Opinion by
Orlady, J.,Under proceedings instituted by the borough, the plaintiff recovered a verdict of $1,000, as damages sustained in changing the grade of Dickson street. On the trial below it was urged in defense to the claim for damages, that the grade had been established by an ordinance at a time prior to the erection of the buildings on the lots of the plaintiff, and in support of this contention, the borough clerk was called by the defendant and produced the ordinance book of the borough. The ordinance of January 19, 1891, on which the defendant relied was offered in evidence, and to this the plaintiff objected. “I object to the offer of this ordinance, because it is an ordinance establishing the grade of second, third, fourth and fifth avenues extension city farm line, and Dixon street extension and Plummer street; it is not an ordinance fixing the grade of Dixon street. I object further, because it includes the proceedings of eight streets in one ordinance; and further, that the offer does not include the proof of publication by hand bill and in newspapers as required by law.” The objection was sustained, (1st assignment) but as the ordinance is not on the record sent to this court we only dispose of that part of the assignment which suggests the necessity of proof of publication of the ordinance, by handbills and in the newspapers, before receiving it in evidence.
By the Act of April 3, 1851, P. L. 320, sec. 3, par. IV., it is made a corporate duty “ to publish in at least one newspaper if such be printed in the proper county, and by not less than twelve advertisements to be put up in the most public places in *548the borough, every enactment, regulation, ordinance or other general law at least ten days before the same shall take effect and by the preceding paragraph “ to make full records of their proceedings and to provide for the preservation thereof.”
By the eighth section of the act the secretary is required “ to attend all the meetings of the corporation, keep full minutes of their proceedings, transcribe the by-laws, rules, regulations and ordinances adopted into a book kept for the purpose ; and when signed by the presiding officer shall attest the same, preserve the records and documents of the corporation .... record the publication of all enactments and attest the same by his signature thereto.” The offer as made, was unaccompanied by proof of publication, and though the ordinance was not operative until the terms of the act of assembly had been complied with, the only question raised by this assignment is, can the ordinance be received in evidence without the fact of publication being first affirmatively shown ?
By the Act of April 15, 1834, P. L. 537, it is made the duty of the town clerk “ to provide a suitable book or books, for the purpose of entering therein all matters of which he shall by law be required to keep a record ” and by section 9 of the act of 1851 these duties devolve upon the secretary of the borough council. When ordinances are required to be published before they go into effect, this requirement is essential, and the publication must be in the designated mode: Dillon on Mun. Corp. sec. 331.
The posting by advertisements and publications in a newspaper are as essential to the validity of an ordinance as are the other statutory requisites: Sower v. Phila., 35 Pa. 231; Kepner v. Com., 40 Pa. 124; Marshall v. Mayor, 59 Pa. 455; Fuller v. Scranton, 2 Cent. Repr. 788.
The ordinance book is required to be kept, by the express direction of the statute, and the memorial made in compliance with the statute is a public record, and when the proper person presents the proper record in which the ordinance is identified and attested, it is prima facie correct and entitled to be read in evidence: Wharton on Evidence, sec. 644; Thompson v. Chase, 2 Grant Cases, 367.
The records of a school board though not required by law to be kept are admissible, and when defective are explainable by parol evidence : Gearhart v. Dixon, 1 Pa. 224.
*549It was not necessary to prove the preliminary steps taken in passing and publishing the ordinance, as it is well held that the ordinance book is prima facie evidence of the validity of the ordinance, and if anything essential to its validity has been omitted in passing or publishing it, it devolves upon the party resisting it to show such invalidity: Prell v. McDonald, 7 Kan. 426, s. c. 12 Am. Reps. 423; City of Atchison v. King, 9 Kan. 550.
To hold otherwise, would make it necessary to prove that the advertisements were of the statutory number, or that the posting places were the most public in the borough; but while admissible as an ordinance, it is subject to attack, and proof may be adduced to show that it was not legally published and posted, and hence was inoperative.
The first assignment of error is sustained. The second and third assignments are not considered, as they are in direct violation of Rule 17 of this court; the answer of the witness not being given, we repeat what was said in Commonwealth v. Smith, 2 Pa. Superior Ct., 474, “ The reasons for this rule and the importance of it are so clearly shown in Battles v. Sliney, 126 Pa. 460, that we need only to refer to that case.” The fourth and fifth assignments are considered together. A witness, John G. Hastings, a contractor, when questioned as to the amount of damages to which the plaintiff was entitled, testified as follows : “ Q. Do you know anything at all about the value of this real estate in Homestead ? A. No, sir. Q. And the only thing you do know is by observing on this street since the grading was done how much it was cut down ? A. In regard to the house, I went up for that purpose.”
From his evidence, it appears that he had no knowledge of the condition of the property before the grade of the street was changed, nor did he have any knowledge of the value of real estate in the borough; but as a contractor, he simply visited the premises after the changes had been made and estimated the cost necessary to lower the house and make it conform to the new grade. He was not called as an expert, and if his testimony had been confined to the facts of which he had knowledge, it would have been competent, but he knew nothing of the conditions existing before the grade was changed, and could not testify as to the damage resulting from a change of which he admitted he did not have any knowledge.
*550The testimony was received under authority of Dawson v. Pittsburgh, 159 Pa. 317, but we do not think the evidence competent under that case.
Experience has constantly demonstrated the correctness of the old rule established in the case of Schuylkill Nav. Co. v. Thoburn, 7 S. & R. 411, to wit, the jury are to consider the matter just as if they were called on to value the injury at the moment when compensation could be first demanded; they are to value the property, without reference to the person of the owner, or the actual state of his business, and in doing that, the only safe rule is to inquire: What would the property, unaffected by the obstruction, have sold for at the time the injury was committed ? What would it have sold for as affected by the injury? The difference is “the true measure of compensation” is the language of the Supreme Court in Chambers v. South Chester Borough, 140 Pa. 510, and in determining the duty of the jury. The same case is as definite authority for the measure of proof and qualification of a witness, in the following concise direction: “ More and more closely, in recent years, we have held parties to the rule that, after all things are considered which may affect the mind of the witness he must give his estimate of the money value of the injury, by contrasting the market value of the property, as it was before the injury was inflicted, with its value immediately after the injury; and the jury is instructed that the difference of these values is the measure of damage.”
This plain and just rule is the result of many preceding cases noted in that decision, and it has been followed without modification. In P. V. & C. Ry. Co. v. Vance, 115 Pa. 325, it is said: “ In order, therefore, that a witness may be competent to testify intelligently as to the market value of land, he should have some special opportunity for observation; he should, in a general way, and to a reasonable extent, have in his mind the data from which a proper estimate of value ought to be made; if interrogated, he should be able to disclose sufficient actual knowledge of the subject to indicate that he is in a condition to know what he proposes to state, and to enable the jury to judge of the probable proximate accuracy of his conclusions; ” which test of competency is held to be vital in Michael v. Crescent Pipe Line Co., 159 Pa. 99. He cannot intelligently tes*551tify without such knowledge ; its possession is a necessary element in the value of such testimony, but cannot be assumed; the court cannot pass on the question of competency until it is made to appear. Hence the possession and sufficiency of such knowledge should be made to appear and be passed upon by the court before the witness should be permitted to express any opinion. The basic requirements are personal knowledge of the property and of its value at the time it is taken: Orr v. Gas Co., 2 Pa. Superior Ct. 401. While these rules have been varied in instances of limited or special knowledge of particular, property, the Supreme Court has held that it is. safest rigidly to adhere to the principles announced in the cases cited, this being the only fair and safe way to ascertain the actual damage sustained.
The witness, Hastings, did not pretend to have any knowledge of the property; any idea of its market value; the uses to. which it was put; its extent or character; its surroundings or advantages before the change was made; and he could not aid the jury in the least by his estimate of the damages the plaintiff sustained, by giving his opinion “ of the difference between the market value before and after the grade.”
A stranger from a distant state, who saw the property, for the first time on the day of trial, could testify to the same facts. A verdict to be respected must have a firmer foundation.
The fact that sufficient competent testimony was admitted on the trial to sustain-the verdict, is no antidote for the error of admitting incompetent testimony, since an appellate court cannot determine either the effect given by the jury to that which should not have been before them, or whether the verdict was not due wholly to the incompetent testimony. •
The first, fourth and fifth assignments of error are sustained, the judgment is reversed, and a venire facias de novo awarded.