1. This appeal arises out of a suit for pre emption. The plaintiff is a 03 sharer. The defendant-vendee is a stranger. The plaintiff adduced in evidence the Wanb-ul-arz of 1880. That document contains a referenda to a right of pre-emption, and according to the ruling of this Courts a reference in a Wajrb-id-arz to pre-emptive rights must be taken primi facie, to be a reference to a custom of pre-emption rather than to an arrangement between the co-sharers. Both the Courts below have quoted from this Wajib ul-arz. It appears that the word 'sale' was omitted and the Court of first instance attached considerable importance to the omission of this word. We think the lower Appellate Court was right in holding that the omission of the word 'sale' was accidental. Consequently, the Wajib-ul-arz produced by the plaintiff was evidence of the existence of a custom of preemption. The plaintiff, however, produced two witnesses in support of his case. One of the witnesses, a co-sharer himself, stated upon cross-examination that he had never heard of the existence of the right of pre-emption. He had to admit upon cross examination that the plaintiff himself had been a stranger and had purchased from a co-sharer and that no person claimed the right of pre-emption. This was of recent date. We wish to point out that the the proper issue in cases in which the custom of pre-emption is alleged to exist is, 'Does the custom exist'? The finding on the issue does not depend solely on the construction of any of the words in any particular Wajib-id-arz. The Court ought to consider all the evidence adduced by the parties on both sides. The Wajib ul-arz, of course, if adduced in evidence, must be carefully considered as part of the evidence. In the present case, if the plaintiff upon whom the onus lies of proving the existence of the eastern, had in addition to the Wajib-ul-arz shown that the transfers which had taken place, or the majority of such-transfers had been to co-sharers and not to strangers, this would be good evidence upon which the Court could act. Cases in which the right of pre-emption had been successfully claimed would also be proper evidence to consider. It is not even necessary that the cases should have actually come into Court. On the other hand, if the defendant-vendee could show that there had been numerous instances of sales to strangers and as in the present case the fact that the plaintiff himself had been a stranger should be taken into consideration and might be a reason for holding that no custom existed, and that any prima facie Case established by the production of the Wajib-ul-arz has been rebutted. In the case of Ganga Singh v. Chedi Lal 33 A. 605 : 8 A.L.J. 996 : 12 Ind. Cas. 98 the Court laid down at some length the way in which Courts ought to approach the consideration of cases of pre-emption. It is always to be borne in mind that the onus lies upon the plaintiff, and that it is the duty of the plaintiff to adduce proper and sufficient evidence to enable the Court to come to a conclusion that the custom claimed by him is an existing custom. In the present case, we think that the Court of first instance attached altogether too much weight to what we consider to be an accidental omission of the word 'sale.' On the other hand, the lower Appellate Court seemed to think that the Wajib-ul-arz was conclusive and did not consider the rest of the evidence in the case, that is to say, the admission of the plaintiff's own witnesses and the fact that the plaintiff himself was a stranger up to a recent date. In other words, there has been no proper trial of the all important issue in the case. We accordingly set aside the decree of the Court below and remand the case to the lower Appellate Court with directions to re-admit the appeal upon its original number and proceed to hear and determine the same having regard to the remarks we have made. We think that the Court ought to hear any additional documentary evidence which the parties on either side may produce. Of course, if such documentary evidence are documents which cannot be given in evidence without formal proof, the Court will allow such witnesses to be called. Costs in this Court will abide the event.