shall commence from the time the last payment was made." It is conceded that the payments of interest above referred to served to keep the debt alive, so far as the principal was concerned; but it is argued that they did not do so with reference to the surety, Pluma F. Cross, or her estate, especially in view of the fact that she died before the maturity of either note, and also in view of the fact that she never signed the notes at all, but became a legal surety by reason of having signed the mortgages. This presents a question worthy of much consideration. At common law, a payment made upon a note by the principal debtor before the completion of the bar of the statute, served to keep the debt alive, both as to himself and the surety. Whitcomb v. Whiting, 2 Doug. 652; Burleigh v. Stott, 8 B. & C. 36; Wyatt v. Hodson, 8 Bing. 309; Mainzinger v. Mohr, 41 Michigan, 685. That is the rule in many of the States of this Union — in all, in fact, where it has not been changed by statute. National Bank of Delavan v. Cotton, 53 Wisconsin, 31; Quimby Opinion of the Court. v. Putnam, 28 Maine, 419. At common law and in those of the States where the common law rule prevails, a distinction is made between those cases in which a part payment is made by one of several promisors of a note before the statute of limitations has attached and those in which the payment is made after the completion of the bar of the statute; it being held in the former that the debt or demand is kept alive as to all, and in the latter, that it is revived only as to the party making the payment. Atkins v. Tredgold, 2 B. & C. 23; Sigourney v. Drury, 14 Pick. 387, 391; Ellicott v. Nichols, 7 Gill, 72, 85, and cases cited. The reason of this distinction lies in the principle that, by withdrawing from a joint debtor the protection of the statute, he is subjected to a new liability not created by the original contract of indebtedness. There is. no statute of Oregon, so far as we have been able to discover, changing the common law rule of liability with reference to sureties. Consequently, under the admitted facts of this case, it must be held that the statute of limitations of the State never operated as a bar to the enforcement of the original demands against both the principal and the surety. Nor do we think the death of the surety before either of the demands matured makes any difference, in principle, where, as in this case, the liability is not of a personal nature, but is an incumbrance upon the surety's property. We are aware that there is authority holding that payment of interest by the principal debtor, after the death of the surety, but before the statute of limitations has run against the note, will not prevent the surety's executors from pleading the statute. Lane v. Doty, 4 Barb. 530; Smith v. Townsend, 9 Rich. (S. C.) Law 44; Byles on Bills, sec. 353; 2 Parsons on Notes and Bills, 659, and note t. But we know of no authority extending this rule to the representatives of a deceased surety whose liability was not personal but upon property mortgaged. On the contrary, the cases of Miner v. Graham and Bank of Albion v. Burns, supra, seem to recognize the doctrine which we are inclined to accept. We conclude, therefore, that the contract of suretyship in this case was not terminated by the death of the surety before the maturity of the indebtedness. Opinion of the Court. The question of laches and staleness of claim virtually falls with that of the defence of the statute of limitations. So long as the demands secured were not barred by the statute of limitations there could be no laches in prosecuting a suit upon the mortgages to enforce those demands. The mortgage is virtually a security for the debt, and an incident of it. Ewell v. Daggs, 108 U. S. 143. And it is immaterial that the failure to sue upon the demands may have resulted injuriously to the surety, so long as there was no variation in the original contract of suretyship, either as respects a new consideration or a definite extension of time; since it is a familiar principle of law that the mere omission or forbearance to sue the principal without the request of the surety will not discharge the surety. 1 Parsons on Notes and Bills, 236, 238, and notes. Did the conveyance by Cross to Lewis of the lands mortgaged and the subsequent transactions in relation thereto, before set out, amount to an extension of time for a definite period, or vary the terms of the original contract of suretyship? We think not. In this connection we are not unmindful of the rule that any material change in the contract on which he is a surety, made by the principal parties to it, without his assent, discharges the surety, even though he may be benefited by such change; the reason being that he has not assented to the contract in its altered form, and has a right to stand upon the very terms of his undertaking. Reese v. United States, 9 Wall. 13, 21; 1 Parsons on Notes and Bills, 239. But in this case there was no extension of time for a definite period, no new consideration passed, nor was there any material alteration of the terms of the original contract. The rights of the surety remained the same after those transactions as they were before. The transactions in this matter were at farthest a more convenient method of enforcing payment of the original demand, and possibly may be considered as amounting to an additional security. But that is all. Even that would not release the surety. 1 Parsons on Notes and Bills, 245, and notes. The mortgage security was not lessened at all, for the net proceeds arising from the sale of those portions of the property on which the mortgages were released Opinion of the Court. were applied to the diminishing of the debt. That property, too, seems to have been sold for more than its appraised value, and there is nothing in the record to show that, under the circumstances of the case, it was worth any more. True, the record states that there are five persons who would testify that in 1876 it was worth fifty per cent more than it was sold for. But as was well remarked by the court below, it is not to be expected that mortgaged property, when sold on account of the default of the debtor, will bring what it would at ordinary private sale; and if the five persons mentioned had been asked what the property sold would have brought, under such circumstances, it may be they would not have differed much from the appraised value of it. There does not seem to have been any fraud whatever in this whole transaction. In fact, none is charged. The sales were made with the assent of the owner, Thomas Cross, were open and without concealment or deception, and were for a fair value. The whole affair bears the impress of good faith, and we are not warranted in saying it was otherwise. The only remaining question is, whether, under the constitution and laws of Oregon in force at the time these contracts were made, a married woman could, in any event, bind her separate property for the payment of her husband's debts. Without discussing this question upon the merits, it is sufficient to say that the Supreme Court of the State has decided it in the affirmative in at least two separate cases, Moore v. Fuller, 6 Oregon, 272, 274, and Gray v. Holland, 9 Oregon, 512; and it is not our province to question such construction. Being a construction by the highest court of the State of its constitution and laws, we should accept it. It is said, however, that the cases just cited were decided without having been fully argued and without mature consideration of this question, upon the mistaken assumption that it had been previously decided in the affirmative by the Supreme Court of the State, and, therefore, they have not become a rule of property in the State and are not binding upon this court. We are not impressed with this contention. Such argument might with propriety be addressed to the Supreme Opinion of the Court. Court of the State, but it is without favor here. We are bound to presume that when the question arose in the state court it was thoroughly considered by that tribunal, and that the decision rendered embodied its deliberate judgment thereon. There are no other questions in the case that call for especial consideration, as the foregoing virtually disposes of all of them. Upon the whole case we are of the opinion that the decree of the court below was correct, and it is Affirmed. The CHIEF JUSTICE and MR. JUSTICE GRAY did not hear the argument or take part in the decision of this case. ADAMS v. BELLAIRE STAMPING COMPANY. ERROR TO THE CIRCUIT COURT OF THE UNITED STATES FOR THE SOUTHERN DISTRICT OF OHIO. No. 50. Argued October 26, 1891.- Decided November 16, 1891. The alleged invention protected by letters patent No. 50,591, granted October 24, 1865, to John H. Irwin, was a combination of old devices, each performing its old function and working out its own effect, without producing anything novel as the result of the combination, and was not patentable. When the sole issue in an action for the infringement of a patent is as to the patentable character of the alleged invention, it is not error to decline to instruct the jury that the fact that the machine had practically superseded all others was strong evidence of its novelty. THE case is stated in the opinion. Mr. J. H. Raymond for plaintiff in error. Mr. Lysander Hill for defendant in error. MR. JUSTICE FIELD delivered the opinion of the court. This is an action to recover damages for the alleged infringement of a patent for an improvement in lanterns, granted to |