delivered the opinion of the court.
The first of the above-styled cases is here on appeal from a judgment of the circuit court of Hinds county, the case having been tried there on certiorari to the State Railroad Commission as assessors of railroads. The purpose of the writ was to bring before the court the record and proceedings of the commission in back-tax assessing and classifying the Gulf & Ship Island Railroad Company for each of the five years from March 1, 1898, to March 1, 1903, and to have judicially ascertained whether the commission had not transcended its powers in back-tax assessing and classifying the said railroad, and classifying it as a road claiming exemption from state supervision under maximum and minimum provisions in its charter, and assessing and classifying it for the payment of the privilege tax of $10 per mile for each of the years named, in addition to the privilege tax paid by it during each of said years as a railroad of the third class. The circuit court affirmed the judgment of the commission, and ordered a writ of procedendo to be issued.
The second of the said cases is here on appeal from the chancery court of Hinds county. It was heard and decided on demurrer interposed by the Yazoo & Mississippi Valley Railroad Company, appellant here and defendant below, to a bill filed by Wirt Adams, state revenue agent, in which complainant set *794up the order of the railroad commission of July 18, 1904, which found that the said railroad company had escaped taxation on its railroad for an additional privilege tax of $10 per mile for each of the years from March 1, 1898, to March 1, 1903, by reason of not having been assessed and classified as a railroad claiming exemption from state supervision under maximum and minimum provisions of its charter, and ordered and adjudged that the objections of said railroad company be overruled; that the classification of said railroad under sec. 66, ch. 5, p. 23, Acts 1898, into first, second, and third classes, according to its parts, made during each of said years (the privilege tax for such first, second, and third classes for such years having been paid), be confirmed; and that said railroad company and railroad be back assessed and classified, as a railroad claiming exemption from state supervision under maximum and minimum provisions in the charter for the said years, for the payment of the additional privilege tax of $10 per mile for each of said years on each mile of its railroad in the state. The bill prayed for a decree for $42,187.40 against said railroad company, with interest; that a lien be decreed for same against the property of said company; and, if said sum should not be promptly paid, that the property of the said company be sold to pay the amount so decreed to be due for said unpaid privilege taxes. The demurrer was overruled and decree entered, for appellee.
In the consideration of the first case we are confronted in limine with the contention that the court upon certiorari cannot review the finding of fact by the commission, because the statute creating the remedy by certiorari (Code 1892, § § 89, 90) declares that the court shall be confined to the examination of questions of law arising or appearing on the face of the record and jn’oceedings, and because the statute gives the commission no authority to sign a bill of exceptions, and, in fact, no bill of exceptions was taken. The reasons assigned may be conceded, but the conclusion does not follow. Certiorari is *795the great corrective writ by which the superior courts exercise a supervisory power over inferior courts, tribunals, and boards which exercise judicial functions, and by which their records and proceedings are brought under review, to the end that all abuses of power may be corrected and that they may he held strictly to the jurisdiction marked out for them and prevented from transcending the powers by law conferred upon them. 4 Eney. PL & Pr., 10. The state railroad commission is an inferior tribunal within the contemplation of sec. 90 of the code, and is subject.to the supervision and control of the superior courts of the state through the writ of certiorari. Railroad v. Adams, 77 Miss., 777 (25 South. Rep., 355).
A mere mistake of fact by the commission will not be corrected by certiorari; but a mistaken finding of fact induced by an error of law apparent upon the record, the finding of a fact contrary to law, or the making of an order beyond the cognizance and power of the commission, can and will be corrected by the superior courts, in the exercise of their supervisory and corrective power, through the writ of certiorm’i. It is the peculiar province of the writ of certiorari to correct errors of law apparent upon admitted or established facts. 4 Ency. Pl. & Pr., 11. It has been held by this court that evidence may be heard in the circuit court in order to make manifest error of law committed by the inferior tribunal. Robinson v. Mhoon, 68 Miss., 712 (9 South. Rep., 887).
The remaining questions passed upon in this opinion, and upon which the decision turns, are common to both cases. They will therefore be considered and decided together. It is contended by appellants that the railroad commission was without. power or authority to back classify these railroads under sec. 66, ch. 5, p. 23, Acts 1898, and classify them as railroads of the third class, and of the first, second, and third classes, respectively, claiming exemption from state supervision under maximum and minimum provisions in their charters. That without such classification the appellants were not liable for the *796additional privilege tax of .$10 per mile was expressly adjudicated by this court in Gulf & Ship Island Railroad Co. v. Adams, and Yazoo & Mississippi Valley Railroad Company v. Adams, 83 Miss., 306 (36 South. Rep., 144). It was also determined in those cases that the said railroads had not been classified as railroads of the first, second, and third class or narrow gauge, claiming exemption from supervision, and that because of the want of such classification they were not liable for the additional privilege tax of $10 per mile as railroads claiming exemption from supervision. The railroad commission, upon demand of the revenue agent, having, since the above decision was rendered, reclassified the said railroads and classified them as railroads of the third class, and of the first, second, and third classes, respectively, claiming exemption from state supervision, it becomes highly important to determine whether the railroad commission, having once classified said railroads under sec. 66, ch. 5, p. 23, Acts 1898, for the years for which the additional privilege tax is sought to be collected, could afterwards reclassify them for the said years and assign them to different classes than the ones to which they had previously been assigned. If the commission had authority to back-classify these railroads at all, the power must be found in some statute. If not found in sec. 66, ch. 5, p. 23, Acts 1898, or in ch. 34, p>: 29, Acts 1894, which prescribe the duties and powers of the state revenue agent, it did not exist, as these are the only statutes from which the power could by any possibility be inferred. Section 66, ch. 5, p. 23, Acts 1898, is prospective, and prospective only. It provides that “the railroad commission shall annually, on or before the first Monday in August, classify the several railroads according to such charter exemption claims and the gross earnings of each,”, etc. The power therein given must be exercised annually on or before the first Monday in August. If not exercised by that date of any year, the power given by that section for that year must fail by the very terms of the statute.
*797It is contended for appellee, in a most ingenious and forceful argument, that all the power needed to enable the commission to make the back classification is to be inferred from the powers conferred upon the state revenue agent by ch. 34, p. 29, Acts 1894. It may be conceded that, if this statute empowers the state revenue agent to have railroads back classified for purpose of privilege taxation, it also empowers the railroad commission to make the back classification. Railroad Company v. Adams, 73 Miss., 661 (19 South. Rep., 91).
It therefore becomes necessary to analyze and construe ch. 34, p. 29, Acts 1894, in order to determine whether the power contended for is thereby given, either in express terms or by necessary implication. If given by this act at all, it must be found in either sec. 2, sec. 3, or sec. 4. It cannot be found in sec. 2. The purpose and entire scope of this section is to arm the revenue agent with power to sue for all moneys due the state, or any county, municipality, or levee board, for any cause whatever, and especially for all past due and unpaid taxes whatever. The right of the revenue agent to sue is not the thing controverted here, but the right of the railroad commission to do an act which is an indispensable prerequisite to a suit by him.. The latter is not to be inferred from the mere giving in general terms to the revenue agent of the right to sue for all past due and unpaid taxes. The power to back classify railroads for privilege taxes is clearly not to be inferred from sec. 3 of the act, for that applies only to back assessments by the tax collector and the boards of supervisors of the several counties. If the power exists at all, it must be found in sec. 4, p. 30, which reads as follows: “If the property which the revenue agent discovers to have escaped taxation shall belong to any railroad or other corporation which, under -the law, is required to be assessed by the state railroad assessors, the revenue agent shall give the notice required herein to said railroad assessors, and they shall give the required notice to the company or corporation. At their next meeting, after giving *798the proper notice, said property shall be assessed in the same manner required by law and placed on the proper county, municipal, or levee board roll, and collected by the proper officers in the manner required by law, and the revenue agent shall have his compensation as in other cases.” On its face this section applies to back assessment of property for ad valorem taxation, and cannot, unless it be by inference, be held to apply to back classification for imposition of privilege taxes.
It is contended for appellee that it is the evident purpose of the statute to make the powers of the railroad assessors for back assessment as extensive as the powers for back assessment conferred on the collectors and board of supervisors by sec. 3, and that the use of the words, “should the revenue agent discover that any person, corporation, property, business, occupation, or calling has escaped taxation by reason of not being assessed, it shall be his duty to give notice,” etc., indicates that the power is given to the tax collector and board of supervisors to back assess or back classify for privilege taxes. We cannot adopt this construction. It is evident, notwithstanding the general terms employed — “person, corporation, property, business, occupation, or calling” — that this section has reference solely to ad valorem taxes on property. Certain of the terms employed are mere redundancies of expression, and are to be restricted by the manifest purpose of the section. The section cannot embrace ordinary privilege taxes, because they do not need to be assessed, and never are assessed, and because the work of classification for privilege taxes, except in the case of railroads, is always done by the legislature, and is never committed to the tax collector or board of supervisors. Back classification for ordinary privilege taxes is not necessary to enable the revenue agent to collect past due privilege taxes, for the reason that the right and authority of the revenue agent to sue for them is perfect without it. The use of the words “assessment,” “property,” “real estate,” “personalty,” negatives the idea that back classification for privilege taxes is contemplated in sec. 4. We *799construe sec. 4 to mean what it appears on its face to mean.. We restrict it to back assessment of property for ad valorem taxation, and hold that it gives no warrant for back classification of railroads in order to an imposition of privilege taxes for past years.
Appellee undertakes to escape the force of this reasoning by contending that the franchise here sought to be taxed is property; that a privilege tax is ultimately a tax upon the use of the property, and is, in effect, a tax upon the property. We do not concur in this, but hold that the tax sought to be collected is a privilege tax proper. But if appellee’s contention in this regard were correct, and the tax sought to be collected were indeed essentially a property tax, still the commission would be estopped now to back assess this franchise for a property tax. It is a matter of which this court will take judicial notice that these railroads were assessed for ad valorem taxation, for the years 1898 to 1903, agreeably to provisions of Code 1892, § 3877, and that they have paid the taxes assessed against them. It was by the statute made the duty of the railroad assessors, in fixing the assessments of the said railroads, to take into consideration the value of the franchise; and by the franchise, in this connection, we understand the right of the railroad companies to operate their railroads in the manner, on the conditions, and with the powers prescribed and granted in their several charters. They are conclusively presumed to have taken the value of the franchise into consideration in fixing the assessment of these railroads for the years in question, and this cannot now be questioned in any tribunal. It is res adjudicaba. It has been expressly adjudicated by this court that, as to all other matters (than exemptions) in the assessment and valuation of the property of railroads, the judgment of the railroad assessor is conclusive. Railroad Company v. Adams, 81 Miss., 105 (32 South. Rep., 937). See also, specially, Railroad Company v. Adams, 77 Miss., at p. 778 (25 South. Rep., 355), and note authorities there quoted.
*800But, of course, this doctrine is not to he extended to assessments procured to be made by fraud nor to assessments made in conscious and deliberate defiance of law. As to all such, whether the property withheld from or escaping assessment be franchise or other property, we adhere to and reaffirm the wholesome doctrine announced in Revenue Agent v. Clarke, 80 Miss., 134 (31 South. Rep., 216).
The franchise of these railroads having been assessed for ad valorem taxation (and for this, in the absence of fraud and the like, as indicated, we have a conclusive presumption of law), it is not now in the power of the railroad assessors to single out some constituent element of their franchise, or some mere incident thereto, and impose an ad valorem or property fax upon it. This would be double taxation and violative of the constitutional provision that taxation shall be equal and uniform. It would also, as has been suggested, violate the constitutional mandate that property shall be taxed according to its value, in this — to wit, that a property tax upon railroad franchises at the rate of $10 per mile, without regard to varying conditions, the volume of business, the earning capacity, or the value of the- several roads upon which it is levied, would be a purely arbitrary tax, not equal and uniform and not according to value.
If the back tax now sought to be collected of the railroad companies which are appellants in the cases now being considered can be upheld at all, it must be upon the ground that they are privilege taxes in the ordinary acceptation of the term. We have already reached the conclusion that they cannot be allowed and collected, because no provision has been made by the legislature for the back classification of railroads with a view to the imposition and collection of privilege taxes for past years. But there is another insuperable objection to the back classification of the railroads and the collection of the additional privilege tax of $10 per mile for the years in question. The power conferred upon the railroad commission by sec. 66, oh. *8015, p. 23, Acts 1898, to classify these railroads for privilege taxes, was exercised for each of the years from March 1, 1898, to March 1, 1903. It wras the duty of the commission to classify them according to charter exemptions (from state supervision) and gross earnings. The commission classified them as railroads of the third class, and of the first, second, and third classes, respectively, saying nothing as to charter exemptions. This classification, in each case, was a judicial act. Everything was concluded by it which was comprehended or involved in it. It amounted to an adjudication that these roads were not liable for the years in question to the privilege tax of $10 per mile as railroads claiming exemption from state supervision. This judgment is final and conclusive, and cannot now be brought in question. Railroad Company v. Adams, 77 Miss., 778 (25 South. Rep., 355); Railroad Company v. Adams, 81 Miss., 105 (32 South. Rep., 937).
It is not necessary to the determination of these cases that we should pass upon the questions raised,' and argued upon each side with such wealth of learning and cogency of reasoning, as to the application to these cases of the constitutional principles that the state shall not pass any law impairing the obligation of contracts nor deny to any person within its jurisdiction the equal protection of the laws.
Reversed, and judgment here in each case for appellant.
Whitfield, C. J., concurs in the result.Judge Calhoon, owing to illness, was off the bench when this case was argued, submitted, and decided. W. M. Cox, Esq., a member of the supreme court bar, was duly appointed, and presided not only in this case, but generally in the absence of Judge Calhoon.