
    * ANGUS McDONALD, JAMES S. BECKWITH and JOHN MORRIS, Respondents, v. THE MOUNTAIN LAKE WATER COMPANY, Appellant.
    Waiver of Performance. — A waiver of the performance of a written contract under seal, may be shown by parol; and this waiver excuses the performance.
    Contract, Parol Variation of. — A parol variation of a written agreement, after its execution, will be upheld on the ground, that no one will be allowed to take advantage of the non-performance of that which he prevented.
    Appeal from the Superior Court of the City of San Francisco.
    This was an action brought by the plaintiff, to recover from the defendant for work and labor done, under a written contract under seal, stipulating for payments as the work progressed. Under the contract, the sum of $75,000 was to be paid on the first day of October, for work to be done during the month of September; provided, work to that amount had been done during that period. The plaintiffs claimed to recover for the amount of work actually done, viz; $53,000, during the month of September under the contract, alleging that they had been prevented from doing more, by the interposition of the defendant; and because of the defendant’s inability to pay according to the terms of the contract.
    The defendant denied the allegations of the complaint.
    By consent of parties, the case was referred to Joseph P. Hoge, Esq., as sole referee, to find the facts and report a judgment.
    The referee reported the facts, fully sustaining the allegations of the complaint; and judgment was entered thereon, in favor of the plaintiffs, for the sum of $56,710, with costs.
    Defendant moved to set aside the report of the referee, and for a new trial, on the grounds, among others, that the referee admitted the plaintiffs to introduce parol proof, to vary, set aside and change the special contract under seal, set forth 
       in*the complaint; also, parol evidence of a parol agreement to modify, change and alter the special contract declared upon, etc.
    The Court refused to set aside the report of the referee, or to grant a new trial, whereupon the defendant appealed.
    
      George O. Bates, for Appellant.
    The plaintiffs seek to recover under the contract, not upon the common counts. Parol evidence cannot be given to alter or vary the written contract. (3 Blackf. 358; 3 Term B. 592; 12 East, 583; 7 Taunt. 596; 13 Wend. 75.) •
    
      Foote, Aldrich & Stewart, for Bespondents.
    The rule of evidence relied on has no application; the evidence objected to was admitted to show a waiver, (Beach v. Govillard, decided at this term; 3 Johns. 528; 9 Pick. 298.) Tender and refusal or waiver, are equivalent to performance. Penalty and forfeiture are not to be favored in law, or tolerated in equity. There is no error on the face of the report of the referee, and the Court cannot look beyond it. (2 Cal. 322.)
   Mr. Justice Heydeneeldt

delivered the opinion of the Court.

Mr. Oh. J. Murray concurred.

The action is for the payment which, by the terms of the written contract, was to be made in September, on account of the work done in September. It is objected to the recovery, that the stipulated amount of work for the month was greater than that performed, and, therefore, the averment of performance is not sustained by the contract. It is well shown, however, by the pleadings, and the special finding, that the quantity of work was diminished at the instance and request of the defendant. This must be regarded as a waiver, which excuses the performance. But if, as is contended by the plaintiffs in error, it is a parol variation of an agreement under seal, such variation will be upheld after its execution, because one will not be permitted to take advantage of the non-performance of that which he prevented. (Green v. Wells, 2 Cal. 584.)

Judgment affirmed.  