Opinion by
Rice, J..This was an action upon an executory contract of sale, which was as follows:
“ Philadelphia, Aug. 1, 1895.
“ Sold to Mess. Thos. Roberts & Co., Philada., Penna. For account of Germain Fruit Co., Los Angeles, Cal. One Car Cal. Prunes in Bags at 4|-c. per lb. F. O. B. Cal. Equal quantities Each Size 60’s 70’s 80’s 90’s Choice New Fruit undipped — first half Sept., Shipment — Cash S. D. on arrival & Ex. of goods.
“ J. M. Stattepeb, & Co.”
The prunes were shipped from California on September 17, and arrived in Philadelphia on or about October 1. The defendants examined the goods, and after some negotiations, to which we shall refer hereafter, refused to accept them, because, as they alleged, they were not such goods either as to quality *504or condition as the plaintiff was required under the contract to deliver. The plaintiff subsequently sold the goods to a third party, and brought this suit to recover as damages their loss on the resale.
Upon cross-examination of the defendant’s representative the plaintiff was permitted to draw out the fact that the defendants had bought the prunes of this third party, and paid for them at the rate of four and three fourths cents per pound, which, according to the testimony, was equivalent to three and five eighths cents on the Pacific coast. The court correctly instructed the jury that this fact was not conclusive of the question, whether the prunes were “ choice prunes such as the contract called for,” and gave the jury very good reasons why they should not regard the defendants as concluded by this action. But it by no means follows that it was error to permit the witness to be cross-examined upon the subject. He had testified in chief as to what was meant in the trade by the term “ choice new undipped fruit,” and had sworn, that, if prunes are unmerchantable through being mixed with stones, or dirt, or sticks or anything of that kind, they would not fulfil a contract for “ choice ” fruit; also that these prunes were unmerchantable because they were sandy and gritty. Thus it is seen, that the cross-examination related to a fact, — namely the unmerchantability of the goods— stated in the examination in chief, and the object was to draw out from the witness a fact within his knowledge — namely that the defendants actually bought them for a fair price — which had a natural tendency to show the inaccuracy of the statement made in the examination in chief.
The rule requiring testimony to be confined to the point in issue is less strictly enforced in the cross-examination of witnesses than in their examination in chief. When the sole object of the cross-examination is to ascertain the accuracy or credibility of a witness and is confined to matters to which he has testified in chief, there is no ground for reversal. For this purpose a witness may sometimes be cross-examined as to collateral facts although the cross-examiner may be bound by his answers, and will not be permitted to contradict them. In view of the fact that the witness was the defendant’s buyer and had asserted in his examination in chief that these prunes were not merchantable, the court committed no error in permitting *505him to be asked the question complained of in the first assignment of error.
We come, then, to the second branch of the defense, which was, that the stipulation as to the time of shipment was an essential term of the contract and that strict compliance therewith was a condition precedent. It appears that when the goods arrived in Philadelphia and. delivery there was tendered, the objection that they had not been shipped on or before September 15, was not even suggested. This defense was an after thought, or, as the defendants allege, an after discovery. The defendants’ sole objection was, that they were not such goods as the plaintiff undertook to furnish. This was the point of dispute. According to the uncontradicted testimony the defendants then proposed an arbitration; the plaintiffs accepted the proposition; arbitrators were chosen, and they inspected the goods and decided “ that the prunes were choice undipped prunes but a little gritty.” Notwithstanding this, the defendants persisted in their objection and definitely refused to accept the goods. After suit was brought they raised the objection now under consideration.
In the contracts of merchants, the time of shipment is a convenient means of fixing the probable time of arrival, with a view of providing funds to pay for the goods, or of fulfilling .contracts with third persons, and is ordinarily regarded as of the essence of the contract; especially if the property is subject to sudden, frequent or great fluctuations in value. When time is of the essence of the contract it is a condition precedent, and, in the absence of waiver, strict performance is required, before the party on whom it is incumbent can call on the other party to fulfil his promises to accept and pay for the goods. See Beach on Contracts, 1616, et seq.; Norrington v. Wright, 115 U. S. 188; Heller’s Estate, 6 Pa. Superior Ct. 246, and authorities there cited. If the words of the contract are equivocal and susceptible of two interpretations the subsequent acts of the parties may be resorted to to show how they understood their contract and the practical construction they put upon it. If, however, the contract — speaking still of mercantile contracts — expresses the time, and the words of the contract are unambiguous the general rule is, that the question is one of construction, and therefore one of law for the court and not of *506fact for the jury: 2 Benj. on Sales, §§ 884-887, 1024 (4th Am. ed.); Bowes v. Shand, L. R. 2 App. Cases, 455. Granting that the words of this contract are not ambiguous, and assuming for a moment that the defendants had, without more, simply refused-to accept the goods, they might argue with much force, that it was the duty of the court to declare as a matter of law that time was of the essence of the contract, and might complain that the submission to the jury of the question of the intention of the parties did them harm. But not only were they silent as to the objection they now urge, but they induced action on the part of the plaintiffs which, at least, involved delay, if not expense, pending the arbitration.
The performance of a condition precedent may be waived by a p'arty in whose favor it is stipulated, either expressly or by the implication resulting from his acts or conduct. “But if time be made of the essence of the contract that may be waived by the conduct of the purchaser; and if the timéis once allowed to pass and the parties go on negotiating for completion of the purchase then time is no longer of the essence of the contract:” Webb v. Hughes, L. R. 10 Eq. 281; Hipwell v. Knight, 1 Y. & C. 401. See also. McKay v. McKenna, 173 Pa. 582; Pollock on Contracts, *464. It is said there can be no waiver implied ■here because the defendants did not learn until after suit was brought that the goods had not been shipped until the 17th. But the plaintiff did not conceal the fact and a simple inquiry would have brought the information. If the arrival of the goods was later than they expected, and had reason to expect, the delay put them on inquiry as to the time of shipment. Their conduct had a natural tendency to show, that under their interpretation of the contract the trifling delay in shipment was immaterial — as the jury have found — or to lead the plaintiff to believe, and to act on the belief, that strict performance was waived.
In either view of the question it is now too late to set up their ignorance, for which no one is responsible but themselves, as an excuse. Having put their objections to accepting the goods upon the single ground that they were not such goods as to condition and quality as the contract called for, and having induced an arbitration upon the point in dispute, they were not in a position after suit brought to set up the present de*507fense. We think the undisputed facts of the case, taken in connection with the verdict of the jury upon the disputed facts, bring it within the just and equitable principle, that when a party to a contract or transaction induces another to act upon the reasonable belief that he will waive certain rights or terms he will be estopped to insist upon such rights or terms to the injury of one misled by his conduct: 7 Am. & Eng. Ency. of Law, 32; Waters v. Wolf, 2 Pa. Superior Ct. 200.
Judgment affirmed.