Plaintiff is the widow of George Timson, deceased, who was a coal miner in the employ of defendant in its coal mine at or near Connelsville, Missouri. In this mine were employed a large number of men. Deceased came to his death by a rock falling from the roof of the mine upon him. The date of the accident was July 19, 1905.
*588The petition was in two counts, the first being bottomed upon sections 8802 and 8820, Revised Statutes 1899, and the second under sections 2865 and 2866, Revised Statutes 1899. , The second count need not be considered here, as the recovery was had under the first count. Section 8802 is the foundation of the action in the first count, and following the tenor of the statute the petition charges “that it became and was the duty of the defendant to have said mine examined every morning by a practical and duly authorized agent of defendant to determine whether there were any obstructions to roadways and entries or any other dangerous .conditions in said mine, and not to permit any one to enter said mine until the examiner should report all the conditions safe for beginning work,” and then in appropriate language avers a failure upon the part of the defendant to perform the duty thus required by the statute, and that by such neglect of duty the deceased came to his death, and prayed for damages in the sum of ten thousand dollars.
The answer was a general denial, to which was coupled a plea of assumption of risk.
The petition does not aver that the coal mine in question was a mine in which gas was generated, but said first count is a clear attempt to state a cause of action under the statute, supra.
For the purpose of this opinion, in the view we take of the law, full details of the evidence is not required. Verdict and judgment was for plaintiff in the sum of $7,000' and from this judgment, after a timely but futile motion for a new trial, the defendant appealed.
Plaintiff offered no proof of the fact that the mine in question generated gas. Otherwise, the proof offered by plaintiff tended to show a failure upon the part of the defendant to perform the duties required of it by this statute, and that the death of the deceased was occasioned by such failure. It will not be nec*589essary to advert to defendant’s evidence further than it bears upon disputed questions of law here. This evidence will be noted in the course of the opinion when discussing such disputed questions.
I. Upon the cross-examination of some of the witnesses for the plaintiff the defendant sought to elicit the fact that the miners’ union of which deceased was a member dominated the business of'the defendant in the employment of men to operate its mine. The plaintiff objected to the introduction of this evidence upon the ground that no such issue was tendered by the pleadings, and this objection was by the court sustained. After this defendant offered to prove that said miners’ union, of which deceased was a member, dictated to defendant whom it should employ and whom it should not employ; what wages it should pay; what hours the men should work; that without the consent of such miners’ union the defendant did not dare to discharge an employee or employ a man; that the men (including deceased) in the mine of defendant were virtually employed by this union of which deceased was a member, and for that reason deceased was not in law or fact in the employ of defendant when killed. This offer of proof was rejected for the same reason by the court, and all this is urged as error by defendant.
Under the pleadings there was no error in this action of the court. If it was the purpose of the defendant to show that by- some species of duress it had been forced to employ the deceased, and that the deceased, individually or by and through his fellow members of the miners’ union, had coerced his employment, then this question should have been raised by appropriate pleading. If the employment was not made by the defendant voluntarily, but by duress, and the defendant seeks to avail itself of such matter, it should have raised it upon proper plea. A general *590denial is- not sufficient to raise this kind of an issue. Duress when relied upon to defeat a contract is an affirmative defense, and must he specially pleaded. [7 Ency. Plead. & Prac., 247; Pomeroy’s Code Pleading (4 Ed.), 990; Chitty on Pleading (16 Ed.), 511; Richardson v. Hittle, 31 Ind. 119 ; Ins. Co. v. McCormick, 45 Cal. 580; Lord v. Lindsay, 18 Hun (N. Y.) 484.]
So too, we take it, that if the defendant relies upon the fact that the relationship of master and servant had been created by duress, the same rule of pleading would apply. As to whether or not this pleading and this proof would be a proper defense to the action, we are not now called upon to determine. It is sufficient to say that in the present shape of the pleadings there can be no question as to the correctness of the ruling. The other exceedingly interesting question we reserve for a time when it becomes a live issue in a concrete case.
II. By questions to witnesses and otherwise in the course of the trial the defendant tried to prove that the mine in question did not, as a matter of fact, generate gas. This evidence was rejected by the trial court on the ground that the court would take judicial notice or cognizance of the fact that all coal mines generate gas. In this position the court' was in error, but was evidently lead into such error by the bolding of the Kansas City Court of Appeals in the case of Poor v. Watson, 92 Mo. App. 89. This opinion ia wrong and is overruled. It is wrong for several reasons: First, the section of the statutes under whicli this suit was instituted contemplates that as to gases there are two classes of coal mines, i. e., gas-generating mines and non-gas-generating mines. The term gas as used here means such gas as renders the mine dangerous to the health and limb of the miner, and further such quantities as to make it dangerous. To gel *591at the meaning of the Legislature we must get at the contest of the law passed at the time, as well as the previous legislative enactment upon the subject. Section 8802, whilst not specifically mentioning coal mines, had its origin in the Act of April 9’, 1895. [Laws 1895, pp. 228 and 229.] It there appears as section 7064a. In this act there are sis sections, numbered respectively 7064, 7064a, 7064b, 7064c, 7064d, and 7064e, which were carried into the Revised Statutes of 1899 as sections 8801 to 8806, inclusive. Of this act four out of the sis sections speak of coal mines in terms, and the last section (now Sec. 8806, R. S. 1899), reads:
“Every owner, agent or operator of any coal mine, in this State, employing five or more persons, violating any of the provisions of sections 8801 to 8805, inclusive, shall be deemed guilty of a misdemeanor, and on conviction shall be fined for each offense not less than fifty or more than two hundred dollars, or by imprisonment in the county jail not less than three nor more than twelve months, or by both such fine and imprisonment.”
The last section of the act shows conclusively that the Legislature was legislating as to coal mines and coal mines only. This is so because when it came to penalizing violations of the sections, including the section under consideration, the Legislature mentions operators of coal mines and none others.
If the section relates solely to coal mines then why use the Words “all mines generating gas” in section 8802 if the Legislature did not recognize that there were some coal mines which did not generate gas? Neither article of chapter 133, Revised Statutes 1899, came into our statutes by way of a revised bill, and to get the real legislative intent we must go to the contest of the act of which the section formed a part at the time of the enactment. [Paddock v. Railroad, 155 Mo. 524.]
*592But even had there been a revised bill passed, yet under section 4189, Revised Statutes 1899, these sections would have continued and remained separate laws. Said section reads: “All acts of a general nature revised and amended and re-enacted at the present session of the General Assembly, so soon as such acts shall take effect, shall be taken and construed as repealing all prior laws relating to the same subject, but the provisions of the Revised Statutes, so far as they are the same as those of prior laws, shall be construed as a continuation of such laws and not as new enactments.” This section is identical in language with section 6606, Revised Statutes 1889, and in the Paddock case, supra, in discussing section 6606, supra, this court said: “Sections 2590 and 2591, as also sections 2593 to 2597, inclusive, of the Revised Statutes 1889, as above shown, are exactly the same as the laws of March 31st and March 23d, respectively, and therefore those sections must be treated, under this legislative direction, as mere continuations of those laws and not as new enactments. They were entirely different laws before and they continued to be different notwithstanding they were carried into the Revised Statutes and placed in the same article of the same chapter of the Revised Statutes, and notwithstanding that they may appear in the bill enacted by the Thirty-fifth General Assembly- which revised chapter 42. This has been the uniform ruling of this court on this question. [St. Louis v. Alexander, 23 Mo. 483; City of Cape Girardeau v. Riley, 52 Mo. loc. cit. 428; State ex rel. Atty.-Genl. v. Heidorn, 74 Mo. 410; Pool v. Brown, 98 Mo. loc. cit. 680.] ”
So that we find the Act of 1895, of which the present section 8802 was a part, related solely to coal mines, and if so the Legislature evidently classed coal mines as gas-generating and non-gas-generating mines, for if not why put the section in its present form? Had • the Legislature known, as counsel *593■would have us say, , that all coal mines generated gas, it would have simply provided for the inspection of all mines or all coal mines, without undertaking to create a class of coal mines by use of the words “all mines generating gas.” The use of these words in the connection therein used shows that the lawmaking branch recognized that there were coal mines which did not generate gas of a kind and character and in quantity to make it dangerous to the health and safety of the miners. The Act of 1895 cannot be read without the conclusion being drawn that each section therein has reference to coal mines and coal mines only.
The act itself having in effect divided coal mines into gas-generating mines and non-gas-generating mines, no cause of action is stated under section 8802, without an allegation that the particular mine in question was a mine generating gas. Nor could a case be made without proof of that fact.
And, secondly, aside from the fact that the Legislature has classified coal mines, as above indicated, they are likewise classified by nature.
Whether a mine is gas-generating is dependent upon many circumstances. By “gas-generating” we mean the generating of gas of such kind and in such quantity as will imperil either life, limb or health of the miner, for such we take to be the legislative meaning. The depth of the mine is a factor.' Whether a wet or dry mine is a factor. The character of the coal contained in the mine is a factor. (See Vol. 6, p. 72, Encyclopedia Brittanica, as to gas-producing character of different kinds of coal.) Conditions produced in the working of a mine may be a factor, as when large amounts of dry fine dust are allowed to accumulate, or decaying organic matter is permitted to remain in the mine. The dangerous gases appear in some mines and not in others.
*594In McKinnon v. Coal & Mining Co., 120 Mo. App. l. c. 161, it is said: “It stands admitted that the mine in question did not generate gas.”
But under the ruling of Poor v. Watson, supra, if we were trying a case from that mine in Barton county, we would take judicial notice of a- fact which did not exist. In volume 4 of the Encyclopedia Americana, under the head of Coal Mining, we find: “The principal gases found in coal mines are carhon dioxide, Co2, heavier than air, suffocating but not inflammable, called choke-damp by miners; carbon monoxide, CO, about as heavy as air, poisonous and inflammable, but easily detected by its odor. Of these gases, marsh gas, given off in large quantities in some mines, is the chief agent in coal mine explosions. A mine is said to be fiery when the coal seems to fire off much fire-damp. Many of the deeper coal mines of Great Britain, France, and Germany, are very fiery. The most fiery mines in the United States are in the anthracite region of Pennsylvania, the South Wilkes-Barre shaft at Wilkes-Barre being one of the most fiery mines in the world. A mixture of marsh, gas and air in certain portions explodes violently on contact with flame. Coal dust in the air makes a much smaller proportion of marsh gas an explosive mixture.”
• In the Twelfth Annual Report of our State Mine Inspectors (1898) we find an extended discussion of gases in mines. On page 29, it is said: “No coal mine is absolutely free from gas, although all mines do not give off the same kind of gas; one mine will discharge carbonic acid gas (called by the miners ‘black-damp’), while another mine in which a large amount of powder is used, or when spontaneous combustion occurs, resulting from the gobs taking fire and generating carbonic oxide or white gas; still other mines give off a carburetted hydrogen gas, which is known to the miners as ‘fire-damp.’ All of the gases encountered in coal mines are evolved from the coal and its as*595sociated strata, and the prime object in modern mine ventilation is to remove the gas by air currents, or so dilute it as to render it harmless.”
It will be observed that different mines produce different gases, and this is due, as will be seen by reading the article, from different causes or conditions. The gas most generally found in coal mines is carbonic acid gas, or in the miners’ vernacular “black-damp.” Of this the writer on page 31, says: “Black-damp is a non-supporter of combustion, it is invisible, incombustible, odorless and colorless, unfit for respiration, and a positive poison, and is produced in mines by the decaying of organic matter, by burn-. ing of lights, by the respiration and perspiration of' men and animals, and in connection with carbonic oxide from the combustion of all substances containing carbon, and sometimes it enters in large quantites from; fissures in the floor, roof and sides of the mine.”
It thus appears that this gas may come from two sources. If it comes from the first mentioned in the article above quoted, the generation thereof and the amount thereof can be regulated or prevented entirely by keeping the mine in proper condition, viz., by keeping out decaying organic matter, and by proper ventilation removing the conditions produced by burning lights, respiration by men and animals. But if it enters through fissures in the floor, roof or sides of the mine, and is not produced by the conditions first aforesaid we would have a mine actually generating gas, which could only be regulated by good and strong air circulation. Of inflammable gases we are informed that only two counties in the State (Bates and Linn) have mines which produce such. Upon investigation, I find that officers having charge of the enforcement of our mining statutes, i.e., the State Mine Inspectors, have always construed section 8802 to apply to mines generating inflammable gases and not otherwise.
*596But take the mine in question, how can we take judicial knowledge of the fact that it produces gas of any particular kind, and was so producing it at the date of the accident? So far as we know there might have been no fissures in the floor, walls and sides . giving forth gas, because all mines do not have such, and it may have been so cleared of rubbish and other matter by proper ventilation and otherwise, as not to produce gas from the other sources.
In an early work, entitled, “Coal, Iron & Oil,” by Daddow and Bannan, at page 304, it is said: “As no gases are liberated in working the coal, the means of ventilation are simple. The main object kept in view is to conduct a sufficient supply of pure air through the mine in order to displace the vitiated air where the miners are at work. This is accomplished by natural means, the currents of air being produced by the difference of density between the air of the mine and that of the atmosphere, motion being communicated by the difference in altitude between the mine-shaft and the mouth of the adit or gangway.”
But beyond all it is not a matter of common knowledge that gas of some kind is generated in deleterious quantities in all coal mines, and it is only of matters of common knowledge that we take judicial cognizance. To this should be added scientific facts which universal experience has reduced to common knowledge.
As said in 16 Cyc. 852: “Courts may properly take judicial notice of facts that may be regarded as forming part of the common knowledge of every person of ordinary understanding and intelligence; but not of facts merely because they may be ascertained by reference to dictionaries, encyclopedias, or other publications; nor of facts which the court cannot know without resort to expert testimony or other proof.”
The case of Poor v. Watson, 92 Mo. App. 89, relied upon by my brother, is wrong and should be *597overruled in terms upon this point. The cases cited and relied upon by the learned judge writing the opinion in that case do not go to the extent of his opinion. In every case cited the thing judicially noticed is a thing of common knowledge. It may be that all experienced coal miners have a peculiar knowledge of the gas-generating proclivities of coal mines, but we cannot go so far as to hold that it is so universally known and a matter of such common knowledge as to make it a subject of judicial cognizance.
III. When testimony was offered to show that the mine did not generate gas at the time of the accident, the objection made was, “Because the law presumes all coal mines to some extent to generate gas.” This objection was sustained. This was error. If there is any question about the matter of taking judicial notice of a fact the doubt should be solved against the assumption of such fact and the parties put upon their proof. A very learned author, with much reason, as we see it, goes to the extent of saying that even where the court permits one side to rely upon judicial notice, yet this does not preclude the opposite party from disputing the fact so noticed if it he disputable.
As said by Justice Swayne in speaking of judicial cognizance in Brown v. Piper, 91 U. S. l. c. 42-43: “This power is to be exercised by courts with caution. Care must be taken that the requisite notoriety exists. Every reasonable doubt upon the subject should be resolved promptly in the negative.”
And in 7 Encyclopedia of Evidence, p. 892, it is said: “It has been said that courts should refuse to exercise the function of judicial notice where there is any reasonable doubt of its propriety.”
In this case, the doubt should have been resolved in favor of defendant and it permitted to have intro-duced this evidence.
*598On this question, 4 Wigmore on Evidence, sec. 2567, says: ‘ ‘ That a matter is judicially noticed means merely that it is taken as true without the offering of evidence by the party who should ordinarily have done so. But the opponent is not prevented from disputing the matter by evidence, if he believes it disputable. It is true that occasionally a court is found declaring a thing judicially noticed and at the same time refusing to listen to evidence to the contrary; but usually this is in truth laying down a new rule of substantive law by declaring certain facts immaterial; whenever a court forbids the production of evidence, it removes the subject from the realm of the law of evidence properly so called.”
The fact that courts in the first place, and as making out a prima-facie case, will take judicial notice of certain things, does not preclude the opposite party from rebutting such prima-facie case, and if the facts judicially noticed are disputable, then the party is not and should not be prevented from disputing them, if in fact he can do so. Judicially noticing facts, like many presumptions entertained by the courts, is but a rule of evidence, and if the question is a disputable one, or can be disputed, evidence so disputing it is competent and should be admitted. This is the rule laid down by Wigmore and other authorities and is well founded in reason. [4 Wigmore on Evidence, sec. 2567 et seq.]
The questions as to the instructions need not be discussed. They were given upon the erroneous theory which pervaded the whole case and can be shaped to accord with these views upon a new trial. The petition, as stated, attempts to state a cause of action under section 8802, but is defective in not charging that the mine in question generated gas. Plaintiff failed to make a case without such proof owing to such erroneous theory. The cause should be and is reversed and remanded that plaintiff may' take such *599further steps as she desires in harmony'with the views herein expressed.
Gantt, Burgess and Fox, JJ., concur; Woodson, J., concurs, hut is of opinion that the defense of duress attempted to be injected in the case by the evidence offered, is no defense to the action, although it had been properly pleaded, and that we should so say at this time. Valliant, G. J., who wrote the principal opinion in division, files his opinion there written, as a dissenting opinion here. In this opinion of V-allicmt, G. J., Lamm, J., concurs in all except that portion wherein it is intimated that the evidence offered on the question of the alleged duress would be proper.