JUDGMENT

PUNCHHI., J.:- This appeal by certificate, poses an important question of law, as to whether, a court sale held in execution of a final decree, passed in a suit for recovery of mortgage money, can be upset under the provisions of Section 47 of the Code of Civil Procedure, on the displacement of the preliminary decree upon which such final decree was based.

2. The question of law emerges on the facts summarized as follows:

Raja Abhoy Narain Deb was the owner of premises No. 117-A, Rash Behari Avenue, statedly a fashionable quarter of Calcutta, built on an area approximating 1 Bigha 6 cottachs, with three storied building on it consisting of 32 spacious rooms and two out houses. On the demise of Raja Abhoy Narain Deb, the appellant herein, and the pro forma respondents, succeeded as heirs to the same on September 15, 1949. The appellant and his co-heirs mortgaged their two-third interest in the said property as security for a loan of Rs. 27000/- obtained from the mortgagor Smt. Prokashini Biswas, the predecessor-in interest of the plaintiffs-respondents. After her death some of the heirs and legal representatives of Smt. Biswas, on March 13, 196 1, filed a mortgage suit for the recovery of the mortgage money etc. in the Court of the 3rd Subordinate Judge at Alipore, being title Suit No. 17 of 1961, seeking enforcement and sale of the mortgaged property. To this suit the left out heir of Smt. Biswas, originally arrayed as a defendant, was transposed as a co-plaintiff. On July 25, 1962, the trial Court passed a preliminary decree in the sum of Rs. 27000/for the principal sum and a sum of Rs. 24570/- for interest on the said principal, totalling Rs. 51570/-, together with costs. The sum of Rs. 51570/ - was proportioned in as much as two-third was ordered as payable to the original plaintiffs and the remaining one third to the transposed co-plaintiff. The decree stipulated that the mortgagors were allowed to pay the decretal amount in 15 equal annual instalments, to be deposited by the 30th June of each year, in the afore-mentioned proportions of two-third and one third, to the credit of the respective mortgagee-plaintiffs; the first instalment being payable by August 31, 1962. The mortgagee plaintiffs were also allowed interest on the sums due from the date of institution of the suit till the date of realisation of the entire sum. It was further stipulated that in default of any one of the instalments, the mortgagee-plaintiffs were at liberty to apply for making the decree final and in the event of such application being made the mortgaged property, or a sufficient part thereof, shall be directed to be sold, and for such purpose all necessary steps were required to be taken by the plaintiffs-mortgagees. On December 18, 1962, the present pro forma respondent No. 8, Kumar Sudhendu Narain Deb, filed F.A. No. 902 of 1964 against the aforesaid preliminary decree in the Calcutta High Court praying as well for stay of execution of the decree, which prayer was ultimately declined. Some deposits, however, were made to feed the preliminary decree but since there was a failure to deposit in the terms thereof, a final decree was passed by the Court of the 3rd Subordinate Judge, Alipore on March 6, 1963, even though F.A. No. 902 of 1964, the appeal against the preliminary decree was pending in the High Court.

3. The group of the decree-holders representing two-third interest filed an execution petition for realisation of their own share under the decree which was followed by another execution petition of the remaining decree-holder representing one-third interest, seeking realisation of his one-third share of the decretal amount. Both the execution petitions contained identical prayers for sale of the mortgaged property. The execution petitions were consolidated and numbered as Execution Petitions 11 and 13 of 1963 respectively. On August 10, 1963, proclamation of sale was drawn, apparently in the presence of parties. The decree-holders su