Sale of Land with Partial Ownership at Time of Contract

A contract for the sale of a plot of land, where the seller had promised to convey the full property but only held ownership of a portion at the time of the promise, was deemed null because the inability to transfer full title constituted a failure of the essential object of the sale. The court held that the seller's subsequent acquisition of the remaining title before the final deed did not remedy the initial lack of full ownership at the moment the obligation to sell was undertaken, rendering the initial agreement void for lack of a determinable and valid object at its inception.