JUDGMENT

SHARMA, J.:- Special leave is granted.

2. This appeal arises out of a suit filed by the respondent against her brother, the appellant, for specific performance of an alleged contract of sale dated 23-6-1965 in respect of a house. The property was under a mortgage and according to the plaintiff, case, the defendant had agreed to execute a deed of sale on the redemption of the mortgage by her, which she did in 1970. In spite of her repeated demands the defendant failed to respect the agreement which necessitated the institution of the suit.

3. The defendant-appellant, besides pleading limitation, denied the agreement as also the plaintiffs allegation that she had redeemed the mortgage.

4. The question of limitation was taken up by the trial Court as a preliminary issue and decided in favour of the plaintiff. The order has been confirmed by the High Court by the impugned judgment.

5. The plaintiff served a notice in July 1984 demanding specific performance before filing the suit. It has been contended on behalf of the appellant that since the alleged agreement is said to have been executed in June 1965, the suit is barred by limitation, and alternatively, even counting the period of limitation from the alleged redemption in 1970, the suit has been filed after more than 14 years, that is, long after the expiry of three years period prescribed under Article 54 of the Limitation Act. The High Court has rejected the argument holding that since the cause of action of the suit was dependent on the redemption of the mortgage and no period was fixed within which it was necessary for the respondent to have redeemed the mortgage, it cannot be said that a date was fixed within the meaning of the third column of Article 54, which reads thus.-

Description of suit Period of limitation Time from which period begins to run

"54. For specific performance three years The date fixed for the performance, or, if no such date is fixed, when the plaintiff has notice that performance is refused."

As the notice preceding the suit was admittedly served within three years, the defendants plea of limitation was rejected.

6. The relevant provisions in the alleged agreement of sale as quoted in the judgment, of the trial Court reads as follows :-

"This house is under mortgage with Jethmal Bastimal for Rs. 1000/-. When you will get this house, the description of which is given below, redeemed from M/s. Jeth Mal Bastimal and take the papers of the registry in your possession, on that day I will have the sale deed of the said house, written executed and registered in your favour."

(Emphasis supplied)

The question is whether a date was fixed for the performance of the agreement and in our view the answer is in the affirmative. It is true that a particular date from the calander was not mentioned in the document and the date was not ascertainable originally, but as soon as the plaintiff redeemed the mortgage, it became an ascertained date. If the plaintiff had, immeditely after the redemption, filed the suit, could it be thrown out on the ground that she was not entitled to the specific performance asked for? We do not think so. She would have been within her rights to assert that she had performed her part of the contract and was entitled to insist that her brother should complete his part. The agreement is a typical illustration of a contingent contract within the meaning of S. 31 of the Indian Contract Act, 1872 and became enforceable as soon as the event of redemption (by the plaintiff herself) happened. We agree with the view of the Madras High Court in R. Muniswami Goundar v. B. M. Shamanna Gounda, AIR 1950 Mad 820 expressed in slightly different circumstances. The doctrine of id certum est quod certum reddi potest is clearly applicable to the case before us which in the language of Herbert Broom (in his book dealing with legal maxims) is that certainty need not be ascertained at the time; for if, in the fluxion of time, a day will arrive which will make it ce