J.C. SHAH, J.

(1) ON May 13, 193G, Arumugam Chettiar and his five sons Madlirayyan. Sivathanu, Subbayyan. Sankaran and Bhagavathy executed a deed of partition of the property belonging to their joint family. In the last paragraph of the deed it was provided that Madurayyan, Sivathanu, Subbayyan and Bhagavathy "shall offect alienations among themselves in respect of the property falling to their respective shares in case any alienations are to be effected . On 2/05/1959, Subbayyan transferred his share of the property to one Veeramany for Rs. 2,500.00. Madurayyan and Bhagavathy then filed a suit in the court of the Principal District Munsiff, Nagarcoil, against the purchaser Veeramany for a decree declaring that they had a "right of pre-emption" inrespect of the property sold by Subbayyan and to obtain possession of that property from Veeramany on payment of Rs. 2,500.00. To this suit Subbayyan Chettiar and his son Arumugam Chettiar were impleaded as partie. To this suit Sivathanu was not impleaded as a party. The Trial court dismissed the suit holding that the plaintiffs were estopped by reason of their conduct from claiming to purchase property pursuant to the covenant in t