The opinion of the court was delivered by

The plaintiffs in error except to the deposition of David Marten, in whole and in part. He objects that the witness has a direct interest, that he swears about an article, signed by himself and James Williamson, and he also excepts to that part of the deposition in which the deponent says: “ When James Williamson paid the said John Devling the one hundred dollars, the contract with Thomas Williamson was considered at an end by all parties.” It is sufficient to observe, that the first two reasons are destitute of any plausibility. I shall, therefore, confine my remarks to the exception to the part of the deposition which has been noted. After the deposition was read, the counsel excepted to this part, but the court overruled the exception, stating that there was no special exception to these words until after the bill was signed and the deposition read. We are not satisfied with the reasons assigned. It is an undoubted right, of which a party cannot be deprived, that, when he discovers, at any stage of the cause, that improper testimony has been inadvertently received, he may have the error corrected, on application to the court. When the attention of the court is called to it, it is their duty promptly to reject it, and the sooner the minds of the jury are disabused the better; they ought not to be permitted to be influenced by testimony not properly nor legitimately before them. The party injured may have it corrected, either at the time it is discovered, or he may request the court to charge the jury to disregard it. But was this part of the deposition admissible ? We cannot perceive that it is open to the objection, that it is merely the opinion of the witness; on the contrary, we conceive that it is the assertion of his knowledge of the fact, that *317all the parties agreed that the contract was at an end. It was “ considered” viz. it was understood or agreed, that the contract should be cancelled. It is very like the case of Cotton v. Huidekoper, 2 Penn. Rep. 149, and many of the remarks there are applicable here. Some latitude must be allowed in examining depositions, as many of them otherwise, being taken without the aid of counsel, would be inoperative. It does not appear from what source the deponent obtained his knowledge, but had the defendant attended at the taking of the deposition, which it was his duty to do, on the cross-examination or in chief, it might have appeared whether the witness arrived at the conclusions, from the express declaration or agreement of the parties, or. it might have been shown that this was merely his own impression or understanding of the transaction.

The next is the exception to the administration account. Mr Hepburn, who, at the time, was at the bar, testifies that he got the account from the clerk of the orphans’ court of Cumberland county. He says he got the paper out of the files, and that, it is the only paper, on file in that office, relating to the estate of Thomas Williamson. The administrator’s account was admitted to prove item No. 10, touching the payment of one hundred dollars, which was truly supposed, by both parties, to have a material bearing on the issue. To permit a- person, other than the officer to whom is committed the keeping of the records, to take them out of the office 'is a most dangerous and pernicious practice. To save expense, and sometimes to avoid delay and trouble, when a paper has been unexpectedly wanted, this reprehensible practice has obtained in this state. From this it has resulted that many of the records and documents have been lost or mislaid. But this practice should be corrected. And even where the trial is had in the county, the record should (if permitted to be brought into court at all, and this should only be allowed under special circumstances) be entrusted only to the sworn officer or to a person specially authorised by him. The public documents should not be allowed to go into the hands of any person, unless to one answerable for their safe custody. But here the practice has been carried to a much more unwarrantable extent. A paper purporting to be a record, but which has no official mark upon it, is brought to a distant county, by a stranger having nothing to do with its custody, and who has no other knowledge of its authenticity except what arises from the fact, that he himself took the paper from the file in the proper county. Besides the danger that records may be defaced, lost or mislaid, we are exposed to the danger of imposition and fraud. From the high character of the witness, there can be no imputation of any unfair dealing here; but it must be recollected that we are settling a precedent, which may lead to very great abuses in the hands of the artful and unscrupulous. There is nothing lost on the score of convenience in excluding such testimony, as the party may have the benefit of the evidence by a certified or sworn copy of the record, *318or when the original document is required by a subpoena duces tecum to the proper officer, or by a special order of the court. This proof is sometimes necessary to obtain the production of original papers filed in the surveyor general’s office, in the land office, or in the executive department. It would be thought an extreme irregularity to say the least of it, if, on the trial of a cause, public documents belonging to either of these officers should be received as testimony, on the oath of a person not having any official connection with them deposing to the fact that he had taken them off the file; and it would be still more objectionable if it appeared that the papers had no official mark upon them. In all cases, whether the trial be in or out of the county, where the original is required, there should be a subpoena duces tecum, or a special order of the court. Nor should an officer, on any pretence whatever, allow a paper to ,be taken from the office, except in obedience to the process or order of the court. If our public officers were aware of the difficulties to which they or their sureties may be exposed by the mutilation or loss of records, this evil would be promptly corrected. It is very well known that there is hardly a case which involves the investigation of an ancient transaction, but gives rise to embarrassments arising from this cause.

_ Both parties claim under Thomas Williamson. The plaintiffs as his heirs at law, the defendants by virtue of the contract of the 4th February 1833. This contract is not denied, but it is said that it was cancelled, either in the life time of Thomas Williamson or since his death. Nothing appears in the testimony which satisfies me that the contract was annulled in the life time of Thomas Williamson. The letter of the 5th of February is not a rescission of the contract of the previous day, although it suggests difficulties in its completion which put it in the power of Williamson to put an end to the agreement. But instead of pursuing this course, if we are to believe the testimony, both parties considered the contract as subsisting, and entered into subsequent stipulations, by which a sale was to be made, under certain terms and conditions, to Hepburn & Co., in pursuance of a prior agreement. This case will turn, in a great measure, on what occurred after the death of Williamson, and this will mainly depend on the credit to be given to the witnesses: of this the jury are the exclusive judges.

It is insisted that there was error in instructing the jury, “that at all events the verdict should be in favour of the plaintiff.” The court would seem to have been of the opinion, that whether the contract was rescinded or not, inasmuch as the purchase-money was unpaid, the plaintiff was entitled to a verdict, to be released on certain conditions; and that, although the deed may not have been tendered before the commencement of the suit. And in this direction they are supported by Smith v. Webster, 2 Watts 478; although it cannot be disguised, the decision is in opposition to Southerland v. Purry, 3 Penn. Rep. 145; and Brown v. Metz, 5 *319Watts 164. The case of Smith v. Webster puts the point on its true grounds. Where a plaintiff has the legal title it is all that is required to enable him to maintain the action of ejectment. The defendant, who has the equitable title, goes into chancery, who enjoins the plaintiff from proceeding at law, and the defendant becomes the actor. But chancery will in no case enjoin the plaintiff, unless the defendant has done equity, by paying or agreeing to pay the purchase-money. Where, therefore, he has not paid nor offered to pay, nor is willing or ready to perform his agreement, he has no right to a conveyance, and equity will not interfere to protect his possession. A court of chancery always considers the condition of the parties at the time of the decree, rather than their situation at the commencement of the suit. In analogy to this acknowledged power of a court of equity, we have introduced the practice of doing equity by means of a conditional verdict, and in this way the ends of justice are answered, by a verdict in the nature of a special decree. This course possesses this decided advantage, that the whole controversy may be settled in one suit, as it is the duty of the jury, when the defendant defends his possession on the ground of equity, arising from a purchase, to ascertain the amount if any that is due, and to give a verdict for the plaintiffs, to be released on payment of the arrears of the purchase money.

In this state, where a defendant defends on the ground of an outstanding equity, there is no reason that the same principles should not be applied; and as to the costs, it is already decided, in Hart v. Porter’s Executors, 5 Serg. & Rawle 203, since repeatedly recognised, that the jury may, in the verdict, under the direction of the court, do equity.

Judgment reversed, and a venire de novo awarded.