Burke, J.,

delivered the opinion of the Court.

On the 9th of May, 1903, Henry S. Regester and Samuel W. Regester entered into a contract under seal in which the obligations of the respective parties thereto were expressed as follows: • That the said party of the first part (Henry S. Regester) does hereby bargain and sell unto the said party of the second part (Samuel W. Regester), and the latter does herewith purchase from the former two hundred shares of the capital stock of the J. Regester Sons Co., now standing on the books of the said company in the name of the said party of the first part, at and for the sum of ten thousand ($10,000) dollars, the same being at the rate of fifty ($50) dollars per share, of which sum five dollars have been paid prior to the signing hereof, and the balance is to be paid in cash at any time within thirty days from above date, updn the delivery of said stock of said company to the party of the second part.

Upon the expiration of the period limited in the contract for the payment of the purchase price of the stock, the vendee was unable and failed to make payment, but subsequently, on the 22nd of June, 1903, he paid on account of the purchase the sum of five hundred dollars, and the time within which he might pay the balance was extended for a further period of thirty days. After this new period of extension had expired, and Samuel W. Regester having failed and neglected to pay for the stock, the vendor, Henry S. Regester, advertised and sold the stock by public auction at the salesroom of Pattison & Gahan, auctioneers, in the city of Baltimore. The stock was bought at the sale for the J. Regester Sons Company by William C. Smith its secretary for the sum of nineteen hundred dollars. The expenses attending the making of the sale were one hundred and ninety-one dollars and sixty cents, and the total net proceeds derived from the sale were eighteen hundred and eight dollars and forty cents. Samuel W. Regester having paid on account five hundred and five *9 dollars, the difference between the contract price and the net amount realized from the sale of the stock was seven thousand six hundred and eighty-six dollars and sixty cents, for which sum the vendor sued the vendee in the Court of Common Pleas, and recovered a judgment for the full amount. The appeal in this case was taken from that judgment.

The record contains twenty-seven bills of exceptions— twenty-six of which present questions as to the admissibility of evidence, and the twenty-seventh was taken to the ruling of the Court upon the prayers. The declaration contains three counts, but the case was tried upon the third count— the first and second counts having been excluded from the consideration of the jury by the granted fourth prayer of the defendant. A demurrer, which was overruled, was filed to the third count. This demurrer was not discussed in the brief, or argument of the appellant’s counsel, and as we see no valid grounds of objection to the count, the demurrer will not be further alluded to.

In order to pass intelligently upon the numerous exceptions, it will be necessary first to understand the precise issues raised upon the pleadings; secondly, the rights and obligations of the respective parties under the contract; thirdly, the evidence introduced, and fourthly, the nature and character of the testimony which was offered by the appellant and which the Court refused to admit—the exclusion of which constitutes the ground of twenty-six exceptions, and to determine whether there was reversible error in the refusal of the Court to admit the proffered testimony.

The third count is based upon the writing obligatory executed by the parties on the 9th day of May, 1903. It alleged that by this contract the plaintiff sold to the defendant, and that defendant purchased from the plaintiff the stock therein mentioned for the sum of ten thousand dollars, of which five dollars were paid by the defendant on account of the purchase price at the time of the execution of the contract; that the defendant agreed to pay the balance of the purchase money in thirty days thereafter; that the thirty days expired, and the *10 defendant paid to the plaintiff five hundred dollars on the purchase price, and refused to pay the balance, although the plaintiff was willing and ready to perform his part of the contract. It is th'en alleged that, “after due notice to the defendant and after due advertisement thereof, the plaintiff sold said' two hundred shares of stock at public auction for the sum of nineteen hundred dollars.”

The defendant pleaded three pleas in confession and avoidance. . The first avers that, after the execution of the contract mentioned in the declaration, the. plaintiff rescinded the same; the second alleged that after the failure of the defendant to take and pay for the stock in the declaration mentioned, the plaintiff went through the form of selling same, and that in conducting said sale the plaintiff did not, in good faith, en-' deavórto obtain .for said stock the best price he could; and in the' third plea it is averred that the plaintiff did not sell the stock, mentioned in the declaration, for the best price which he could, by acting in good faith, and with reasonable diligence have obtained for the same. The plaintiff traversed these pleas, and issues were joined. The legal effect of the defendant’s three pleas was the confession, or admission upon the record of every fact alleged in the declaration. The distinct and only defense raised by the pleas were the rescission of the contract; bad faith in the conduct of the sale by the plaintiff; anid want of good faith and reasonable diligence in the sale of the stock in consequence whereof he did not sell the stock.for the best price he might have obtained.

In this connection in might be proper to notice some of the exceptions to the testimony. Where a witness testifies upon a controverted fact, it is always competent for the opposite party, in order to' affect his credibility and to enable the jury to determine the value and weight to be given his evidence, on cross-examination to show the bias, prejudice, bad feeling-, or hostility of the witness. Mr. Greenleaf in his t vol. on Evidence (7th ed.), sec. 446, says that: “The power of cross-examination has been justly said to be one of the principal, and it certainly is one of the most efficacious tests, which the *11 law has devised for the discovery of truth. By means of it the situation of the witness with respect to the parties, and to the subject of litigation, his interest, his motives, his inclination, and prejudices, his means of obtaining a correct and certain knowledge of the fact to which he bears testimony, the manner in which he has used those means, his power of discernment, memory and description are all fully' investigated and ascertained, and submitted to the consideration of the jury, before whom he has testified, and who have thus had an opportunity of observing his demeanor, and of determining the just weight and value of his testimony. It is not easy for a witness, who is subjected to this test, to impose on a Court, or jury; and however artful the fabrication or falsehood might be, it cannot embrace all the circumstances to which a cross-examination maybe extended.” This right to interrogate the witness on cross-examination as to the matters mentioned by Mr. Greenleaf has never been denied in this State, when the testimony of the witness upon any material point was disputed. It was recognized in the case of Blessing v. Hape, 8 Md. 31, and many other cases. In Wyeth v. Walzl, 43 Md. 432, it was held that it was competent to show that a witness who had testified in the case was prejudiced, or was on bad terms with the plaintiff, or had a difficulty with him, or a law suit, or any other condition of the witness, without going into unnecessary particulars, showing his interest, bias or inclination, to enable the jury upon a proper consideration of all such circumstances, to estimate the value of his testimony.

We do not mean to impair or lessen or restrict the authority of these cases. However proper and unobjectionable many of the interrogatories may be, considered as abstract questions, so far as they were designed to impeach the credit of the witness, they were manifestly inadmissible, in this case, because no attempt or offer was made to contradict any fact testified to by Henry S. Regester, and besides every fact necessary to make out a pilma facie case for the plaintiff had been admitted by the defendant’s pleas. In B. & O. R. R. *12 Co. v. State, use of Strunz, 79 Md. 347, it was said: “It has been almost universally held that neither the admission nor the exclusion of testimony, when it does not appear to have affected the result, or prejudiced the appellant, will be regarded as sufficient ground for reversal.”

It was admitted that the following advertisement of the sale of the stock appeared in the Baltimore “Sun” on July the 24th, 31st, and August the 3rd, 1903, viz.: “Auction sale of two hundred shares of the capital stock of the J. Regester Sons Company. The undersigned will sell by public auction, at our salesroom, No. 7 East Lexington street, on Monday, 3rd day of August, 1903, at noon, for account of whom it may concern, two hundred shares of the capital stock of the J. Regester Sons Company, each share of the par value of one hundred dollars. Terms cash. T. C. Ruddell, 202 North Calvert street, Charles H. Behn, Union Trust Building, attorneys. Pattison & Gahan, auctioneers.”

It is also admitted that the defendant saw the notice of sale, and talked with Mr. Ruddell about the same, and that he offered no instructions as to the mode or manner of selling-the stock, but sent Mr. Smith to the sale, who bought the stock for the company by his instructions. The plaintiff’s evidence tending to show that demand was made, after default, upon the defendant for the payment of the purchase price before the stock was advertised for sale; that at the time of this demand the stock was produced and tendered to the defendant; that the sale was regularly and fairly made, and that Mr. Ruddell, plaintiff’s attorney, was instructed by him “to conduct the auction sale in an honest manner, and to get all the money he could for the stock and that he, the plaintiff, tried to conduct the sale in good faith.”

There was no fact testified to by the defendant, or by any of his witnesses to .impeach the fairness, or regularity of the sale, or to show the slightest misconduct on the part of any one connected with the sale. The burden was upon the defendant to sustain his pleas by clear and satisfactory proof. Bad faith, misconduct, or negligence in the discharge of duty *13 is never presumed, but must be proved. The presumption is that the person charged with the performance of duty has discharged that duty honestly and faithfully. There were no facts, or circumstances in the case legally sufficient to sustain the defense set up by the defendant’s second and third pleas, and the jury would not in our opinion have been justified in finding for the defendant on those pleas from the mere fact that bad feeling existed between him and his brother of the. kind sought to be introduced in the testimony. Great latitude, it is true, is allowed upon cross-examination, and the course of the examination from the necessity of the case must be directed and controlled in a large measure by the good sense and sound discretion of the presiding Judge, and his rulings will not be disturbed, unless it appears that some injustice or injury has been done.

It follows from what we have said that the offers of testimony contained in the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, ten and a-half, eleventh, fifteenth, sixteenth, seventeenth, eighteenth, nineteenth and twentieth exceptions were properly refused. The twelfth and thirteenth exceptions relate to the refusal of the Court to permit the defendant to prove that at some indefinite time the defendant tried to get an option on the stock. This was wholly irrelevant to the issues, and was rightly excluded. The fourteenth exception relates to the exclusion of the deposition of the witness, Monroe. This testimony could only have been offered upon the theory that it tended to show that the contract had been rescinded. A valid contract having been made, and there being no allegation of fraud or misrepresentation it could not be rescinded or set aside except by the consent of both parties to it. Wheeler v. R. R. Co., 115 U. S. 34.

The objections to the twenty-first and twenty-second exceptions were properly sustained. It was not contended that there had been a mutual mistake in the execution of the contract, and besides the defendant had recognized it as a binding obligation by the payment of a large sum in part performance of the contract. For these, and other reasons, it was the duty

*14 of the Court to refuse to admit the testimony. There was no error in the ruling on the twenty-fifth, and twenty-sixth exceptions: In the first offer of testimony no definite fact was proposed to be proved. The question was too general, and left the witness at liberty to state his judgment as to the plaintiff’s conduct, and it is not pretended that anything the plaintiff may have' done prevented the defendant, or any one else from attending the sale, or purchasing the stock.

■ The last exception relates to the action of the Court upon the prayers. The plaintiff’s second prayer asserted a sound legal principle; and he was entitled to a verdict if the jury found the facts therein stated. ■ The doctrine upon which the instruction rests is abundantly supported by authority. Sands v. Taylor, 5 John. 395; 2 Parsons on Contracts, 483 and 4; Clews v. Jameson, 182 U. S. 496; Camp v. Hamlin, 55 Ga. 259; Brownlee v. Bolton, 44 Mich. 218, and other cases.

The plaintiff's third prayer was properly granted. It merely instructed the jury that if they found a verdict for the plaintiff they were at liberty to allow interest from August 4th, 1903, the day succeeding the sale, but as the jury did not allow interest the defendant has no ground to complain of the instruction.

The defendant’s first, second and third prayers were properly refused. There was no legally sufficient evidence of bad faith in the making of the sale,.and none that the contract had been rescinded. There was another fatal objection to both the first and second prayers • of the defendant. They submitted to the jury a question of law viz.: reasonable diligence. Ewalt V: Harding, 16 Md. 170; Boyer v. Turner, 3 H. & J. 287; Crawford v. Berry, 6 G. & J. 70.

In Ewalt v. Harding, supra, it is said “That whether due diligence has been observed is a question to be decided by the Court on facts to be found by the jury.”

The plaintiff’s second prayer, in our opinion, submitted the whole case fairly to the jury, and, we think in view of all the testimony, most favorably to the defendant.

Judgment affirmed, the appellant to pay the costs.