Mr. Justice McKenna,

after making the above statement,- . delivered the opinion of the court.

1. To sustain the motion to dismiss, it is contended that the jurisdiction of the case depends on diversity of citizenship, and hence that the judgment of the Circuit Court of Appeals is .final. But one of the defendants (plaintiff in .error), though a citizen of a different State from the plaintiff in the action *141 (defendant in error), is also a receiver of a national bank appointed by the Comptroller of the Currency and is an officer of the United States, and an action against him is one arising under the laws of the United States. Kennedy v. Gibson, 8 Wall. 498; In re Chetwood, 165 U. S. 443; Sonnentheil v. Christian Moerlein Brewing Co., 172 U. S. 401. It is, however, urged that such appointment was not shown. It was not explicitly alleged, but we think that it sufficiently appeared, and the motion to dismiss is denied.

2. Against the correctness of the action of the Circuit Court in instructing a verdict for the New York bank, it is urged that the discounting of the notes in controversy was for the personal benefit of Allis, and that the New York bank was charged with notice of it because of the nature of the transaction, the form of the notes and the order of the indorsements, and also because notice was a question of fact to be' decided by the jury on the evidence.

It is also contended that the receiver.was entitled to a judgment on the set-off. We will examine each of the propositions.

1. The argument to sustain this is that the facts detailed constitute borrowing money, and that borrowing is out of the usual course of legitimate banking business; and one who loans must at his peril see that the officer or agent who offers to borrow for a bank has special authority to do so. But is borrowing out of the usual course of legitimate banking business ?

Banking in much, if not in the greater part of its practice, is in strict sense borrowing, and we may well hesitate to condemn it as illegitimate, or regard it as out of the course of regular.business, and hence suspicious and questionable. “A bank,” says Morse, (sec. 2, Banks and Banking,) “ is an institution usually incorporated with power to issue its promissory notes intended to circulate as money (known as bank notes); or to receive the money of others on general deposit to form a joint fund that shall be used by the institution for its own benefit, for one or more of the purposes of making temporary loans and discounts; of dealing in notes, foreign and domestic *142 bills of exchange, coin, bullion, credits and the remission of money; or with both these powers, and with the privileges in addition'to these basic powers, of receiving special deposits •and making collections for the holders of negotiable paper, if the institution sees fit to engage in such business.”

This defines the functions: what relations are created by them ? Manifestly those of debtor and creditor — the bank being as often the one as the other.

A banker, Macleod says, is a trader who buys money, or money and debts, by creating other debts, which he does with his credit — exchanging for a debt payable in the future one payable on demand. This, he says, is the essential definition of banking. “ The first business of a banker is not to lend money to others but to collect money from others.” (Macleod on Banking, vol. 1, 2d ed. pp. 109, 110.) And Gilbart defines a banker to be “ a dealer in capital, or. more prop-, erly a dealer in money. He is an intermediate party between the borrower and the lender. He borrows of one party and lends to another.” (Gilbart on Banking, vol. 1, p. 2.)

The very first banking in England was pure borrowing. It consisted in receiving money in exchange for which promissory notes were given’payable to bearer on demand, and so essentially was this banking as then understood, that the monopoly given to the Bank of England was secured by prohibiting any partnership of more than six persons “to borrow, owe or take up any sum or sums of money on their bills or notes payable at demand.” And it had effect until 1772, (about thirty years,) when the monopoly was evaded by the introduction of the deposit system. The relations created are the same as those created by the issue of notes. In both a debt is created — the evidence only is different. In one ca$e it is a credit on the banker’s books ; in the other his written promise to pay. In the one case he discharges it by paying the orders (cheques) of his creditor ; in the other by redeeming his promises. These are the only differences. There may be others of advantage and ultimate effect, but with them we are not concerned.

But it may be said these views are elementary and do not *143 help to a solution of the question presented by the record, which is not what relation a bank has or what power its officers may be considered as having in its transactions with the general public, but what is its relation and what power its officers may be considered as having in its transactions with other banks. Indeed, the question may be even narrower — not one of power, but one of evidence. If so, the views expressed are pertinent. They show the basis of credit upon which banks rest, and the necessity of having power to support it; it may be to extend it. Borrowing is borrowing, no matter from whom. Discounting bills and notes may require rediscounting them; buying bills and notes may require selling them again. Money may not be equally distributed. It is a bank’s function to correct the inequality. The very object of banking is to aid the operation of the laws of commerce by serving as a channel for carrying money from place to place, as the rise and fall of supply and demand require, and it may be done by rediscounting the bank’s paper or by some other form of borrowing. Curtis v. Leavitt, 15 N. Y. 1; First National Bank v. National Exchange Bank, 92 U. S. 122; Cooper v. Curtis, 30 Maine, 488.

A power so useful cannot be said to be illegitimate, and declared as a matter of law to be out of the usual course of business, and to charge everybody connected with it with knowledge that it may be in excess of authority. It would seem, if doubtful at all, more like a question of fact, to be resolved in the particular case by the usage of the parties or the usage of communities.

It is claimed, however, that Western National Bank v. Armstrong, 152 U. S. 346, establishes the contrary, and decides the proposition contended for by the plaintiff in error. We do not think it does. Some of its language may seem to do so, but it was used in suggestion of a question which might be raised on the facts of the case, without intending to authoritatively decide it. The facts of that case are different from the facts of the pending one, and in response to its citation we might rest on the difference. But plaintiff in error urges the case so. earnestly and confidently that we have considered *144 it better to answer the argument on which it is asserted to be based and remove misapprehension of the extent of the decision.

2. Did the form of the notes or the order of indorsements charge the New York bank with inquiry of Allis’ authority or with knowledge of his use of them for his personal benefit ?

. It may be conceded that an individual negotiating for the purchase of a bill or note from one having it in possession, and whose name is upon it, must assume that the title of the holder, as well as the liability of all prior parties, is precisely that indicated by the paper itself.' ^ These principles are established by West St. Louis Savings Bank v. Shawnee County Bank, 95 U. S. 557; Central Bank of Brooklyn v. Hammett et al., 50 N. Y. 158; New York Iron Mine v. Negaunee Bank, 39 Michigan, 644; Lee v. Smith, 84 Missouri, 304; Park Hotel Co. v. Fourth National Bank, 86 Fed. Rep. 742; Claflin v. Farmers' & Citizens' Bank, 25 N. Y. 293.

But it is not meant-that circumstances may not explain the notes or may not relieve the taker from the obligation. of inquiry. If the order of indorsements and Allis’ official position and his relation to the notes were circumstances to be considered, they were not necessarily controlling against all other circumstances, and compelled inquiry as a peremptory requirement of law.

3. In judging of the conduct and rights of the New York bank the question is not what actual authority Allis had, but what appearance of authority he had, or, rather, what appearance of authority he was given or permitted by the directors.

In the inquiry there is involved the two preceding propositions as questions of fact, or of mixed law and fact. The first — the power of a bank to rediscount its paper — as to what the course of dealing of the contending banks was; the second — the form of the notes and their order of indorsements as notice — whether relieved by the circumstances which attended them and the transactions which preceded them.

The evidence shows that it was not only the custom of the defendant bank to rediscount its paper, but that it was *145 the custom of the other banks at Little Rock-to do so, and the officers of the New York bank testified as follows:

“Q. Were there any of the dealings between said banks (the parties to this action) other than such as take place between banks carrying on a legitimate banking business, in the usual course of business ?

“A. No.

“Q. Were the correspondence and transactions carried on by H. G. Allis and W. C. Denney, as you have disclosed, such as are usual for the president and cashier of a United States national bank to carry on and exercise ?

“A. Yes.”

This testimony certainly has very comprehensive scope, and there is no contradiction of it. It must be received, at least, as establishing that, as between the contending banks rediscounting paper was in the usual course of. their business, and that besides it was the usual course of business in their respective localities. Therefore the discounting of the notes in controversy carried the sanction of such business.

It is contended that- the notes gave notice of the want of authority to rediscount them because .the indorsement of the bank followed that of Allis, and hence showed that the bank was an accommodation indorser, and because the indorsement of the bank was by its president and not by its cashier.

The order of indorsements did not necessarily import that the Little Rock bank was an accommodation indorser. The order was a natural one if the' notes had been discounted in the regular course of business. It is not contended that a. want of power precluded the bank from discounting the notes of its officers. It had been done for one of the directors, and his note was rediscounted by the New York bank. It had an example therefore in the dealings of the parties, and, besides, was neither wrong nor unnatural of itself. But it was further relieved from question, and any challenge in the indorsements was satisfied by the circumstances.

It is to be remembered that the discounting the notes in controversy was not the only transaction between the banks. It was one of many transactions of the same kind. They *146 justified confidence, and it was confirmed by the manner in which the notes were presented. It is conceded that the cashier had the power to rediscount the bank’s paper, and it was he who solicited the accommodation on account of which the notes were sent to the New York bank. The notes themselves, it is true, were sent by Allis, but expressly on the part of the bank, and subsequent correspondence about them was conducted with the cashier, as we have seen. And there could have been no misunderstanding. The letter of the New York bank which the cashier of the Little Bock bank answered was specific in the designation of the notes, their sum and the proceeds of the discount, and returned one of the notes not in controversy to be corrected. To this the cashier replied:

“ Dec. 20, 1892.

United States National Bank, New York city.

Gentlemen: We have your favor of the 10th inst., enclosing the Dickenson Hardware Company note for completion, which we herewith return.

We charge your account with $31,871.27 proceeds of $32,500.00 of discounts.

Yours very truly, W. C. Denney, Cashier.”

Notice was therefore brought to him and to the bank of the transaction and almost inevitably of its items. Was he deceived as to the notes which had been sent? It is not shown nor is it suggested how such deception was possible, and a presumption of ignorance cannot be entertained. Therefore, if the discounts he wrote about in his letter of the 20th of December were not in pursuance of those he had requested in his letter of November 25, he ought to have known and ought to have so said. If he had so said, the New York bank could have withdrawn the credit it had given, and Allis’ wrong, could not have been committed.

The strength of these circumstances cannot be resisted. Against them it would be extreme to say that the New York bank was put to further inquiry. Of whom would it have inquired? Not of Allis, the president of the Littlq Bock *147 bank, because his authority would have been the subject of inquiry. Then necessarily of the cashier; but from' the cashier it had already heard. He began the transaction; he acknowledged its close, accepting the credit which had been created for the bank of which he, according to the argument, was the executive officer. We can discover no negligence on the part of the New York bank. The dealing with the notes in controversy came to it with the sanction of prior dealings with other notes. It was conducted with the same officers. It was no more questionable. The relation of Allis to it, we have seen, was not unnatural, and if the indorsement of other notes was not shown to be by him, it was not shown not to have been by him. The testimony of the officers of the New York bank was that the notes were received and discounted in the regular course of business, and in no way different from the other notes discounted by it for the Little Eock bank, and that they knew the notes were properly indorsed by one of the duly authorized officers of the First National Bank; but as the notes were not in their possession, they were unable to state the name of the officer. The testimony opposed to this, if it may be said to be opposed, is negative and of no value. Some of the directors testified that Allis did not have the power nor did they know of his having indorsed the bank’s paper for rediscount. They knew, however, that the bank’s paper was rediscounting in large amounts, and that money was borrowing continually, but they scarcely made an inquiry, and one of them testified that only in a single instance did Allis request the board for power to borrow money. The instance is not identified, except to say that it was in the fall of 1892. Of whom, in what amount, whether the request was granted or denied, what inquiry was made, what review of the business of the bank was made, there was absolute silence about. They surrendered the business absolutely to the president and cashier, and intrusted the manner of the execution to them. This court said by Mr. Justice Harlan, in Martin v. Webb, 110 U. S. 7, 15: “ Directors cannot, in justice to those who deal with the bank, shut their eyes to what is going on *148 around them. It is their duty to use ordinary diligence in ascertaining the condition of its business, and to exercise reasonable control and supervision of its officers. They have something more to do than from time to time to elect the officers of the bank and to make declaration of dividends. That which they ought by proper diligence to have known as to the general course of business in the bank, they may be presumed to have known in any contest between the corporation and those who are justified by the circumstances in dealing with its officers upon the basis of that course of business.”

Under section 5136, Revised Statutes, it was competent for the directors to empower the president or cashier, or both, to indorse the paper of the bank, and, under the circumstances, the New York bank was justified in assuming that the dealings with it were authorized and executed as authorized. Briggs v. Spaulding, 141 U. S. 132; Peoples Bank v. National Bank, 101 U. S. 181; Davenport et al. v. Stone, 104 Michigan, 521; First National Bank of Kalamazoo v. Stone, 106 Michigan, 367; Houghton v. The First National Bank of Elkhorn, 26 Wisconsin, 663; Thomas v. City National Bank of Hastings, 40 Nebraska, 501.

4. Set-off is the discharge or reduction of one demand by an opposite one. That of plaintiff in error was so applied and the amount due on the notes reduced. He was entitled to no other relief.

Scott v. Armstrong, 146 U. S. 499, does not apply. In that case it was held that a debtor of an insolvent national bank could set off against his indebtedness to the bank, which became payable after the bank’s suspension, a claim payable to him before the suspension. And it was further held that the set-off was equitable, and therefore not available in a common law action.

But in this case the plaintiff in error pleaded the set-off. His right to do so was derived from the law of Arkansas, and that law provided: “If the amount set off be equal to the .plaintiff’s demand, the plaintiff shall recover nothing by his action; if it be less than the plaintiff’s demand, he shall have *149 judgment for the residue only.” Gould’s Arkansas Digest of Statutes, c. 159, § 5, p. 1020. The law was complied with.

It follows that the Circuit Court did not err in instructing the jury to find for the plaintiff (defendant in error), and judgment is

Affirmed.