Mr. Justice Brewer delivered the opinion of the court:

On February 19, 1903, the legislature of the state of Oregon passed an act (Session Laws 1903, p. 148) the first section of which is in these words:

'Sec. 1. That no female (shall) be employed in any mechanical establishment, or factory, or laundry in this state more than ten hours during any one day. The hours of work may be so arranged as to permit the employment of females at any time so that they shall not work more than ten hours during the twenty-four hours of any one day.'

Sec. 3 made a violation of the provisions of the prior sections a misdemeanor subject to a fine of not less than $10 nor more than $25. On September 18, 1905, an information was filed in the circuit court of the state for the county of Multnomah, charging that the defendant 'on the 4th day of September, A. D. 1905, in the county of Multnomah and state of Oregon, then and there being the owner of a laundry, known as the Grand Laundry, in the city of Portland, and the employer of females therein, did then and there unlawfully permit and suffer one Joe Haselbock, he, the said Joe Haselbock, then and there being an overseer, superintendent, and agent of said Curt Muller, in the said Grand Laundry, to require a female, to wit, one Mrs. E. Gotcher, to work more than ten hours in said laundry on said 4th day of September, A. D. 1905, contrary to the statutes in such cases made and provided, and against the peace and dignity of the state of Oregon.'

A trial resulted in a verdict against the defendant, who was sentenced to pay a fine of $10. The supreme court of the state affirmed the conviction (48 Or. 252, 85 Pac. 855), whereupon the case was brought here on writ of error.

The single question is the constitutionality of the statute under which the defendant was convicted, so far as it affects the work of a female in a laundry. That it does not conflict with any provisions of the state Constitution is settled by the decision of the supreme court of the state.

It is the law of Oregon that women, whether married or single, have equal contractual and personal rights with men. As said by Chief Justice Wolverton, in First Nat. Bank v. Leonard, 36 Or. 390, 396, 59 Pac. 873, 874, after a review of the various statutes of the state upon the subject:

'We may therefore say with perfect confidence that, with these three sections upon the statute book, the wife can deal, not only with her separate property, acquired from whatever source, in the same manner as her husband can with property belonging to him, but that she may make contracts and incur liabilities, and the same may be enforced against her, the same as if she were a feme sole. There is now no residuum of civil disability resting upon her which is not recognized as existing against the husband. The current runs steadily and strongly in the direction of the emancipation of the wife, and the policy, as disclosed by all recent legislation upon the subject in this state, is to place her upon the same footing as if she were a feme sole, not only with respect to her separate property, but as it affects her right to make binding contracts; and the most natural corollary to the situation is that the remedies for the enforcement of liabilities incurred are made coextensive and coequal with such enlarged conditions.'

It thus appears that, putting to one side the elective franchise, in the matter of personal and contractual rights they stand on the same plane as the other sex. Their rights in these respects can no more be infringed than the equal rights of their brothers. We held in Lochner v. New York, 198 U.S. 45 , a law providing that no laborer shall be required or permitted to work in bakeries more than sixty hours in a week or ten hours in a day was not as to men a legitimate exercise of the police power of the state, but an unreasonable, unnecessary, and arbitrary interference with the right and liberty of the individual to contract in relation to his labor, and as such was in conflict with, and void under, the Federal Constitution. That decision is invoked by plaintiff in error as decisive of the question before us. But this assumes that the difference between the sexes does not justify a different rule respecting a restriction of the hours of labor.

In patent cases counsel are apt to open the argument with a discussion of the state of the art. It may not be amiss, in the present case, before examining the constitutional question, to notice the course of legislation, as well as expressions of opinion from other than judicial sources. In the brief filed by Mr. Louis D. Brandeis for the defendant in error is a very copious collection of all these matters, an epitome of which is found in the margin. While there have been but few decisions bearing directly upon the question, the following sustain the constitutionality of such legislation.

The legislation and opinions referred to in the margin may not be, technically speaking, authorities, and in them is little or no discussion of the constitutional question presented to us for determination, yet they are significant of a widespread belief that woman's physical structure, and the functions she performs in consequence thereof, justify special legislation restricting or qualifying the conditions under which she should be permitted to toil. Constitutional questions, it is true, are not settled by even a consensus of present public opinion, for it is the peculiar value of a written constitution that it places in unchanging form limitations upon legislative action, and thus gives a permanence and stability to popular government which otherwise would be lacking. At the same time, when a question of fact is debated and debatable, and the extent to which a special constitutional limitation goes is affected by the truth in respect to that fact, a widespread and longcontinued belief concerning it is worthy of consideration. We take judicial cognizance of all matters of general knowledge.

It is undoubtedly true, as more than once declared by this court, that the general right to contract in relation to one's business is part of the liberty of the individual, protected by the 14th Amendment to the Federal Constitution; yet it is equally well settled that this liberty is not absolute and extending to all contracts, and that a state may, without conflicting with the provisions of the 14th Amendment, restrict in many respects the individual's power of contract. Without stopping to discuss at length the extent to which a state may act in this respect, we refer to the following cases in which the question has been considered.

That woman's physical structure and the performance of maternal functions place her at a disadvantage in the struggle for subsistence is obvious. This is especially true when the burdens of motherhood are upon her. Even when they are not, by abundant testimony of the medical fraternity continuance for a long time on her feet at work, repeating this from day to day, tends to injurious effects upon the body, and, as healthy mothers are essential to vigorous offspring, the physical well-being of woman becomes an object of public interest and care in order to preserve the strength and vigor of the race.

Still again, history discloses the fact that woman has always been dependent upon man. He established his control at the outset by superior physical strength, may, without conflicting with the provisions and this control in various forms, with diminishing intensity, has continued to the present. As minors, thought not to the same extent, she has been looked upon in the courts as needing especial care that her rights may be preserved. Education was long denied her, and while now the doors of the schoolroom are opened and her opportunities for acquiring knowledge are great, yet even with that and the consequent increase of capacity for business affairs it is still true that in the struggle for subsistence she is not an equal competitor with her brother. Though limitations upon personal and contractual rights may be removed by legislation, there is that in her disposition and habits of life which will operate against a full assertion of those rights. She will still be where some legislation to protect her seems necessary to secure a real equality of right. Doubtless there are individual exceptions, and there are many respects in which she has an advantage over him; but looking at it from the viewpoint of the effort to maintain an independent position in life, she is not upon an equality. Differentiated by these matters from the other sex, she is properly placed in a class by herself, and legislation designed for her protection may be sustained, even when like legislation is not necessary for men, and could not be sustained. It is impossible to close one's eyes to the fact that she still looks to her brother and depends upon him. Even though all restrictions on political, personal, and contractual rights were taken away, and she stood, so far as statutes are concerned, upon an absolutely equal plane with him, it would still be true that she is so constituted that she will rest upon and look to him for protection; that her physical structure and a proper discharge of her maternal functions-having in view not merely her own health, but the well-being of the race-justify legislation to protect her from the greed as well as the passion of man. The limitations which this statute places upon her contractual powers, upon her right to agree with her employer as to the time she shall labor, are not imposed solely for her benefit, but also largely for the benefit of all. Many words cannot make this plainer. The two sexes differ in structure of body, in the functions to be performed by each, in the amount of physical strength, in the capacity for long continued labor, particularly when done standing, the influence of vigorous health upon the future well-being of the race, the self-reliance which enables one to assert full rights, and in the capacity to maintain the struggle for subsistence. This difference justifies a difference in legislation, and upholds that which is designed to compensate for some of the burdens which rest upon her.

We have not referred in this discussion to the denial of the elective franchise in the state of Oregon, for while that may disclose a lack of political equality in all things with her brother, that is not of itself decisive. The reason runs deeper, and rests in the inherent difference between the two sexes, and in the different functions in life which they perform.

For these reasons, and without questioning in any respect the decision in Lochner v. New York, we are of the opinion that it cannot be adjudged that the act in question is in conflict with the Federal Constitution, so far as it respects the work of a female in a laundry, and the judgment of the Supreme Court of Oregon is affirmed.