The contract entered into between Hosley and the plaintiff is binding upon the defendant, as the successor of Hosley. They each represent the same principal, and the act of the former was within the power and authority vested in him, “ to contract with , and employ all teachers in the district school or schools.” (Laws of 1864, ch. 555, § 48, subd. 9.) There is not any limit, in terms, placed on the exercise of this power. It is also manifest, that to limit the right to employ a teacher, for a time not beyond the incumbent’s term of office, would lead, at times, to great embarrassments, and deprive *181the district of the opportunity to receive the services of desirable teachers. An indiscreet or corrupt officer may impose on the district, it is true. The inhabitants of the district and patrons of the school must confide this power somewhere, and their protection is in selecting competent and honorable officers.
The precise question has been adjudicated, and decided in favor of the power being vested in the trustee. (Silver v. Cummings, 7 Wend. 181. Williams v. Keech, 4 Hill, 168.)
Upon the question of damages, as presented by the defendant, in requesting the court to submit it to the jury, whether the plaintiff could not have obtained, by the exercise of due diligence, other employment of the same general character, in the same locality, the following rule, as stated in Hamilton v. McPherson, (28 N. Y. 72,) is justly applicable to cases of this nature: “ The law, for wise reasons, imposes upon a party subject to injury from a breach of contract, the active duty of making reasonable exertions to render the injury as light as possible.” “Public interest and sound morality accord with the law in demanding this; and if the injured party, through negligence of willfulness, allows the damages to be unnecessarily enhanced, the increased loss justly falls on him.” The duty thus imposed on a party subjéeted to a loss, by the default of another, utterly repudiates and condemns •the fallacious proposition, argued by the learned counsel for the plaintiff', that the plaintiff' was not required to make any effort to secure employment, as a teach’er, during the year of her engagement; but was only required to accept offers to teach made by those seeking her services. The violation of the contract by the defendant, and the plaintiff’s offer specifically to perform, prima facie, entitled the plaintiff to recover the contract price; and cast the burden of proof on the defendant, to show that, by reasonable exertion on her part, she could have obtained other like employment, in the vicinity of the place where *182she was to perform the contract entered into. This much can be deduced from the case of Costigan v. Mohawk and Hudson R. R. Co., (2 Denio, 609,) and nothing more, when compared with the many other previously adjudged cases, involving the same and kindred propositions. (Costigan v. The M. and H. R. R. Co., supra. Shannon v. Comstock, 21 Wend. 457. Heckscher v. McCrea, 24 id. 304.) It was the duty of the plaintiff to have made a reasonable exertion to secure another school, and not remain idle for a whole year, with folded arms, awaiting a call from other districts. To make a case for mitigating damages, the defendant was required to prove that, by making such efforts employment by the plaintiff could be secured.
In my opinion the evidence produced, by the defendant, on this point, as set forth in the bill of exceptions, was not of the character and strength, to entitle the defendánt to the opinion of the jury thereon. The substance of the statement is, that some of the schools in Salamanca and adjacent towns were not taken on the day the plaintiff was to enter upon the performance of the contract in question. The number of schools in these towns, wanting teachers, is not stated; nor how long the vacancies remained ; or that the plaintiff knew, or had reason to believe, that such opportunity to engage her services, as teacher existed. The court may- take judicial notice of the territorial extent of these towns, but beyond that, proof must be adduced, upon which to base and guide the judgment of the court and jury. . In many of the avocations of life, a year’s idleness would alone be sufficient evidence, that a person having control of his own time, had not used reasonable diligence to secure employment in his trade or calling. But teaching is a profession. In the country it is well known-, that the winter schools are usually taken as early as the middle of October, or very soon thereafter. The summer schools are very often entirely primary, and are perhaps such as an experienced and tal*183ented woman teacher, would not be required to accept and superintend, for the purpose of diminishing the damages of a party violating his contract.
The offer of the defendant to prove, in justification of ■ his official act, and in bar of a recovery, that the plaintiff was incompetent to teach the school, was improperly overruled by the learned judge at the circuit. The claim made, that the certificate of qualification was conclusive in her favor, is most decidedly erroneous. If she was in fact disqualified, then she could not perform her contract and discharge the delicate and important duties she had promised. Hor was the defendant required to allow her to make the experiment and prove, publicly, her unfitness. • A school teacher is, in a certain sense, a servant to the employer, and not an officer, of which the certificate granted by the commissioner is evidence of his right and qualification. The certificate is a sort of permit, that trustees of school districts may employ the holder to teach in the public schools.- Without such certificate they have no right to engage a person as teacher. With a person holding such certificate, they may make a valid contract binding on the district. There is nothing in Finch v. Cleveland (10 Barb. 290) holding to the contrary. (Laws of 1864, ch. 555, title 2, § 13, subd. 5.) By the provisions of another section, (title 1, section 15,) the State superintendent may grant certificates, and it is provided that such certificate shall be conclusive evidence that the person to whom it is granted is qualified, by his moral character, learning and ability, to teach any common school in the State. Ho such effect is given in terms to the certificate issued by a district commissioner. It is the uniform practice of the Department of Public Instruction, to hold that the certificate is not conclusive evidence of qualification, whenever that question is up, between the trustees and the teachers. The rulings of the department are collected and published in the Code of Public Instructions, pp. 393-403, ed. *184of 1868. These decisions are not strictly judicial, and binding on the courts as authority, but they are the opinions of high and intelligent officials, charged with the duty of administering an important department of the government. We concur in the comments of one of those officers, that “the license which the teacher holds from the proper officer is prima facie evidence, only, that the applicant possesses these requisites, but it is not conclusive; the presumption raised by it may be rebutted by direct evidence, tending to show that the holder of such license lacks any or all of these qualifications.”
[Fourth Department, General Term, at Buffalo, June 4, 1872.The trustee of a school district has no power to contract for the services of an unlicensed teacher, and bind the district. If he should make it a condition of hiring, that the teacher should procure a certificate before entering upon the duties of teaching, such contract would doubtless be valid, for. then the services of a licensed teacher are bargained for. (See title 2, § 13, subds. 5, 6; title 7, art. 6, § 48, subds. 9, 10; Laws of 1864, ch. 555; Code of Public Instructions, p. 140, ed. 1868.)
The bill of exceptions does not state whether the promise of the plaintiff to procure a certificate was a part of the written contract, or not. If it was not, the plaintiff cannot recover.
¡New trial granted; costs to abide the event.
Johnson, Talcott and Barker, Justices.]