Prior to the passing of the several resolutions hereinafter mentioned, the New York & New England Railroad, a double track railway from Boston to the Hudson river, and the New York, New Haven & Hartford Railroad, another double track railway from Boston by way of Springfield to the city of New York, crossed Asylum street, a much traveled highway in the city of Hartford, side by side and at grade. The situation was further complicated by the fact that each of the railroad companies had one or more side tracks crossing the street parallel to their main tracks and extending a considerable distance each way therefrom, and that the passenger station used in common by the two companies was immediately contiguous to said street. It was a condition of things exceptional and dangerous—dangerous to travel along the street and dangerous to every train on both the railroads, and perhaps most dangerous of all to persons approaching or leaving the station. In the year 1884 the General Assembly, in the exercise of its supreme authority, determined that it was necessary for the public safety that this dangerous condition be changed by separating the grade between the street and the tracks of the railroads, and to that end passed a resolution, approved April 4th, 1884, and which is on page 1026, volume 9 *79of the Special Laws. The sixth section of that resolution was amended by a resolution approved March 3d, 1885, found on page 21 of volume 10 of the Special Laws. In the year 1885 another resolution was passed, and approved March 26th, 1885, found on page 80 of volume 10 Special Laws; and in 1886 still another resolution, approved February 19th, 1886, found on page 212, of volume 10 Special Laws. These are the several resolutions referred to in and made part of the application in the present case.
In reference to these resolutions, and speaking of them all as parts of one act, as in fact they are-, this court in Woodruff v. Catlin, 54 Conn., 295, said:—“The act in scope and purpose concerns the protection of life. Neither in intent nor fact does it increase or diminish the assets either of the city or of the railroad corporations. It is the exercise of the governmental power and duty to secure a safe highway. The legislature having determined that the intersection of two railways with a highway in the city of Hartford at grade is a nuisance dangerous to life, in the absence of action on the part either of the city or of the railroads may compel them severally to become the owner of the right to lay out new highways and new railroads over such land and in such manner as will separate the grade of the railways from that of the street at intersection; and may compel them to use the right for the accomplishment of the desired end; may determine that the expense shall be paid by either corporation alone or in part by both, and may enforce obedience to its judgment. That the legislature of this state has the power to do all this for the specified purpose, and to do it through the instrumentality of a commission, it is now only necessary to state, not to argue.”
To abolish this grade crossing and to insure the safety of the public thereat the legislature invested its commission with very broad powers. It was authorized and empowered to order the carrying of the tracks and the structure therefor over Asylum street, and direct such a change in the grade of the street in its present line and direction as they should judge necessary and proper to the end aforesaid, and *80to order the railroad companies or either of them to lay out, construct and maintain a new line or lines of railroad for a distance not exceeding one half a mile on each side of the street and within three hundred feet of the center line of the present tracks of the railroads, and require any or all the present tracks within these limits to be taken up and removed; to make any and all orders relating to said improvement and to all matters and things appertaining thereto, which they might deem necessary and proper, in the same manner and to the same extent that the General Assembly itself might do and direct. And it was authorized to direct by whom, when, and how, the work should be performed. And that there might be no failure in accomplishing the purpose which the legislature had in view, it was provided how vacancies in the commission should be filled; that the decision or action of the board of commissioners had by a majority thereof should in all matters appertaining to its duties have the full force and authority .and be regarded as I-the decision and action of the board. (And finally it was ¡ authorized to apply to any court of competent jurisdiction ! for aid in any matter appertaining to said work, and to pro-j cure the enforcement and execution of their orders; and the courts of this state and the judges thereof were fully em- ; powered, upon proceedings brought by or at the instance of '■ the commissioners, to enforce by mandamus or otherwise i, the orders of the commissioners made under the authority of !■ said resolutions. \ Even with such a panoply of power the history of the commission appointed by the resolutions shows that it had no easy task. There were divergent counsels to be harmonized, rival if not hostile interests to be placated and so far as possible to be brought into accord, and there were contradictory plans to be considered, re-considered, modified, accepted or rejected.
At an early stage in its labors the commission had it in contemplation to remove the grade crossing by a plan called the “westside ” or the “Bunce” plan, which was to change the tracks of the railroads a few feet westerly from their present line and to carry the street over them upon a bridge, *81and had made orders and commenced proceedings towards carrying out that plan. But' on the 11th day of March, 1887, the commission voted that the vote adopting the “Bunce” or “west side” plan, and all other votes and orders theretofore made and passed in accordance therewith, and confirming, approving, renewing and re-enacting the same, be and the same were rescinded. At the same meeting it was also voted “ that the New York, New Haven & Hartford Railroad Company, and the New York & New England Railroad Company, are hereby ordered to carry their tracks over Asylum street, leaving a clear space ber tween said structure and said street of not less than sixteen feet, in general accordance with the plan and drawings submitted to the commission February 4, 1887, and marked ‘Proposed Station at Hartford, Conn., Feb. 15, 1887 and for this puipose the city of Hartford is hereby directed to lower the grade of said street under said tracks two feet; and in case of disagreement between said parties details of construction to be hereafter determined by this commission.”
The plan and the drawings referred to in this vote do not appear in the record before us. It is very evident however from the prominent reference which it received in the vote that the “ station at Hartford ” was a material if not a controlling feature in the plan thus adopted. To carry the tracks of the railroads over the street so as to leave a clear space of sixteen feet, would require the structure to be commenced from a third to a half mile distant from the street. Such a structure would necessarily have to conform to, or be conformed to by, the station. It is therefore highly probable that the entire plan according to which the two railroads were to carry their tracks over Asylum street was made to depend upon the question of that station. The more so when it is kept in mind that “ depots for passengers and freight are essential parts of the railroads themselves.” State ex rel. N. Haven & Derby R. R. Co. v. R. R. Commissioners, 56 Conn., 313.
All the parties in interest seem to have acquiesced in the order so passed. Work pursuant to the plan so adopted *82commenced at once and proceeded witli reasonable dispatch, so that on the 20th day of December, 1888, “ the bridges and approaches thereto for the purpose of carrying the tracks of the New York, New Haven & Hartford Railroad and the New York & New England Railroad over Asylum street in the city of Hartford, having been nearly completed in general accordance with the plans and orders heretofore made by the,board,” at a meeting of the commission held on that day at which all parties were present and were duly heard, the commission voted as follows :—“And now after consideration the hoard * * * finds that the completion of' the said improvement as heretofore ordered, the carrying out of the designs and instructions of the. legislative acts creating and regulating this board, and public convenience and necessity all require, and this board deems it necessary and proper to order and direct, and we do accordingly order and direct, that the New York & New England Railroad Company and the New York, New Haven & Hartford Railroad Company severally take up and remove their surface tracks between the line of the face of the abutment on the south side of Asylum street and the line of the face of the abutment as now located and established on the north side of Church street, so called, within thirtjr days after the new depot at said Asylum street shall be occupied and used by fsaid companies respectively.”
Of the passing of this vote and order due and proper notice was given to both railroad companies. The New York & New England Railroad Company having failed and refused to comply therewith, the board of commissioners made the present application to the Superior Court for Hartford County for a peremptory mandamus. Upon the coming in of the alternative writ the railroad company appeared and filed a motion that the matter be removed to the next Circuit Court of the United States for the District of Connecticut; which motion was denied. The company then moved that the alternative writ of mandamus be quashed; which motion was overruled. Thereupon the railroad company made its return to the alternative writ as on file; to which return the *83applicants demurred. The Superior Court sustained the demurrer, found the allegations of the application to be true (for the want of any sufficient answer thereto), and ordered a peremptory writ of mandamus to issue. From this order the railroad company now appeals to this court.
There is a somewhat formidable array, in number, of reasons of appeal. It is not necessary to mention them all. It will be much more convenient to group the questions as they have been presented in the progress of the case,—under the motion to remove, under the motion to quash, and under the several paragraphs of the return.
Under the charter of Charles II. the General Assembly of j the colony was the supreme judicial as well as the supreme ¡ law-making power. And notwithstanding the constitution, article fifth, section one, provides that “ the judicial power Í of the state shall be vested in a Supreme Court of Errors, a t Superior Court, and such inferior courts as the General As-j sembly shall from time to time ordain and establish,” the j General Assembly still possesses, in the highest degree that | any legislature in any state can, “ that inherent and plenary j power which enables it to prevent all things hurtful to thej comfort and welfare of society.” It has from time to time, ! and at many times, delegated “ power and jurisdiction ” to | courts and committees for the protection of the lives, limbs, I health, comfort and quiet of persons and the protection of property within the state. Wheeler’s Appeal from Probate, 45 Conn., 306, and the cases cited in the opinion ; Raymond v. Fish, 51 Conn., 80 ; Dunham v. City of New Britain, 55 Conn., 378.
This court decided in the case of Woodruff v. Catlin, supra, that the resolutions now under consideration presented an instance in which the sovereign power of the state directly interfered for the protection of life. Having determined that the grade crossing at Asylum street in Hartford was a menace and a danger to public safety which ought to be removed by separating the grade of the street from that of the tracks of the railroads, and having fixed the. proportion of the expense beyond which, in no event, should the city be *84charged, and having defined the limits within which the commission should have authority, it sent out its commission to perform the work. Itself passed upon and decided the general question. The details and the carrying of them out it delegated in the most explicit language to the judgment of the commission.
Without undertaking to decide whether this proceeding is a “suit of a civil nature at common law or in equity,” or whether an application for a mandamus may be removed from a state court to .which it has been made to an United States court, it will be agreed that there was no error in denying the motion to remove the cause from the state court unless there is in it some question of which the federal courts can take cognizance.
The tenth amendment to the national constitution provides that “the powers not delegated to the United States by the constitution nor prohibited by it to the states, are reserved to the states respectively or to the people.” It may therefore be stated as a general proposition that the police power in the United States is located in the states. The state is entrusted with the duty of enacting and maintaining all the internal regulations which are necessary for the preservation of rights and the prevention of injury to the rights of others. The United States government cannot exercise this power except in cases in which the power of regulation is granted to the general government expressly or by necessary implication.” Teidman on Police Power, sect. 201 ; Cooley’s Const. Limitations, 574 ; United States v. DeWitt, 9 Wall., 41 ; Patterson v. Kentucky, 97 U. S. R., 501. In the case last cited the Supreme Court of the United States said (p. 504 :)—“ By the settled doctrine of this court the police power extends at least to the protection of the lives, the health and the property of the community against the injurious exercise by any citizen of his own rights. State legislation strictly and legitimately for police purposes does not, in the sense of the constitution, necessarily intrench upon any authority which has been confided expressly or by implication to the national govern *85ment. The Kentucky statute under examination manifestly belongs to that class of legislation. It is in the best sense a mere police regulation deemed essential to the protection of the lives and the property of the citizens.” Nor is there anything in the Fourteenth Amendment which varies the doctrine. In Barbier v. Connolly, 113 U. S. R., 27, the Supreme Court again said in reference to that amendment:— “ But neither the amendment—broad and comprehensive as it is, nor any other amendment, was designed to interfere with the power of the states, sometimes termed their police power, to prescribe regulations to promote the health, peace, morals, education and good order of the people.” Civil Rights Cases, 109 U. S. R., 3 ; Ex parte Yarbrough, 110 id., 651 ; Rosenbaum v. Bauer, 120 id., 450 ; Mugler v. Kansas, 123 id., 623. These and many other cases which might be referred to show that no federal jurisdiction can attach to this exercise by the legislature of Connecticut of. its police authority.
Most of the reasons set forth under the motion to quash are repeated in the return and can better be considered there. Of those that are not so repeated one is, “ that the application on which the alternative writ was issued was not verified by an affidavit.” In applications brought for the enforcement of public rights an affidavit is not necessary. High on Ext. Remedies, sect. 507 ; State v. Wilmington Bridge Co., 3 Harr., 312. Another is, “ that the application was not signed by the commissioners, but by their counsel.” As the resolutions of the legislature direct the court to act upon any application brought by, or at the instance of, the commission, we think there was no error in overruling the objection. The objections based on the alleged want of service of the alternative writ were properly disregarded.
We come now to the return. This is demurred to generally and specially, as a whole and as to each of the paragraphs separately; among other reasons, because it joins in one plea matters of traverse, matters of confession and avoidance, and allegations of the legal insufficiency of the appli*86cation. So far as these reasons of demurrer relate to merely formal defects, or other defects that might have been removed by any amendment which did not add to the substance of the allegations in the return, we think they were waived at the hearing below and cannot be considered here.
The alternative writ of mandamus is usually regarded as standing in the place of the complaint in an ordinary action, and it must show a primd facie case entitling the applicant to the extraordinary remedy asked for. In the present case the facts alleged in the alternative writ are the several resolutions of the legislature creating the applicants a board of commissioners and conferring on them certain powers, and the order made by them as such commissioners and the non-compliance with that order by the respondent. These facts did show a clear primd facie case. The return to an alternative writ is demurrable unless it shows a right to refuse obedience to it; and it must state the facts which justify such refusal clearly, specifically, and with such sufficient certainty that the court can see at once that such facts, if admitted or established, do furnish a legal alternative for obedience to the writ. High on Extraordinary Remedies, sections 449-460 ; State ex rel. Cothren v. Lean, 9 Wis., 279 ; Springfield v. County Comrs., 10 Pick., 59 ; Moses on Mandamus, 210 ; Commercial Bank v. Canal Comrs., 10 Wend., 25.
There is in the return before us no direct denial of the facts alleged in the alternative writ; and it is possible that even such a denial, had it been made in this case, would not have withstood the test of a demurrer. It would deny in terms what the court would be bound to know judicially to be true, that is, the existence and the terms of the legislative resolutions; while the order made by the commission and the non-compliance therewith are admitted or are shown by the exhibits made a part of the return itself. We need not discuss this. A general denial puts in issue the existence of those facts which, if they exist, constitute a primd facie cause of action or ground of defense. When these facts exist, but by reason of some extraneous features or elements affecting them they do not produce the otherwise *87necessary result, that element which destroys the primd facie legal effect of the facts is not put in issue by such a denial. It is new matter and must be specially pleaded. And so where a legal right to refuse obedience to a writ can be shown in no other way than by setting forth such extraneous features or elements, a return that omits them is clearly bad on demurrer.
The first paragraph alleges as a reason why the peremptory writ should not issue, that Morgan G. Bulkeley, one of the commissioners, was a citizen and a tax-payer of Hartford, and as such was interested in the result, and that by the resolutions he was made a judge in his own cause. The second paragraph alleges in substance the same reason against Henry C. Robinson, and the eighth paragraph a similar reason against Nathaniel Wheeler. It seems to us that the commissioners are in no just sense parties to this proceeding. True, it is entitled with their names, but it is so only by a mistaken use of terms. In this cause the state is itself proceeding as directly as it does in a criminal prosecution. The state is the party. It would never be thought proper that a criminal case should be entitled in the name of the state’s attorney against the person prosecuted. He is the mere agent which the state employs to carry on its own prosecution. That might be an allowable figure of speech Avliich should put the mere instrument used in the doing of an act for the actor himself. But as the statement of a fact it could never be allowed. The surgeon’s knife with which he removes the gangrene from the body of his patient can never be made to mean the same thing as the hand that Avields it. Not being parties, it follows that it is not their cause.
And there is nothing in the objection that the commissioners were judges, and were interested in the matter to be decided. They were appointed to carry out the decree of the legislature that the nuisance of the grade crossing should be removed; and they had substantially no power except to exercise a choice as to the means by which the decree should be enforced. It is true that the commission was to deter*88mine upon what should be allowed as the entire expense of the improvement, and as to how this sum should be apportioned between the two railroads and between the railroads and the city. Their action in this matter may perhaps be regarded as quasi judicial. This however is not the exact objection made, but that two of the commissioners represented respectively the city and the railroads, and that each of these commissioners was interested in this apportionment, the representative of the city having an interest as a citizen and tax-payer in making the share set to the city as low as possible, and the representative of the railroads having an interest as a stockholder in making as small as possible the sum assigned to the railroads. But the legislature deemed it best to constitute the commission by taking as its basis the three railroad commissioners, whose freedom from personal interest or bias is not questioned, and adding to them two other members, one as representing the city and interested in its behalf, and-the other as representing the railroads and interested in their behalf. The purpose of the legislature in the matter is made entirely clear by the provision of the resolution that if the member representing the city should decline to act the common council of the city should appoint a person to take his place, and if the member representing the railroads should decline to act that the railroad companies should appoint a person to take his place, this appointment requiring the concurrence of the two companies, so that he became the representative of both. The advantage of this arrangement was that the interests of each party would be thoroughly looked out for, while the interest of one of the members was balanced by that of the other, and the remaining members were a majority and could determine any matter by their vote. We know of no reason why such action on the part of the legislature is not valid. It had power to constitute the commission as it chose, while its action in this respect was perfectly fair to'wards all the parties. Whatever objection could have lain against Mr. Robinson as interested in one of the roads more than in the other and as interested in favor of the city of Hartford as a tax-payer *89of the city, was removed by his declining to act and the appointment by the two companies of Mr. Wheeler, who was not a tax-payer of the city and had no interest in its favor.
In the defendant’s brief it is contended that the order made by the commission, and recited in the alternative writ, was passed when the commission was functus officio. The third, fourth, fifth, sixth, seventh and ninth paragraphs of the return are all dependent upon this contention. An officer, a commission, a board, or a committee, is functus officio when it has performed its duty. The commission created by the legislative resolutions was functus officio if it liad completed the work it was set to do.' That work was to so change the condition of things at the crossing in Asylum street as to make it safe, so far as possible, for everybody ; safe for people on the railroads, safe for travellers along the street, and safe for those going to or coming from the depot. Deciding upon a plan according to which the work might be done did not do the work. Many plans might be agreed upon, changed or rejected, and new ones adopted, without advancing the work itself at all. The duty of the commission included not only such service as is done by the architect who designs the plan of a house, but also the work of the builder by whom the edifice is constructed; and the latter work is not completed until the rubbish is cleared away from the finished structure and it is made read}r for habitation. This commission could not be functus officio so long as anything remained to be done to remove the danger at that crossing.
Paragraphs ten, eleven and thirteen were apparently intended to be denials of the averments, or some of them, in the alternative writ. But as denials they are insufficient. Neither of them denies any fact directly. The tenth, for instance, denies not the fact of the resolutions but their purpose, which can be made out only by argument. So too the eleventh. An argumentative denial is no denial. Viewed in this way the demurrer to these paragraphs was properly sustained. We do not, however, rest our decision on this ground alone. “ If any pleading mistakes the effect and *90purpose of a statute upon which a party relies, the adverse party, in demurring to such pleading, does not admit the correctness of the construction, or that the statute imposes the obligation or confers the rights which the party alleges.” Pennie v. Reis, 132 U. S. R., 470. “ A demurrer does not admit the accuracy of an alleged construction of an instrument, when the instrument itself is set forth in the pleading or a copy annexed, against the construction required by its terms ; nor the correctness of the ascription of a purpose to the party when not justified by the language used.” Dillon v. Barnard, 21 Wall., 437. The eleventh paragraph is somewhat more full in its statement than the tenth. It says that at the time when the order of the commission took effect— namely, thirty days after the new depot was occupied by the railroads—the said New York & New England Railroad Company “ did not have any such surface tracks anywhere within the iimits named in said order as could in any event have anything to do with the intent and purpose of the said resolutions of the General Assembly, under the plans adopted either by said board of commissioners or by the plaintiffs assuming to act as such.” A demurrer to such pleading does no more than refer to the court the construction of the legislative resolutions.
It appears from other parts of the record that before the expiration of the thirty days named in the order the defendant had removed its surface tracks from the south side to the north side of Asylum street, and that such remaining part of its surface tracks as is within the limits fixed by the'order it had at all times refused to remove. It is to secure the removal of this remaining portion of surface tracks that the mandamus is asked for in this application. The defendant insists that the legislative intent and purpose authorized the commission to direct the removal of surface tracks only between the lines of Asylum street. The general question argued under these paragraphs is whether or not the commission exceeded the powers conferred upon it by the legislature in making the order, so far forth as it relates to that portion of the defendant's tracks not removed. A compari*91son of the order -with the resolutions shows—and it is admitted—that the tracks to which the order relates are within the territorial limits over which authority is given to the commission. It also appears—and is not denied—that it is within the terms of the power given to the commission, that is, “ to make any and all orders relating to said improvement and to all matters and things appertaining thereto which they may deem necessary and proper, in the same manner and to the same extent that the General Assembly itself might do and direct.” The legislature by the use of this language evidently considered it essential to the fulfilment of its entire scheme that the power of its commission should be as paramount anywhere outside the bounds of Asylum street, if within a half mile on either side, as between the lines of that street. In the 54 Conn., at page 295, cited above, it is said that “ the legislative act in scope and purpose concerns the protection of life ; ” “ that it was an exercise of the governmental power and duty to secure a safe highway.” Whatever then would remove danger would promote that purpose. A surface track anywhere near a passenger depot over which cars at any time might be moving would be dangerous. The removal of such tracks would tend to promote safety. And we have seen that a safe highway at the Asylum street crossing required a safe approach to the depot from the street and a safe egress to the street from the depot. Examining the resolutions in the light of the decision of this court we think the order made by the commission was within the legislative purpose. These considerations show, primá facie at least, that the order was within the power and jurisdiction of the commission.
But the commission established its own jurisdiction. Their record is that “ this board finds that the completion of said improvement as hereinbefore ordered, the carrying out of the designs and instructions of the legislative acts creating and regulating this board, and public convenience and necessity, all require, and this board deems it necessary and proper to order and decree,” etc., etc.; and accordingly it did order and direct the surface tracks to be taken up, as is set *92forth in the alternative writ, the controlling jurisdictional fact being that the commission did deem it “ necessary and proper ” to make the order. It is true that jurisdictional facts found by any board or other tribunal exercising only a limited statutory authority are open to be questioned in any other court. But such a finding is always taken to be true unless shown to be untrue. If the jurisdictional facts so found are made to appear primd facie to be true, they are always held to be true until some extrinsic facts and circumstances which destroy such primd facie appearance are alleged and proved. No such facts are shown in this return.
The thirteenth paragraph, so far as it denies the authority of the commission to make the order of December 20th, 1888, and so far as it denies any allegation in the alternative writ, has been sufficiently considered. Another part of this paragraph “denies that the plaintiffs were legally constituted as a board' of commissioners authorized to act as such under said resolutions of the General Assembly.” This is a denial of a legal conclusion. It denies that the plaintiffs were legally constituted as a board of commissioners. The assertion or the denial of a legal_concl usion, without showing the facts which establish .or destroy such conclusion, means nothing.' A demurrer to such a pleading must always be sustained. We might stop here. It is open to conjecture that the defendant intended to say that because Mr. Wheeler acted as one of the commission in passing the order when he was not one of the persons named in the resolutions as a member of the commission, therefore the commission was not legally constituted. But the resolutions provide that in case Mr. Robinson should refuse to act a substitute may be chosen, and provide in what way. The record discloses that Mr. Robinson did refuse to act as a member of the commission, for he appeared in another capacity. It also appears from the record that Mr. Wheeler acted as one of the commission with the acquiescence of the other members. We think the court was authorized to presume that he acted legally. Even if the court was wrong in so presuming, the order was not thereby made invalid, for the resolutions further provide *93that the decision or action of the board of commissioners had by a majority thereof should in all matters appertaining to its duties have the full force and authority of, and be regarded as, the decision and action of the board.
What we have said under the motion to remove the cause to the Circuit Court of the United States fully answers the fourteenth paragraph of the return. There is nothing in the legislative resolutions in violation pf the constitution of the United States. The demurrer to the fifteenth, sixteenth and seventeenth paragraphs was properly sustained upon the authority of Woodruff v. Catlin, supra. The demurrer to the eighteenth paragraph is sustained on the ground that forbidding the defendants to use their property in a way that would be dangerous to the lives of others is not a taking for public use. The prohibition of the use of property in a particular way, whereby its value becomes depreciated, is a very different thing from taking it for public use. To the nineteenth, because the legislature itself decreed the apportionment of the expenses. What we have said under the first paragraph of the return is a sufficient disposition of paragraphs twenty and twenty-two. Paragraph twenty-one is answered by Woodruff v. Catlin, supra. And see Mugler v. Kansas, 123 U. S. R., 623. The twelfth paragraph alleges only that the defendant would be subjected to great expense if the order of the commission should be carried out. The resolutions and the order being valid, and being required for the protection of life, the circumstance that its enforcement would subject the defendant to expense is not any reason against its legality. That is an argument to be addressed to the commission. So far as we have been able to examine we find no reason why the commission might not take any special damage to the defendant, or to the city of Hartford, or to the New York, New Haven & Hartford Railroad Company, into account as a part of the “entire expense,” and determine what proportion each should bear, subject only to the limitation fixed in the resolutions.
There is no error in the judgment appealed from.
*94In this opinion Loomis and Thayer, Js., concurred.