The offers of evidence, the rejection of which is the subject of the first three assignments of error, were offers to prove matters that took place before the signing of the writing on which the plaintiff sues. Nothing was shown to take them out of the general rule that all preliminary negotiations are merged and terminated by the execution of the written contract. The burden of showing ground for allowing exceptions to this rule was upon plaintiff and failing to do so his offers were properly excluded.

In regard to the payments to be made by plaintiff there is no room for dispute as to the law. The dates and amounts *209were fixed and the provision of the contract was express “ that if the said Charles Vito fails to make payments or any one of them herein as above agreed upon, he shall forfeit as liquidated damages'the amount of money already paid on account of this agreement and the contract shall be rescinded.” Time was thus made of the essence of the contract and being so, a failure to perform on the day agreed, ipso facto involved the stipulated forfeiture, without the necessity of any affirmative act of the vendor. The cases in regard to leases, cited by appellant, do not sustain any repugnant doctrine. In Wills v. Manufacturers’ Nat. Gas Co., 130 Pa. 222, Westmoreland, etc. Nat. Gas Co. v. DeWitt, 130 Pa. 235, and others down to English v. Yates, 205 Pa. 106, the leases contained a clause that they should become void on failure of the lessee to pay the agreed rent, and the gist of the decisions is that as this clause was for benefit of the lessor it was not self-operating against his will, but only at his option. That is the full extent of the principle declared in those cases. As was said by our late Brother Clark in Wills v. Gas Co., supra (p. 233), “ the Pennsylvania cases are all cases in which the forfeiture was set up by the lessor upon the default of the lessee ; in none of them did the lessee set up his own default as a cause of forfeiture. No case has been called to our attention, in this or any other state, in England or elsewhere, which recognizes the doctrine that a party may take advantage of his own wrong, or set up his own default to work a forfeiture of his own contract.” . And it was said in English v. Yates, supra, “ parties may contract that on a default the lease may become void at the option of either party, yet such intent in the agreement must be so plain as to be unavoidable in order to sustain such a construction.” In the present case the plaintiff, admitting his own default, claimed to recover on the ground that the defendant had not by some affirmative act asserted and enforced the forfeiture. The learned judge rightly held that it was not necessary for him to do so.

No doubt the grafitor or lessor may waive the forfeiture either expressly or by estoppel arising from acts tending to mislead the grantee or lull him into the belief that strict performance will not be exacted. The learned judge below so held but directed the verdict because there was no sufficient evidence to *210justify the submission of the question of waiver to the jury. In this view we concur.

Judgment affirmed.