Mr. Justice Dunn

delivered the opinion of the court:

The appellee recovered a judgment against appellant for personal injuries, which the Appellate Court affirmed. Appellant has brought the record to this court for review.

The appellee was a postal clerk in the United States railway mail service, running between Peoria and Springfield over appellant’s railroad. His injuries were received while he was attending to his duties in the mail car attached to the appellant’s train, and were caused by a collision between that train and two coal cars which had run out upon appellant’s main track from a switch connecting such track with an adjoining coal mine. There was evidence tending to show negligence on the part of appellant’s servants in permitting the coal cars to come upon the main track.

The appellant claims that it is not liable because in carrying the mail, and the route agent in charge of it, the appellant was a governmental agency performing a governmental function, and was therefore not liable for the negligence of its employees. It further contends that plaintiff was ’not a passenger; that the highest duty it owed him was the exercise of ordinary care, and that the court erred in instructing the jury that it was appellant’s duty to do all that human care, vigilance and foresight could reasonably do to guard against accidents.

The first question arose upon appellant’s motion, at the close of all the evidence, to instruct the jury to return a verdict for the defendant. The switch track from which the coal cars came upon the main track was built and maintained by the railroad company at the mine company’s cost, and was used by appellant’s switching crews in taking the loaded cars from the mine for transportation. There was a derailing device in the switch track about one hundred and thirty-five feet from the main track which had no lock but could be opened or closed by any person, and it was due to the fact that this device was closed instead of open, as it should have been, that the accident occurred. It was therefore a question of fact whether, under all the circumstances, the appellant was negligent in guarding" its main track against cars coming upon it from the switch track, and this question was properly submitted to the jury, unless the appellant’s contention is sustained that it was engaged in the performance of a governmental function and therefore not liable for the negligence of its employees. Waiving the question whether the construction of the switch and derailing device in the manner in which they were constructed was not negligence of the appellant itself as distinguished from the negligence of its servants, the case will be considered as if the negligence which the evidence tended to prove were only negligence of the servants of appellant in the discharge of their duty.

The government of the United States has the power to establish post-offices and post roads, and has assumed exclusive charge of the carriage and delivery of the mail, prohibiting any private person from engaging" therein. In so doing the government is engaged in the discharge of a governmental function. The- principle is well recognized that public officers and agents of the government are exempt, as such, from liability to answer for the acts of their subordinates. They are liable for their own personal negligence or defaults in the discharge of their duties but. not for the acts or defaults of inferior officials in the public service, whether appointed by them or not. (Robertson v. Sichel, 127 U. S. 507.) The appellant, however, is not a public officer or a public agent. It is a contractor with the government for the performance of a special service, viz., the carrying of the mail, and the same reason does not exist for holding it exempt from liability- for the negligence of its servants as for holding the post-master general or a post-master exempt from liability for the defaults of those who act under them in the public service, as agents of the government. “The responsibility óf a public officer for the acts and defaults of those employed by or under him depends upon the question whether such persons are acting in the public service, as agents of the government, by direct appointment or by authorized sub-appointment, or whether they are his private agents and servants employed by virtue of his individual and independent authority and paid by and responsible to him, whom he can employ, retain and dismiss at will, ‘in other words, whether the situation of an inferior is a public office or a private service.’ (I Am. Lead. Cas. 785.) If the subordinates are the agents and servants of the officer, not by an official employment but to assist him, as an individual, in the discharge of his official service, the reason ceases for the non-application of the doctrine of respondeat superior and for exemption from liability for their misconduct or negligence.” Central Railroad and Banking Co. v. Lampley, 76 Ala. 357.

The case just cited was a suit brought by a bank against a railroad company for the loss from the mail of money contained in a registered letter through the negligence of the servants of the company, and it was held that the company would be liable in a proper form of action. In the case of Sawyer v. Converse, 17 Graft. 230, the Supreme Court of Virginia, after a thorough consideration of the exemption of public officers and agents from responsibility for the acts and defaults of those employed by or under them in,the discharge of their public duties, and an examination of the decided cases, held a mail contractor liable to the sender for the loss from the mail, through negligence of the contractor’s servant, of a letter containing money.

The exemption of public officers from responsibility for the negligence or positive wrongs of their subo-dinates in the discharge of their, public duties arises from considerations of public policy. Competent persons would not be willing to accept positions which imposed upon them liability for torts and wrongs committed by subordinates whom they did not appoint and could not discharge. These considerations do not apply to a corporation undertaking, by contract, to perform work or render service for the government for a compensation to be paid to it and with a view to its own profit, and where its subordinates are employed and paid by it and liable to be dismissed at its pleasure. It is said in Sawyer v. Converse, supra: “Such a contractor is in no just and proper sense an officer of the government, and though he may be said to be in a certain sense an agent of the government because he is engaged in working for the government, yet the laborers and others whom he employs under him in the execution of his contract cannot be said to be agents of the government, which does not know them, does not appoint them, does not control them, does not pay them and has nothing to do with them.' He is not a public agent, because he is working for his own profit by fulfilling a contract which he has bound himself to perform and for which he is to receive compensation.”

The maxim of respondeat superior is founded on the principle that he who expects to derive advantage from an act which is done by another for him must answer for any injury which another may sustain from it. We know of no reason why it should not apply here. The employees of the appellant were not public officers or in any official service or employment. They were not employed for the special service of transporting the mails, but were the private servants of appellant engaged in the work of appellant in the general business of transportation for its benefit and profit, employed by appellant and subject to be discharged at its pleasure. It does not appear that the servants of the appellant by whose negligence the injury to appellee is claimed to have occurred were even incidentally-engaged in any way in the transportation of the mails.

Several cases have been cited which have held that a mail contractor is not liable for the loss of property transmitted by mail and lost through the carelessness of the contractor’s servants. They are Conwell v. Voorhees, 13 Ohio, 526, Hutchinson v. Brackett, 22 N. H. 252, Boston Ins. Co. v. Chicago, Burlington and Quincy Railroad Co. 118 Iowa, 423, and Banker’s Mutual Casualty Co. v. Minneapolis, St. Paul and Sault Ste. Marie Railway Co. 117 Fed. Rep. 434. These cases proceed upon the theory that mail contractors are public agents and not responsible for the omissions, negligence or misfeasance of those employed by them. We think the cases which hold the contrary are supported by the sounder reason. No case has been cited holding that a railroad company is not liable for an injury caused to a postal clerk by the negligence of its employees while in the mail car in the performance of his duties. There are numerous decisions that they are so liable to the same extent as to a passenger for hire. Malott v. Central Trust Co. 168 Ind. 428; Seybolt v. New York, Lake Erie and Western Railroad Co. 95 N. Y. 562; Mellor v. Missouri Pacific Railroad Co. 105 Mo. 455; Gulf, Colorado and Santa Fe Railway Co. v. Wilson, 79 Tex. 371; Libby v. Maine Central Railroad Co. 85 Me. 34; Lindsey v. Pennsylvania Railroad Co. 26 App. Cas. (D. C.) 563; Collett v. London and Northwestern Railroad Co. 16 A. & E. (N. S.) 984; 71 E. C. L. 984.

It is insisted that the appellant could not be compelled, as a common carrier, to transport the mail, but that its contract to do so was a mere private contract which did not impose upon it any liability as a common carrier to the appellee, since it was under no common law or statutory obligation to carry him in the manner he was carried at the time of the accident. The appellee was lawfully on the train, to be carried by the appellant for a consideration received by it under its contract with the government as its compensation for carrying the mail and the person in charge of it. Under such circumstances the law imposes upon the railroad company the duty of carrying- safely, and the degree of care required is commensurate with the dangerous consequences likely to result from negligence. Whether or not, in a strict sense, the relation- of carrier and passenger exists between the railroad company and the postal clerk, courts hold with substantial unanimity that a postal clerk upon a railway train is entitled to the same measure of care as an ordinary passenger for hire. He has as good a right to be upon the train as the ordinary passenger and his life is just as valuable. The moral duty to exercise care to avoid injuring him is the same, and no valid reason exists for a distinction in the legal duty. The rule that requires the exercise of the utmost care and vigilance to guard against accident extends to every case in which a carrier receives and agrees to transport another not in its employment, whether by contract with the person to be carried or with some other person b)r whom the person to be carried is employed for the purpose of transacting the employer’s business upon the cars or other conveyances of the carrier. In case the person so to be carried is injured through the- negligence of the carrier or its servants, without his fault, his right to recover damages rests upon the same basis as that of an ordinary passenger for hire. Recoveries have been had on this basis in many other cases besides those already cited. The principle has been applied to postal clerks, express messengers, persons riding on a drover’s pass, and persons permitted to conduct a business on a public conveyance by arrangement with the carrier. Gleeson v. Virginia Midland Railway Co. 140 U. S. 435; Nolton v. Western Railroad Co. 15 N. Y. 44; Blair v. Erie Railway Co. 66 id. 313; Brewer v. New York, Lake Erie and Western Railroad Co. 124 id. 59; Pennsylvania Co. v. Woodworth, 26 Ohio St. 585; Baltimore and Ohio Railroad Co. v. State, 72 Md. 36; Decker v. Chicago, Milwaukee and St. Paul Railway Co. 102 Minn. 99; Illinois Central Railroad Co. v. Crudup, 63 Miss. 291; Grant v. Raleigh and Gaston Railroad Co. 108 N. C. 462; Hammond v. Northeastern Railroad Co. 6 S. C. 130; Louisville and Nashville Railroad Co. v. Kingman, 35 S. W. Rep. (Ky.) 264; Norfolk and Western Railroad Co. v. Shott, 92 Va. 34; Commonwealth v. Vermont and Massachusetts Railroad Co. 108 Mass. 7; Yeomans v. Contra Costa Steam Navigation Co. 44 Cal. 71; New York, Chicago and St. Louis Railroad Co. v. Blumenthal, 160 Ill. 40; Cavin v. Southern Pacific Co. 136 Fed. Rep. 592; Railroad Co. v. Lockwood, 17 Wall. 375; Yarrington v. Delaware and Hudson Co. 143 Fed. Rep. 565; Jennings v. Grand Trunk Railway Co. 15 Ont. App. 477; 3 Thompson on Negligence, secs. 2649-2651; 2 Hutchinson on Carriers, (3d ed.) secs. 1017, 1018.

In Pennsylvania it has been held that the right of action of a postal clerk for injuries received while being carried in the mail car is only such as would exist if he was an employee of the railroad company, and does not stand on the same footing as that of a passenger. (Pennsylvania Railroad Co. v. Price, 96 Pa. 256; Foreman v. Pennsylvania Railroad Co. 195 id. 499.) But those decisions are based upon the construction of a statute of Pennsylvania. They hold that “passengers,” as used in that statute, were intended to be distinguished from persons “lawfully engaged or employed on or about the roads, works, depots and premises of a railroad company, or in or about any train or car therein or thereon, of which company such person is not an employee,” and that postal clerks are included within the latter class as distinguished from passengers. Those cases are therefore not in conflict with the doctrine of the other cases cited.

We have held that a railroad company, in contracting with an express company for the transportation of express matter and the company’s messengers in charge thereof, may require an exemption from liability for the negligence of its employees, and that a contract made by the messenger with the express company in consideration of his employment, assuming all risk of injury in the course of his employment, occasioned by the negligence of the railroad company, and releasing- the railroad company from liability to him therefor, was not against public policy but would be enforced. (Blank v. Illinois Central Railroad Co. 182 Ill. 332.) The same rule has been applied to a like contract made by a sleeping car porter. (Chicago, Rock Island and Pacific Railway Co. v. Hamler, 215 Ill. 525.) The principle on which these cases were decided is, that the railroad company is not bound to receive and haul over its road express cars or sleeping cars or to furnish to the owners of such cars facilities for carrying on their business on its railroad. It may undertake to do so, but if it does, the undertaking is not the performance of a duty imposed by law but is a special contract, giving rights which, as a common carrier, it could not be compelled to grant. The principle is announced in numerous decisions of other courts but is not applicable here. There was no release of the appellant’s liability, either by the appellee or by the government. Even if it be conceded that the appellant was not a common carrier as to the appellee and that the appellee was not, a passenger, yet appellant was liable to the appellee for negligence to the same extent as to a passenger, and the fact that his contract to release the appellant from liability would have been valid is not important unless he actually made a contract to release it. The trial court therefore did not err in instructing the jury as to the measure of care required of the appellant.

The judgment of the Appellate Court is affirmed.

Judgment affirmed.