One L. M. Lester, the owner of a stock of general merchandise in the town of Winona, insured it with the plaintiff, a corporation engaged in the fire insurance business, in the sum of $2,000, which was less than its value. On August 3, 1907, the property was totally destroyed by fire which, it is alleged, originated through the negligence of the defendant company. The plaintiff paid Lester the amount of the insurance and, by articles of subrogation, took an assignment of his claim against the defendant to the extent of the amount paid. The defendant, at and before the date of the fire, was operating a steam railroad which passed through the town of Winona, where it owned and maintained a depot, depot platforms, and other buildings. The goods were stored in a frame building near the depot. Winona is situated at the junction of defendant’s main line of road, which runs easterly and westerly at that point, and its Pleasant Valley road, which runs northerly. The depot and coal house were between the two lines of road and near the switch. *334The coal house was some fifty feet northeast of the depot, and the store about the same distance northwest of the coal house. A platform extended around the depot and within about a foot of the ties of each line of road.
About midnight of August 2, 1907, a fire was observed in the depot platform a few feet distant from the main line of track on the south side of the depot, which communicated to the depot and coal house and thence to the building containing the stock of merchandise, completely destroying the store and its contents. The case was tried upon the issues in the second amended complaint and the answer. The negligence charged is that, at the time of the fire, the defendant had stored a large quantity of giant powder, with fulminating explosive caps, in the coal house; that the fire originated from ashes and cinders containing live embers, which the defendant had taken from its engines and deposited on the main fine track a few feet from the depot platform; that the fire communicated from the platform and depot to the coal house, causing the giant powder and caps to explode with such violence as to shatter and destroy the building, throwing fire brands upon, and setting fire to, the store building. It is also alleged that, before the commencement of the action, Lester settled with the defendant for the loss he had sustained in excess of the sum paid him by the plaintiff on the policies. A general demurrer to this complaint was overruled. The defendant joined issue on the charges of negligence, admitted that it had settled with Lester, but denied that the settlement was made before the suit was commenced. At the close of the plaintiff’s testimony, the defendant challenged its sufficiency and moved for a dismissal of the case, and at the close of all the evidence, it moved for a directed verdict. From a verdict and judgment for $2,000 in favor of the plaintiff, the defendant has appealed.
The first error suggested is, that the respondent did not own the entire cause of action when the suit was commenced; that there was but one wrongful act, and that but one suit *335can be maintained; that there being no evidence to support the allegation that Lester settled with the appellant before the commencement of the action, there is a failure of proof, and the case should^have been withdrawn from the jury at the close of the respondent’s testimony. The following authorities are cited in support of this contention: Continental Ins. Co. v. Loud & Sons Lumber Co., 93 Mich. 139, 53 N. W. 394, 32 Am. St. 494; Home Mut. Ins. Co. v. Oregon R. & Nav. Co., 20 Ore. 569, 26 Pac. 857, 23 Am. St. 151; State Ins. Co. v. Oregon R. & Nav. Co., 20 Ore. 563, 26 Pac. 838; Fireman’s Ins. Co. v. Oregon R. & Nav. Co., 45 Ore. 53, 76 Pac. 1075, 67 L. R. A. 161; Wunderlich v. Chicago & N. W. R. Co., 93 Wis. 132, 66 N. W. 1144; Mobile Ins. Co. v. Columbia & G. R. Co., 41 S. C. 408, 19 S. E. 858, 44 Am. St. 725; Norwich Union Fire Ins. Society v. Standard Oil Co., 59 Fed. 984; Watts v. Southern Bell Tel. & Tel. Co., 66 Fed. 453; Southern R. Co. v. Blunt & Ward, 165 Fed. 258; Dietz v. Winehill, 6 Wash. 109, 32 Pac. 1056; German Fire Ins. Co. v. Bullene, 51 Kan. 764, 33 Pac. 467. We think the point is not well taken. As we have seen, the answer admits that the appellant has settled with Lester. When that fact was disclosed, it was apparent that the respondent owned the entire cause of action. It is, therefore, not material whether the settlement occurred before or after the action was commenced.
The appellant argues that, when the complaint discloses that all the parties in interest have not united as plaintiffs, a cause of action is not stated. We think it would present a case of a defect of parties plaintiff. If the appellant’s view is correct, in the absence of evidence that the settlement was made with Lester before the action was commenced, it was the duty of the court to withdraw the case from the jury; for it is fundamental that, where a cause of action does not exist when the action is commenced, but arises thereafter, that fact cannot be shown either by an amended or supplemental pleading. The office of an amended complaint is to correctly *336state a cause of action that existed when the action was commenced, and the office of a supplemental complaint is to state a breach of a legal right connected with the subject of the action and arising after the action was commenced. The record presents a case where the owner of a part of the cause of action became the sole owner during the pendency of the action by the voluntary act of the co-owner and the party against whom the cause of action was asserted.
The cases cited by the appellant all state the rule that a claim or demand arising out of a single transaction, whether resting in contract or tort, cannot be divided into separate and distinct claims so that separate and independent actions can be waged upon the several parts. The reason for the rule is that a party against whom there exists but one liability cannot be vexed by a multiplicity of suits by the same or different parties for the breach of a single duty. Stated in another form, a party cannot be permitted, even in a tort, to split a cause of action and bring separate actions for a part of the claim, or several actions where one would suffice. The complaint discloses but one wrongful act, causing but one loss, creating, but one liability, and the record shows that the respondent is the entire owner of that liability. In most of the cases cited, the record discloses that others who were not parties still owned an interest in the cause of action. None of the cases cited present the precise question before us. In German Fire Ins. Co. v. Bullene, supra, the court remarked :
“If we could say from the record brought here that this case alone was pending against the insurance company, and that all of the parties in any manner interested in the policy were before the court, so that the rights of each and all of them could be fully determined, it might be that the plaintiff’s judgment could be upheld.”
At any time before Lester settled he could have been united as a plaintiff, and all the parties in interest would have been before the court. The same thing was accomplished when he *337settled with the appellant. To hold that his settlement defeated the right of the respondent to proceed with the case would be sacrificing substance to form. The cause of action was not then split, but was in the respondent in its entirety. Davis v. Seattle, 37 Wash. 223, 79 Pac. 784, is in point. In that case a married woman commenced an action in her own name to recover for personal injuries. The original complaint did not disclose that she was a married woman, but that fact appeared from her evidence. At the close of her testimony, the adverse party moved for a judgment on the ground that the husband was a necessary party. She was then permitted to amend her complaint and unite her husband as a party plaintiff. On appeal this was urged as error, and it was contended that she had no cause of action and that she could not amend and make her husband, the party having the cause of action, a party plaintiff after the submission of all her evidence. It was held that the wife suing alone could not recover, but that it was not error to permit the amendment.
The respondent offered testimony tending to show that it was the custom of the appellant to clean the ashes and cinders from the engine on the main line track south and southwest of the depot and within a few feet of the platform, and to permit them to remain there;.that they had frequently set fire to the cross ties; that the wind was blowing from the southwest at the time of the fire, and that the fire when first observed was in the platform on the south side of the depot a few feet from the main line track. A Mr. Broyles, a watchman and engine cleaner in the employ of the appellant at Winona, testified that no engines were cleaned on the main line or near the depot during the day or evening preceding the fire; and a Mr. Ely, a fireman on the main line, testified that engines were not cleaned at Winona. The appellant’s second contention is that the presumption arising from the evidence of appellant’s custom of cleaning its engines and the occurrence of other fires at that point, was overcome by its direct evi*338dence, and that it was error for the court to submit that issue to the jury.
We think the point is without merit. If the respondent’s evidence is true, the appellant had many times been guilty of the grossest negligence. The question of the veracity and credibility of the appellant’s witnesses was one of fact for the jury to determine. It might properly have concluded that, in. view of the appellant’s past conduct, the course of the wind, and the location of the fire when first observed, the memory of the appellant’s witnesses was defective, or that they did not truthfully relate the facts. The fire occurred, as we have stated, in August, 1907. The trial was had in December, 1908. The jury was the tribunal designated by the constitution to try the facts. The circumstances related by the appellant’s witnesses were of sufficient cogency to carry the case to the jury upon this issue. Ireland v. Scharpenberg, 54 Wash. 558, 103 Pac. 801; McCullen v. Chicago & N. W. R. Co., 101 Fed. 66, 49 L. R. A. 642. The authorities cited by the appellant are spark cases, and are so different upon the facts that they are not in point.
The learned trial court correctly instructed the jury upon the law applicable to the case. Finding the record free from error, the judgment is affirmed.
Rudkin, C. J., Fullerton, and Morris, JJ., concur. Chadwick, J., took no part.