This is a direct appeal from the circuit court for the district of North Dakota, sustaining the constitutionality of a statute of that state, requiring the manufacturers of mixed paints to label the ingredients composing them.

The statute is as follows:

An Act to Prevent the Adulteration of and Deception in the Sale of White Lead and Mixed Paints.

Be it enacted by the legislative assembly of the state of North Dakota: 1. Every person, firm, or corporation who manufactures for sale or exposes for sale, or sells, within this state, any white lead paint or compound intended for use as such, shall label the same in clear and distinct open gothic letters upon a white background, and show the true per cent of each mineral constituent contained in said paint, or, if other than linseed oil is used in its preparation, the names of such oils or substitutes shall be shown, together with the percentage thereof, and every person, firm, or corporation who manufactures for sale, or exposes for sale, or sells within this state, any mixed paint or compound intended for use as such which contains any ingredient other than pure linseed oil, pure carbonate of lead, oxid of zinc, turpentine, Japan dryer, and pure colors, shall be deemed guilty of a misdemeanor, and upon conviction thereof shall, for each offense, be punished by a fine of not less than twenty-five and not more than one hundred dollars and costs, or by imprisonment in the county jail not exceeding sixty days; provided, that any such person, firm, or corporation, who shall manufacture for sale, or expose for sale, or sell within this state any white lead paint or mixed paint, containing ingredients other than those as above enumeroated, shall not be deemed guilty of a violation of this act in case the same be properly labeled showing the quantity or amount of each and every ingredient used therein and not specified above, and the name and residence of the manufacturer or person for whom it is manufactured.

It is made the duty of the appellee, in his official capacity, to enforce the statute. A few days before the statute took effect (January 1, 1906), the appellants filed a bill to restrain its enforcement, and prayed a preliminary as well as a permanent injunction. A preliminary injunction was granted. It was dissolved on final hearing, and a decree was entered, dismissing the bill for want of equity.

The grounds of attack upon the statute are that it offends against the 14th Amendment of the Constitution of the United States, in that it deprives appellants of their property and liberty without due process of law, and denies them the equal protection of the laws. How it is contended the statute produces these effects will be pointed out hereafter.

The stress of the case is upon paragraph 17 of the bill and the special paragraphs 'A' and 'B.' To these paragraphs an answer was filed. The legal effect of the others was submitted upon demurrer. Upon the issue of fact formed by the answer to paragraph 17 and the special paragraphs, testimony was taken, and upon it and the demurrer to the other allegations, and the affidavit of one Professor Ladd, the case was submitted.

The bill is voluminous. It alleges that the plaintiffs are manufacturers of mixed paints, and sell their respective products in North Dakota, and that each 'had established an enviable reputation for its goods;' that each sold in North Dakota mixed paints containing ingredients other than those specified in the statute, which is set out. It is alleged that mixed paint has an absolutely defined meaning in the trade, and means a paint so thinned, 'by admixture of the proper liquid vehicles, as to reduce it to a consistency which makes it ready for use.' The term mixed paint, it is alleged, is used in contradistinction to 'a paste paint,' which paint has also a well defined meaning, meaning a paint ready for use, except that it requires thinning material to give it the necessary consistency. White lead, it is alleged, is a commercial, not a scientific, term, and is commonly understood to be a dry powder consisting of commercial carbonate of lead. When ground in oil to a paste consistency it is commonly called in the trade white lead in oil, colloquially referred to frequently as 'white lead.' In the statute these terms are used interchangeably, and are intended to denote white lead in oil, as above defined. That various compounds containing no carbonate of lead or other ingredients in addition to carbonate of lead are frequently sold in the market labeled as 'white lead.' And that the words 'any white lead paint, or compound intended for use as such,' in the act, 'are intended to denote a paste paint, intended as a substitute for white lead, and labeled or sold as 'white lead' or 'white lead in oil,' but which does not contain any carbonate of lead, or contains other ingredients in addition thereto.' Paragraph 17 is as follows:

'Your orators further show unto your honors that the manufacture of paint, and more particularly of mixed paint, involves many practical problems, the proper solution of which demands the application of a variety of scientific principles, and is the result of a great variety of practical tests and experiments; that the means, methods, and processes employed in said manufacture have changed materially in the course of years to conform to the discovery of new scientific facts and the results of practical experiments; that the technology of paint manufacturing has made gradual and constant progress during the last fifty years, during which time it has undergone an evolutionary process which is still far from completed; that until about twenty-five years ago carbonate of lead was the only material which was universally conceded by manufacturers and users of paint to be a proper pigment to be used in paints requiring or admitting of the use of a white pigment; that since said time, and within the last twenty-five years, oxid of zine gradually gained recognition among manufacturers and users of paint as being equally appropriate for the purposes for which theretofore carbonate of lead had alone been recognized as appropriate, and has come to be universally conceded as possessing important useful qualities as a white pigment not possessed by carbonate of lead; that within the last fifteen years practical experiments and tests, made with a view to widening the range of white pigments properly usable in the manufacture of paint, have demonstrated the following facts, which are now conceded by the most advanced and most successful paint manufacturers of the world, viz.:

'a. That there are materials other than carbonate of lead and oxid of zinc which, in some cases, may be used in connection therewith and in other cases may be used instead thereof, and which, either without carbonate of lead or oxid of zinc, or in connection with one or both of these, according to circumstances, are as efficient as, and in some respects more efficient than, carbonate of lead or oxid of zinc, or a combination of the two, for the purposes for which the latter are used in paint; that among said materials are (a) sublimed lead (which is an artificial product consisting of sulphate of lead and oxy-sulphate of lead), (b) standard zinc lead white (which is commonly called zinc lead, and is an artificial product, made by the United States Smelting Company, and sold in large quantities, and consists of a combination of sulphate of lead and oxid of zinc united by a furnace process), (c) zinc made from Western ores, which carries in its natural composition varying proportions of sulphate of lead and oxid of zinc, and (d) an artificial opaque white pigment, consisting essentially of zinc sulphid, zinc oxid, and barium sulphate, which is known to the paint manufacturing trade under various trade names, such as lithopone, ponolith, lithophone, charlton white, becton white, and Orr's white.

'b. That there are certain white pigments other than carbonate of lead and oxid of zinc which constitute proper and useful ingredients of paints, and which, if so used in connection with carbonate of lead or oxid of zinc, or a combination of the same, or in connection with one or more of said other materials described in the last preceding paragraph as proper substitutes for carbonate of lead and oxid of zinc, furnish to the paint wherein used important useful qualities not possessed by either carbonate of lead or oxid of zinc, or any of said substitutes therefor; that among said other pigments are sulphate of barium, silica, silicate of magnesia, calcium carbonate, hydrated sulphate of lime, and others; that the proportionate amount of the pigments last named which may properly and usefully be made an ingredient of paint, and whether any of them may be properly used as such ingredients, depends upon a great variety of conditions and circumstances, but all of said pigments may, under proper conditions, serve a highly useful purpose, and where properly used do essentially increase the durability and density of the paint.'

It is further alleged that the statute, in condemning inferentially the use of the materials mentioned in paragraph 17 and its subparagraph, 'as ingredients of mixed paint, and branding them as adulterants, ignores the fact that all said substances constitute proper, useful, and necessary ingredients of paint, is based upon antiquated, obsolete, and quite generally discarded prejudices regarding the ingredients proper, useful, and necessary to be used in paint, and is therefore unreasonable and void.'

That complainants and most of the successful paint manufacturers of the United States have for many years maintained, and continue to maintain, in connection with their factories, chemical laboratories, wherein in are able, accomplished chemical experts, who are constantly conducting experiments in the qualities and properties of new ingredients to produce the best results regarding the purposes of paint, the materials upon which it is used, and the various conditions to which it may be exposed. And that the business success of such manufacturers largely depends upon the efficiency of said laboratories and experiments, 'and their readiness and ability to conform their methods of manufacturing to the truths discovered by said investigations and tests.' That such experiments have led to the adoption of improved methods of manufacture and the use of a widening range of ingredients and a constantly increasing degree of efficiency in the paint produced, and, if continued, 'is sure to bring about a still higher and gradually increasing degree of merit and efficiency in the paint of the future.'

Other allegations of the bill set forth the virtues and usefulness of varnish as a vehicle or thinning material of mixed paint in connection with or in place of one or other of the ingredients of the statute for some purposes and situations, and that the statute, by excluding it, brands it as an adulterant, and is hence void. The bill also charges the statute with inaccuracy in its designation of pure carbonate of lead as one of the ingredients of mixed paint specified, and alleges that it cannot be used for the purpose of manufacturing paint, and that the carbonate of lead which is commonly used and has been used from time immemorial, even in paints of the higher grade, contains approximately 20 to 30 per cent of other ingredients. It is hence charged that the statute, by specifying 'pure' carbonate of lead, and prohibiting as a crime the use of commercial carbonate of lead, 'without specifying on a label quantity or amount of each of its ingredients, is unreasonable and void.' The bill also attacks with much detail the term 'pure colors' in the enumeration of the ingredients by the statute, alleges that such term neither has a definite meaning among the manufacturers of such coloring material nor among manufacturers of paint, nor is it capable of an exact, or even an approximately exact, definition; that there is no line of demarcation between pure and impure colors; that while some dry colors are regarded as 'pure' and others 'impure' by some manufacturers, there is nothing approaching a consensus of opinion upon the subject, and no rational classification has been attempted; that the standard universally applied to dry colors is not purity, but efficiency; that, with the exception of a very few dry colors of limited use in mixed paints, even the very highest and most expensive grades made or imported contain large and widely varying percentages of elements which have no coloring properties. Illustrations are given, and the bill charges 'that said act, in specifying 'pure colors' among the ingredients of mixed paint, and making the use of any but 'pure colors' as such ingredient a crime, unless the manufacturer or dealer stigmatizes the paint by a label, as required in said act, is so uncertain and unreasonable as to be void.'

It is also alleged that the only purposes for which paint is used is to preserve and beautify, and that that paint is most efficient which accomplishes those purposes for the longest time, and that any ingredient which tends to such ends is a proper ingredient; that there is no natural standard of the purity of paint, nor a widely-accepted standard; that any enumeration of allowable ingredients, short of an exhaustive enumeration of ingredients which may, under particular circumstances and conditions, give to paint a useful quality, is necessarily unjust and unreasonable, and even such enumeration, though just to-day, by discoveries may be unjust to-morrow; that, to produce an efficient paint, not the ingredients alone must be considered, but the manner and the proportion of every combination, and the purpose and conditions of the use of the paint; that it is, therefore, impossible to speak of a standard of purity as applied to paint, 'nor is it reasonable for any statute to attempt to set up a standard of efficiency of paint by an enumeration of allowable ingredients; the only test of the efficiency of paint being its ability to serve the purposes for which it is intended.'

It is further alleged that the requirement of the statute 'is intended and calculated to create in the minds of the mixed paint dealers and consumers in the state of North Dakota the erroneous belief that all ingredients of mixed paint other than those specified in said act are adulterants, used for the purpose of cheapening the product, and add no quality of usefulness or efficiency to the mixed paint wherein they are used; that said act, in requiring mixed paint containing any ingredients other than those specified in said act as aforesaid, to be labeled as aforesaid, is a requirement that the manufacturer of and dealer in such paint shall brand the same in such a way as to hold it up to the suspicion and prejudice of the users of mixed paint, and thereby make the sale thereof in said state, if not impossible, at least more difficult and expensive.'

That the excluded ingredients (they are enumerated in the bill) will have no tendency by their use to render 'mixed paint by those applying the same harmful to health in any sense or degree.' That while such act was intended as a police regulation for the prevention of fraud, its provisions are such that it has no tendency to accomplish such end; that the act, by failing to specify the maximum and minimum of the proportionate amount of the ingredients specified, permits the manufacture and sale of mixed paint containing those ingredients in such proportions as to make it absolutely inefficient and useless and a fraud upon the purchaser; that by holding up to the prejudice of dealers in and users of other mixed paint has the tendency, in many instances, to give inferior brands a preference over superior brands of mixed paint. And that such act has no tendency to accomplish the prevention of fraud, because it does not prevent the manufacture and sale 'of any imaginable paint concoction in paste form,' or impure linseed oil, or any spurious article, as 'white lead,' or 'white lead in oil,' or as 'white lead paint,' because a paint ready for use may be lawfully made of such concoctions and substitutes; 'that the manufacture and sale of paste paint is a substantial part of the paint manufacturing and selling business of the United States; that millions of dollars worth of white lead in oil and compounds intended as substitutes therefor are annually manufactured and sold in the United States; that tinting colors for use as an ingredient of paint are manufactured in large quantities and sold in cans, in paste form, throughout the United States; that linseed oil, as such, is an article of commerce throughout the United States;' and that the statute, by failing to place restriction on the manufacture or sale of such paint and material, but imposing penalties and restrictions on the manufacturers of mixed paint, unjustly discriminates against the latter, and, for the same reason and 'the other facts and circumstances' stated in the bill, they will be deprived of their property without due process of law.

It was also alleged that each of the complainants manufactures 'scores of different kinds and shades of mixed paints, differing from each other in chemical composition; that even the same kind and shade of mixed paint manufactured by any one of your orators has no fixed chemical composition, but varies in such composition from time to time and practically with each lot manufactured, by reason of the wide variations in the chemical composition of the constituent ingredients, more especially the chemical composition of the dry colors used; that in order to properly label the cans of mixed paint manufactured by your orators, and sold in North Dakota, showing 'the quantity or amount of each and every ingredient used therein, and not specified' in said act, each of your orators would have to have a chemical analysis made of each lot of mixed paint before putting the same up in cans or other containers.' It is alleged that this would add materially to the cost of manufacture of mixed paints, cast a burden upon them from which the manufacturers of other paints are free, and would deprive them of their property without due process of law.

It is further alleged that there are dealers in North Dakota who have on hand a stock of mixed paint subject to the act, and who will be subject to criminal prosecution unless the cans containing the same be opened and analyzed and labeled, which opening would make the paint unsalable; that dealers, who, in the future, shall purchase from any of the complainants, and the distributing agents and salesmen of complainants, will be subject to criminal prosecution; and thereby a multiplicity of criminal prosecutions will ensue, and suits to enforce payments for paints sold or to be sold. And if the complainants should label the mixed paints manufactured by them as required by the act they would not only be subject to the expense thereof, but that their products will be held up to suspicion and prejudice of the dealers in and users of the same, which will make it either impossible or more difficult and expensive to sell their products in said state, all of which will produce incalculable and irreparable injury to complainants; that the dealers in paints who are now subject or may be subject to prosecution under such act will not have sufficient interest to or cannot successfully raise the defense of the invalidity of the act, 'inasmuch as such defense involves the consideration of the complex state of facts hereinbefore set forth.'

Fear is expressed that most of such prosecutions will result in conviction, and that by such the brands of mixed paints involved therein will be branded as adulterated and illegal products, and will thereby be rendered unsalable, all of which will produce incalculable and irreparable injury to complainants, and will constitute the taking of their property without due process of law and the denial to them of the equal protection of the laws.

It is difficult to separate the admissions and denials of the answer to paragraph 17. It admits that practical problems are involved in the manufacture of paints, particularly of mixed paints, the solution of which is the result of a variety of practical tests and experiments; 'that the technology of paint manufacture has made gradual and constant progress during the past fifty years, during which time it has undergone an evolutionary process. 'It admits that formerly carbonate of lead was the only material which was universally used as the proper pigment in paints requiring or admitting of the use of a white pigment, and that oxid of zinc has gained recognition as in many cases appropriate as a white pigment, but denies that such recognition has come within the last twentyfive years; on the contrary, asserts it has been recognized and used for a period of thirty years. Admits that there are materials other than carbonate of lead and odix of zinc used in connection with the latter or instead of them, but denies their equal efficiency; on the contrary, alleges that tests and experiments have not determined or demonstrated the value and usefulness of such materials, and further alleges that their use and value have not progressed beyond the experimental stage. That about one half of the leading manufacturers entirely reject them, or reject them because, upon test, they have proved to be unsatisfactory and inefficient, and others, that time has not yet demonstrated their value. Admits that zinc made from Western ores is valuable and efficient as a pigment, provided sulphate of lead, incidental to its production, does not exceed in quality 5 per cent of its constituent elements, and alleges that the percentages of the sulphate of lead are widely different.

The answer to subparagraph 'b' of paragraph 17 admits that in making the colored paints there mentioned it is necessary to employ some of the articles mentioned in connection with some pigment other than carbonate of lead, and that the latter would change or modify the exact shades sought to be produced. But it is alleged on information and belief that the aggregate of all mixed paints produced, sold, and consumed in North Dakota, in the preparation of which it is necessary to exclude carbonate of lead, and to include one or more of the substituted materials mentioned in the bill, does not exceed 25 per cent of the aggregate of all mixed paints which may be prepared and produced by the use alone of carbonate of lead and oxid of zinc as pigments. Save as to those admitted, the answer denies the efficiency of the materials mentioned, and avers that the general use of them is 'to cheapen and adulterate the paints wherein they are employed,' and, of all substances known, they are best adapted and lend themselves most readily and are commonly used as adulterants to cheapen mixed paints. It is further averred that 70 to 75 per cent of the paint used in the state are mixed paints, and that their adulteration has become and is a great evil. 'That no other substances have been discovered or known, which, by their inherent qualities, lend themselves so readily to, or are so commonly employed for, such purpose of fraud and deception, as those described in said subparagraph 'b."

Messrs. Sigmund Zeisler and Henry L. Stern for appellants.

[Argument of Counsel from pages 349-352 intentionally omitted]

Messrs. John S. Watson, T. S. McCue, and Ball, Watson, Young & Hardy for appellee.

Mr. Justice McKenna delivered the opinion of the court: